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Participle form of verbs
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Give me a quiz using these questions and answers Identify the underlined verbal. When my car broke down, I had to call the mechanic. Infinitive Gerund Participle Not a Verbal The thrilled parents watched their child graduate as valedictorian. Infinitive Gerund Participle Not a Verbal I love my mother’s cooking; it is simply divine. Infinitive Gerund Participle Not a Verbal It is important for her to practice every single day. Infinitive Gerund Participle Not a Verbal Sophia agreed to meet with me, but then she never showed up. Infinitive Gerund Participle Not a Verbal Identify the infinitive in the following sentence: The students will hopefully be able to ride the roller coaster at Six Flags this weekend. To ride At Six Flags This weekend Hopefully be able Identify the underlined Verbal Phrase in the sentences: Using the kite string as an electrical conductor, Franklin captured a bit of lightning. Gerund Phrase Participial Phrase Infinitive Phrase None of the Above The electricity captured during his experiment was safely stored in a Leyden jar. Gerund Phrase Participial Phrase Infinitive Phrase None of the Above I’d give anything to have that kite now. Gerund Phrase Participial Phrase Infinitive Phrase None of the Above Identify the form of verbal used in the sentences: Kristen’s dream was singing in the local musical. Infinitive Gerund Participle Not a Verbal My favorite Olympic competition is swimming. Infinitive Gerund Participle Not a Verbal The barking dog jumped over the fence after a squirrel. Infinitive Gerund Participle Not a Verbal The crying child rushed to his mother. Infinitive Gerund Participle Not a Verbal The Joker came up with a terrifying plan. Infinitive Gerund Participle Not a Verbal Doomsday was fighting Superman, Batman, and Wonder Woman. Infinitive Gerund Participle Not a VerbalAnalysis is a method of organizing, sorting, and scrutinizing data in such a way that a research question can be answered or meaningful inferences can be drawn. 4 2. Bibliography is a list of all the sources used in the process of researching. 3. Concept refers to a mental idea of a phenomenon. These are words or terms that symbolize some aspects of reality. e. g. love, pain. 4. Conclusion provides a summary of the research. 5. Data is an information that can be words or numbers. 6. Data Gathering Tools refer to the devices/ instruments used to collect data such as questionnaire or computer- assisted interviewing system. 7. Data Presentation involves the use of a variety of different graphical techniques. 8. Descriptive study is a research design that describes “what is”( e.g. a survey). 9. In-Text Citation is the brief form of the reference included in the body of one’s work. 10. Limitations are restrictions in a study that may decrease the credibility and generalizability of the research findings. 11. Literature review is a critical summary or research on a topic of interest, generally prepared to put a research problem in context or to identify gaps and weaknesses in prior studies so as to justify a new investigation. 12. Plagiarism is the unethical practice of using words or ideas of another author/researcher without proper acknowledgement. 13. Quantitative Research is the process of collecting and analyzing numerical data. 14. Questionnaire is a set of questions used to gather information in a survey. 15. Research Topic is a subject or issue that a researcher is interested in when conducting a research. 16. Respondents are those persons who have been invited to participate in a particular study and have actually taken part in the study. 17. Research Question is the question around which a researcher centers his/ her research. 18. Sample is a part or subset of population selected to participate in the research study. 19. Socio Demographic Profile includes age, sex, education, migration, background and ethnicity, religious affiliation, marital status, household, employment, and income. 20.Variables are attributes or characteristics that can have more than one value, such as height or weight. These are qualities or quantities, properties or characteristics of people, things, or situations that change or varyEarlier in 2019 there was a lot of femicide uh girls being killed by their boyfriends because they did one or two things there are also cultures of if there is violence in terms of a marital relationship that that is fine if there's a marital rape that that is fine so you find such situations being normalized and it being also a taboo to speak about those issues the 2030 agenda for sustainable development is grounded in respect for human rights and the power of people to change the world every individual on the planet has the right to health and well-being in all aspects of their sexuality their body and their reproductive choices ensuring these rights is integral to addressing poverty education violence against women and gender equality sexual and reproductive health rights are agreed in international law they were fought for by courageous women's rights activists and advocates across a broad range of professional fields and frontline experiences by movements of all ages levels and backgrounds they are still being fought for while progress has been made globally many barriers remain especially for those most marginalized excluded or discriminated against human rights are central to delivering the 17 sustainable development goals in the sustainable development agenda indeed each sdg target is simultaneously a metric and a claim for human rights the interplay between these political commitments and human rights obligations is particularly important when it comes to achieving sexual and reproductive health rights for decades human rights-based tactics have been used to drive progress in this episode of right to a better world experts share challenges they have faced and tactics they have used to address them the challenges they describe occur in settings all around the world the strategies used are ones that they have found to be successful in their own settings viewers are encouraged to learn from these experiences and consider how tactics could be adapted to their own context when sexual and reproductive health begins with equality the discussions decisions programs and policies which follow can build towards a future where every individual is not only born free but lives free and equal in dignity and rights without violence or discrimination the time to take action is now violence against women is any act that results in or is likely to result in physical sexual or psychological harm or suffering to women this includes threats of such acts coercion or arbitrary deprivation of liberty in public or private life it happens everywhere in every country in the home in communities at work and at school crises including health and humanitarian crises frequently contribute to higher rates of violence against women violence against women is directed at women because of their status as women the consequences are dire jeopardizing women's health including sexual and reproductive health and mental health hampering their ability to participate fully in society causing tremendous physical and psychological suffering for both women and their children the majority of women survivors of violence do not disclose or seek any type of services efforts to address violence against women must recognize the many different contexts in which it occurs and the many different forms it can take the majority of violence against women is committed by an intimate partner her current or previous boyfriend or husband globally around 30 of women have experienced physical and or sexual violence by an intimate partner in their lifetime this increases the risk of acquiring an sti or in some regions hiv by 1.5 fold when a woman is experiencing violence especially from her partner she's really unable to keep safe from hiv men have power to decide how when and where sex should be done and the woman is at risk of being infected because she cannot say no schools are another setting where violence against girls can take place assault and harassment during their commute bullying sexual harassment and mental or physical abuse on school property are all challenges across various country contexts this has a direct impact on girls access to inclusive quality education a target of sdg4 and an indirect impact on many of their other human rights young girls are taking advantage of at a very young age and they do not understand the choices and the avenues whereby they can exercise their rights when it comes to sexual productive health and rights and so you find a lot of dropouts and a lot of girls also going through a lot of traumatic experiences that would be avoided if they had guidance promoting a safe and secure working environment for all is a cornerstone of sdg 8. this includes a workplace free from sexual harassment and violence but for many women especially women migrant workers and others in precarious employment this is far from reality so we went to naivasha which is a flower farm and we've met the informal workers the casual liberals working for the flower farms when for example the sexual violence cases are reported companies don't take them very seriously a wide range of tactics have been used to prevent and address violence against women and girls and to recognize it as a fundamental violation of human rights prevention of intimate partner violence is possible when interventions are informed by evidence of what works we started out by describing the problem we've now moved to research on what works what are the kinds of interventions that are successful both for preventing the problem from happening in the first place and also from interventions to respond the respect women framework on preventing violence against women developed by the who un women ohchr and other international agencies promotes seven strategies which focus on relationship skills strengthening empowerment of women services for health justice police and social sector poverty reduction environments made safer including schools workplaces and public spaces child and adolescence abuse prevented and transformation of gender attitudes beliefs and norms this action-oriented framework can enable policy makers and health implementers to design plan implement monitor and evaluate interventions and programs to prevent violence against women we have come a long way for sure we still have some ways to go and we need to do more to stop this violence from happening in the first place this involves addressing the social norms that still prevail in many settings that make this form of violence acceptable women are not exposed to gender-based violence by accident all because of an inbuilt vulnerability violence against women is rooted in discriminatory social norms and power dynamics dismantling these underlying causes of violence against women and girls is at the heart of achieving gender equality and empowering all women and girls as set out in the targets and indicators of sdg 5 ensuring healthy lives in sdg3 and reducing inequalities in sdg 10. women and men are valued differently society has heap privileges on the men while the women are looked at as subordinate power is not only the problem but also the solution to preventing violence against women we are making it personal everyone connects with power every day people living with power or grappling with power they find themselves within this whole conversation if you're working to create gnome change there has to be change at all levels strategies to raise awareness in communities about violence against women and girls are critical as there is still a lot of stigma and shame which inhibits many women and girls from talking about it intervention is like a big complicated word sometimes it's just about talking about dialogue i mean the fact that we went into schools and just began a conversation with parents um bringing them together in the school along with the school personnel and then having the conversation start from there and we also sort of train providers within schools to appropriately refer children to health facilities for care what we found was that this dialogue began to spark other conversations in the community and i guess they just felt that oh it's actually okay to talk about this openly rather than pretend that nothing is going on sassa is a community mobilization approach to prevent violence against women and hiv and aids it is activist led it's not workshop heavy based it comes away from the traditional programming of organizations going to do things themselves instead they support activists who do the activities with their friends and neighbors health systems play a critical role in responding to violence wherever it occurs supporting health workers to respond appropriately to violence as well as ensuring their work environment enables them to provide safe effective and quality survivor centred care are important strategies for better addressing violence against women and girls um we came to learn not to ask direct questions not to give our opinion or our judgment on them and let her speak and once with that flow starts once that connection is established that doctor-patient relationship emotionally is established she will actually tell you the whole history legal frameworks to promote enforce and monitor equality and non-discrimination on the basis of sex are an important sdg 5 indicator but putting laws in place does not automatically make them effective there are existing protections for women in the workplace or for individuals in the workplace in relation to harassment but we know from our call for evidence that they are not actually addressing the problem the recommendations that we developed included government implementing a mandatory duty for employers to take preventative steps to address harassment in the workplace so what we would like to see is government implement a much stronger legislative duty it has taken decades of struggle by the women's rights movement to persuade the international community to view violence against women as a human rights concern and a sustainable development priority not a private matter governments have obligations to respect protect and fulfill the right to a life free of violence and to provide for sanctions when they fail when seeking accountability the priority consideration must always be the safety and well-being of survivors respecting their wishes and autonomy and supporting them to make informed choices about the type of justice they want context is vitally important there are many strategies to hold perpetrators accountable including strategic litigation and public campaigns when the teachers impregnate the girls that means the system has failed and okay what they do is they blacklist the teachers and they are always removed from the payroll but we think that is not enough the case that was quite interesting is where one of the judges she did find a ruling against the teacher service commission the commission that is responsible for hiring teachers asking them that they must take responsibility and they were ordered to pay compensation to the girls who had gotten pregnant while in school the justice police issue came about a few years back when a young girl was raped and the punishment for her being ripped was that harappa she was gang-ripped and therapists were told to slash grass feminist organizations and young women organizations came back to the police and the police commissioner to ask and request that the people who are found to be perpetrators should be punished according to our constitution and according to the laws of the land and those are very big campaigns to get better justice so consequently they were jailed but also it was a sign that the system the police system had to be checked in terms of when someone reports a case any case of violence what happens and how is it followed through the maria pedra is another example of litigation that became a political mobilizer so this was a case from the inter-american commission that really galvanized a change in public policy a huge change because it was a case that addressed gender-based violence intimate partner violence it called on responsibility of brazil also for not having prevented this kind of violence the reality of a case that says you have the right to not be bruised you have the right to be free of physical psychological violence it's powerful it can change women's lives investing in autonomous women's movements has been one of the most important drivers of changes in laws and policies to address violence against women over the past 40 years according to data from over 70 countries women organizing to advance women's status define the very concept of violence against women raised awareness of the issue and put it on national and global policy agendas often we thought that it takes generations or centuries to change working intensely with the communities we can actually see change coming violence against women and girls is a violation of fundamental human rights to life and to physical and psychological integrity not to be tortured or treated in an inhuman and degrading way to respect for private and family life and the right not to be discriminated against this understanding is more than theoretical human rights-based tactics can offer a practical route to addressing systemic challenges across all the circumstances where violence against women and girls occurs including but not limited to at the hands of their partners at school and in the workplace by using evidence-informed prevention strategies addressing power relations and social norms community mobilizing and dialogue supporting health systems and professionals putting in place strong legal frameworks accessing justice and ending impunity feminist organizing and mobilizing every individual can help to deliver the 2030 agenda for sustainable development building a world in which women and girls are free from all forms of violence and discrimination [Music] youHEALTH EDUCATION 3. SPECIFIC OBJECTIVES: Students should able to know about_______ 1. definition of health education 2. aims of health education 3. objectives of health education 4. principles of health education 5. scope of health education 6. planning of health education 7. steps in planning health education 8. levels of health education 9. doctors s responsibility 4. INTRODUCTION: Health education is a term frequently used by health care professional. its aims at individual and community health. Health education is the translation of what is known about health into desirable individual and community behaviour pattern by means of an education process. Definition: “A process aimed at encouraging people to want to be healthy , to know how to stay healthy, to do what they can individually and collectively to maintain health And seek help when needed”. OBJECTIVES - To inform people or disseminate scientific knowledge about prevention of disease and promotion of health - To motivate people to change their habits and lifestyle that are harmful to their health also motivate people to adopt habits and ways of living conducive to healthy living. - To guide the people who need help to adapt and maintain healthy practices and lifestyle by showing proper community resources. --- PRINCIPLES OF HEALTH EDUCATION - Credibility Of Message: It is the degree to which the message to be communicated is perceived as trustworthy by the receiver. - Creating interest among participants: It is a psychological principle that people are unlikely to listen to things that are not of their interest. If a health programme is based on the felt needs, people will participate in the programme willingly. - Motivating the participants: Motivation is like a petrol engine that drives the mental engine. It is the fundamental desire in every person to learn. Motivation is contagious; one motivated person may spread motivation throughout the group. 13. - Enhance comprehension of content: It means health education should be based on the level of understanding, education and literacy of people at whom the teaching is directed. Teaching should be within the mental capacity of the audience. - Ensure reinforcement: Repetition at intervals is necessary to promote learning. Without reinforcement and feedback, students can go back to the pre-awareness stage. - Encourage active participation: Health education should aim at encouraging people to work actively with health workers and others in identifying their own health problems and also in developing solutions. 14. - Learning by doing: Teaching is effective when individuals actively participate in health education. Learning becomes active and quicker if the individuals are made active physically as well as psychologically. - Known to unknown: The people in a community know something and the health educator enlarges this knowledge. If the health educator links new knowledge with the old knowledge, it can enhance learning. - Maintaining good human relations: Sharing of information, ideas and feelings happens most easily between people who have a good relationship. 15. - Setting an example: The health educators should set a good example in the topic they are dealing with as it fosters better understanding. - Regular feedback: Feedback is one of the key concepts of the system approach. The health educator can modify the elements of the system in light of the feedback from his audience. For effective communication, feedback is of paramount importance - Efficient leadership: Leaders are agents of change and they can be made use of in health education work. Psychologists have shown and established that we learn best from people we respect and regard. 16. The essential attributes of a leader are as follows - Understands the needs of the community. - Provides proper guidance. - Takes initiative. - Is receptive to the views and suggestions of people. - Identifies himself with the community. Is selfless, honest, impartial, considerate and sincere. - Is easily accessible to people. 17. SCOPE OF HEALTH EDUCATION 1. Nutrition 2. Hygiene 3. Family health 4. Disease prevention and cantrol 5. Psychological health 6. Prevention of accident 7. Use of health services 8. Human biology 19. - Nutrition: The aim of nutrition education is to guide people to choose optimum and balanced diets, remove prejudices and promote good dietary habits. nutrition education is a major intervention for the prevention of malnutrition, promotion of health and improving the quality of life. 20. - Hygiene: This has two aspects: personal and environmental. Personal: The aim of personal hygiene is to promote standards of personal cleanliness . Environmental: Has two aspects: Domestic and community. All environmental sanitation programmes should include health education 21. - Family health: The family is the first defence as well as the chief reliance for the well-being of its members. One of the main tasks of health education is to promote family self-reliance, especially regarding the family's responsibilities in child bearing, child rearing, self-care and in influencing their children to adopt a healthy lifestyle. 22. - Disease prevention and control: Drugs alone will not solve health problems. Without health education, a person may fall sick again and again from the same disease. Educating the people about the prevention and control of locally endemic diseases is the first of the eight essential activities in primary health care. 23. - Psychological health: Psychological health problem can occur everywhere. There is a tendency to an increase in the prevalence of psychological diseases when there is a change in society from agriculture to an industrial economy and when people move from the warm intimacy of a village. 24. - Prevention of accidents: Accidents are a feature of the complexity of modern life. Accidents can occur in home, road and place of work. The predominant factor in accidents is carelessness that can be tackled by health education. 25. - Use of health services: Many people, particularly in rural areas, do not know what health services are available and many more do not know. There is a communication gap between the public and state health administration in the form of feedback for further improvement of health services. One of the declared aims of health education is to inform people about the health services available in their community. 26. PLANNING FOR HEALTH EDUCATION planning: is the process of making thoughtful and systemic decision about what needs to be done , how it has to be done, by whom And with what sources. 27. Principles of planning health education 1) Focus on actual current needs and context of community: It is important that plans are made with the needs and context of the community in mind. Health education should try to understand what is currently happening in the community one works in. 2) Plan for basic needs and interest of the community: Consider the basic needs and interests of the community. If the local needs and interests are not kept under consideration, the plans may not be effective. 28. 3) Planning with actual beneficiaries of health education: Plan with the people involved in the implementation of an activity. If people are included in planning, they will be more likely to participate and the plan will be more likely to succeed. 4) Identify and use all relevant community resources: It is essential that the health educator identify all the relevant resources that are locally available which could be used for benefit of people receiving the health education. 29. 5) Follow principle of flexibility: Planning should be flexible, not rigid. One should be able to modify the plans when necessary. For example, you would have to change your priorities if a new problem needing an urgent response arose. 6) A realistic plan not hypothetical: The planned activity should be achievable and take into consideration the financial, personal resources available and time constraints. Planning must be realistic; do not plan unachievable activities. 30. Steps in planning health education Planning is a continuous process. It does not just happen at the start of project . Health education must be well planned to actually improve and promote individual, family and community health 31. - Needs assessment: Conducting needs assessment is the first and probably the most important step in any successful planning process. assessment is the process of identifying and understanding the health problems of the community and their possible causes. - Identify priorities: After identifying the needs and resources of the community, the next is to identify their priorities because each community may have several problems but the urgent have to be given top priority in health education. For example: goitre 32. - Set the goals and objectives: In planning the process of health education, setting goals and objectives is the third and most essential step because these goals and objectives serve as consciously thought baseline parameters to be achieved during health education. - Develop strategies: Prior to the implementation of the health education intervention one must plan, develop and evaluate the several alternative strategies to achieve the set goals and objectives of health education because each problem and target community is quite unique. 33. - Implementation: This is the core phase of the health education process which includes carrying out the planned strategies so that the set goals and objectives of health education may be achieved. - Monitor and evaluation: This is the final step of the planning process of health education where continuous monitoring as well as end evaluation is carried out to ensure the degree to which stated goals and objectives have been achieved. 34. LEVELS/APPROACH OF HEALTH EDUCATION 35. INDIVIDUAL LEVEL - Individual Approach: The health education must first create an atmosphere of friendship and allow the individual to talk as much as possible. In this individual teaching we can discuss, argue and persuade the individual to change his behaviour. But by this we can reach to a small population and who come in contact with us. Methods of individual health education 1) Home visit 2) Personal contact/ counselling 3) Personnel letters 36. 1) Home visit: A home visit is one of the best approaches for individual health education because it can become one of the best opportunities for health education with individuals and their families. Home visits are important to understand the real background of families, their living conditions and the environment in which they live. 37. 2) Personal contact/counseling : Personal contacts or counselling (one-to-one communication) is a helping process where one person explicitly and purposefully gives his or her time to assist people explore their situations and act on a solution. After this the counsellor needs to work together with the person to find solutions that are appropriate to their situation. 38. 3) personal letters: Personal letters may also be used for individual health education, where health educators may get an opportunity to dispatch letters or printed education material to the people in a target community. 39. GROUP LEVEL Group health education may be useful way to deliver health education massages in efficient manner. A well organized group permits sharing of experiences and skills so that people are able to learn from each other. 40. Methods of group discussion 1)Lecture method: (Chalk & Talk ) A lecture may be defined as carefully prepared oral presentation of facts organized thoughts and ideas by a qualified person. The group should not be more than 30 and talk should not exceed 15-20 minutes. By using suitable audiovisual aids. 2) Group discussion: A group is an aggregation of people interacting in a face to face situation. It is a very effective method of health communication. 41. 3) Demonstration: A demonstration is a carefully prepared presentation to show how to perform a skill. This procedure is carried out step by step before an audience. 4) Panel discussion: In a panel discussion 4-8 qualified persons talk about the topic. Sit and discuss a given topic in front of a large group/audience. The chairman opens the meeting. Panel comprises of a chair person and 4-8 speakers. After the main aspect of the subject are explored, the audience is invited to take part. 42. 5) Symposium: It is a series of speeches on a selected subject. Each expert person present it briefly and at the end of session the chair person make a comprehensive summary. Audience are allowed to raise question. 6) Workshops : It consists of series of meetings usually 4 or more with emphasis on an individual work, within the group and with the help of consultants and response personnel. 7) Role play: This is a brief acting out of an actual situation for the benefit of the audience for better understanding. 43. 8) Conference and seminars: This programmes are usually held on a regional, state/national level. Where several experts from different disciplines meet to deliberate on a particular theme, to appraise others of latest knowledge and research in a particular field. 9) Open forum: It refers to the public meeting which are held for various purposes in the community, for example: gram sabha 44. COMMUNITY LEVEL It is meant for a defined community and is not only to create awareness but also to help people understand their health problems and needs, find alternatives solutions to their problems and needs , implement them, evaluate and get feedback and accordingly do the needful. For health education at the community level, it is better to approach local leaders who are influential and who have the people’s confidence. These may include local officers such as gramsevak, panchayat sarpanch ,police officer or block development officer etc . 45. HOSPITAL LEVEL 1) Health Education in OPD/Outdoor: The patient and his attendants have to spend a lot of time in the outpatient department for health check-up, treatment, registration, diagnosis, admission procedure etc. This period can be utilised for health education. For this, the following means/devices can be used: - Exhibiting pictures, posters, charts, bulletin board and models in the waiting hall. - Arranging group discussion, slide show, or documentary film in a proper place and on a proper topic. - Giving health education on a personal level in the consulting room. This mainly includes nutrition clinic, family planning clinic, psychiatric clinic etc. 46. - Distributing pamphlets. - Arranging street plays or nukkad naatak in the outpatient department or its neighbourhood. 47. 2) Health Education in wards/ IPD: While taking care of the patients the indoor patients, doctors s have the opportunities to educate them. This period can be fully utilised to give health education to the patients. For this the following methods can be effective: - Conversation with the patient and motivating him for change in his behaviour. - Imparting health education by arranging live demonstration for nutrition, treatment, diagnosis etc. - Providing clinical or bedside teaching. - Providing incidental teaching to patient and his attendants. 48. - Presenting examples. To describe the gains of health education in an individual suffering from the same health education in an individual suffering from the same disease and arranging a meeting between the patient and the cured old patients.Owls, such as the young snowy owls on the previous page, have for centuries been symbols of both wisdom and mystery. To many cultures their piercing eyes have conveyed a look of intelligence. Their silent flight through darkened landscapes in search of prey has projected an air of power or wonder. For this chapter and this book, owls are an engaging example of a living organism from the world of biology—the study of life. BIOLOGY AND YOU Living in a small town, in the country, or at the edge of the suburbs, one may be lucky enough to hear an owl's hooting. This experience can lead to questions about where the bird lives, what it hunts, and how it finds its prey on dark, moonless nights. Biology, or the study of life, offers an organized and scientific framework for posing and answering such questions about the natural world. Biologists study questions about how living things work, how they interact with the environment, and how they change over time. Biologists study many different kinds of living things ranging from tiny organisms, such as bacteria, to very large organisms, such as elephants. Each day, biologists investigate subjects that affect you and the way you live. For example, biologists determine which foods are healthy. As shown in Figure 1-1, everyone is affected by this impor- tant topic. Biologists also study how much a person should exer- cise and how one can avoid getting sick. Biologists also study what CHARACTERISTICS OF LIFE The world is filled with familiar objects, such as tables, rocks, plants, pets, and automobiles. Which of these objects are living or were once living? What are the criteria for assigning something to the living world or the nonliving world? Biologists have established that living things share seven characteristics of life. These characteristics are organization and the presence of one or more cells, response to a stimulus (plural, stimuli), homeostasis, metabolism, growth and development, reproduction, and change through time. Organization and Cells Organization is the high degree of order within an organism’s internal and external parts and in its interactions with the living world. For example, compare an owl to a rock. The rock has a spe- cific shape, but that shape is usually irregular. Furthermore, differ- ent rocks, even rocks of the same type, are likely to have different shapes and sizes. In contrast, the owl is an amazingly organized individual, as shown in Figure 1-2. Owls of the same species have the same body parts arranged in nearly the same way and interact with the environment in the same way. Copyright © by Holt, Rinehart and Winston. All rights reserved. ORGANISM (Barn Owl) ORGAN (Owl’s Ear) TISSUE (Nervous Tissue Within the Ear) CELL (Nerve Cell) your air, land, and fAll living organisms, whether made up of one cell or many cells, have some degree of organization. A cell is the smallest unit that can perform all life’s processes. Some organisms, such as bacteria, are made up of one cell and are called unicellular (YOON-uh-SEL-yoo-luhr) organisms. Other organisms, such as humans or trees, are made up of multiple cells and are called multicellular (MUHL-ti-SEL-yoo-luhr) organisms. Complex multicellular organisms have the level of orga- nization shown in Figure 1-2. In the highest level, the organism is made up of organ systems, or groups of specialized parts that carry out a certain function in the organism. For example, an owl’s ner- vous system is made up of a brain, sense organs, nerve cells, and other parts that sense and respond to the owl’s surroundings. Organ systems are made up of organs. Organs are structures that carry out specialized jobs within an organ system. An owl’s ear is an organ that allows the owl to hear. All organs are made up of tissues. Tissues are groups of cells that have similar abilities and that allow the organ to function. For example, nervous tissue in the ear allows the ear to detect sound. Tissues are made up of cells. A cell must be covered by a membrane, contain all genetic information necessary for replication, and be able to carry out all cell functions. Within each cell are organelles. Organelles are tiny structures that carry out functions necessary for the cell to stay alive. Organelles contain biological molecules, the chemical compounds that provide physical structure and that bring about movement, energy use, and other cellular functions. All biological molecules are made up of atoms. Atoms are the simplest particle of an ele- ment that retains all the properties of a certain element. Response to Stimuli Another characteristic of life is that an organism can respond to a stimulus—a physical or chemical change in the internal or external environment. For example, an owl dilates its pupils to keep the level of light entering the eye constant. Organisms must be able to respond and react to changes in their environment to stay alive. ORGANELLE (Mitochondrion) BIOLOGICAL MOLECULE (Phospholipid) ATOM (Oxygen) cell from the Latin, cella meaning “small room,” or “hut” Word Roots and Origins www.scilinks.org Topic: Characteristics of Life Keyword: HM60257 mb06se_bios01.qxd 5/18/07 10:37 AM Page 7 8 CHAPTER 1 Homeostasis All living things, from single cells to entire organisms, have mecha- nisms that allow them to maintain stable internal conditions. Without these mechanisms, organisms can die. For example, a cell’s water content is closely controlled by the taking in or releas- ing of water. A cell that takes in too much water will rupture and die. A cell that doesn’t get enough water will also shrivel and die. Homeostasis (HOH-mee-OH-STAY-sis) is the maintenance of a stable level of internal conditions even though environmental conditions are constantly changing. Organisms have regulatory systems that maintain internal conditions, such as temperature, water content, and uptake of nutrients by the cell. In fact, multi- cellular organisms usually have more than one way of maintain- ing important aspects of their internal environment. For example, an owl’s temperature is maintained at about 40°C (104°F). To keep a constant temperature, an owl’s cells burn fuel to produce body heat. In addition, an owl’s feathers can fluff up in cold weather. In this way, they trap an insulating layer of air next to the bird’s body to maintain its body temperature. Metabolism Living organisms use energy to power all the life processes, such as repair, movement, and growth. This energy use depends on metabolism (muh-TAB-uh-LIZ-uhm). Metabolism is the sum of all the chemical reactions that take in and transform energy and materials from the environment. For example, plants, algae, and some bacteria use the sun’s energy to generate sugar molecules during a process called photosynthesis. Some organisms depend on obtaining food energy from other organisms. For instance, an owl’s metabolism allows the owl to extract and modify the chemi- cals trapped in its nightly prey and use them as energy to fuel activities and growth. Growth and Development All living things grow and increase in size. Some nonliving things, such as crystals or icicles, grow by accumulating more of the same material of which they are made. In contrast, the growth of living things results from the division and enlargement of cells. Cell division is the formation of two new cells from an existing cell, as shown in Figure 1-3. In unicellular organisms, the primary change that occurs following cell division is cell enlargement. In multi- cellular life, however, organisms mature through cell division, cell enlargement, and development. Development is the process by which an organism becomes a mature adult. Development involves cell division and cell differen- tiation, or specialization. As a result of development, an adult organism is composed of many cells specialized for different func- tions, such as carrying oxygen in the blood or hearing. In fact, the human body is composed of trillions of specialized cells, all of which originated from a single cell, the fertilized egg. This unicellular organism, Escherichia coli, inhabits the human intestines. E. coli reproduces by means of cell division, during which the original cell splits into two identical offspring cells. FIGURE 1-3 Observing Homeostasis Materials 500 mL beakers (3), wax pen, tap water, thermometer, ice, hot water, goldfish, small dip net, watch or clock with a second hand Procedure 1. Use a wax pen to label three 500 mL beakers as follows: 27°C (80°F), 20°C (68°F), 10°C (50°F). Put 250 mL of tap water in each beaker. Use hot water or ice to adjust the tem- perature of the water in each beaker to match the temperature on the label. 2. Put the goldfish in the beaker of 27°C water. Record the number of times the gills move in 1 minute. 3. Move the goldfish to the beaker of 20°C water. Repeat observations. Move the goldfish to the beaker of 10°C. Repeat observations. Analysis What happens to the rate at which gills move when the temp- erature changes? Why? How do gills help fish maintain homeostasis? Quick Lab mb06se_bios01.qxd 5/18/07 10:37 AM Page 8 THE SCIENCE OF LIFE 9 Reproduction All organisms produce new organisms like themselves in a process called reproduction. Reproduction, unlike other characteristics, is not essential to the survival of an individual organism. However, because no organism lives forever, reproduction is essential for the continuation of a species. Glass frogs, as shown in Figure 1-4, lay many eggs in their lifetime. However, only a few of the frogs’ off- spring reach adulthood and successfully reproduce. During reproduction, organisms transmit hereditary informa- tion to their offspring. Hereditary information is encoded in a large molecule called deoxyribonucleic acid, or DNA. A short segment of DNA that contains the instructions for a single trait of an organism is called a gene. DNA is like a large library. It contains all the books—genes—that the cell will ever need for making all the struc- tures and chemicals necessary for life. Hereditary information is transferred to offspring during two kinds of reproduction. In sexual reproduction, hereditary information recombines from two organisms of the same species. The resulting offspring are similar but not identical to their parents. For example, a male frog’s sperm can fertilize a female’s egg and form a single fer- tilized egg cell. The fertilized egg then develops into a new frog. In asexual reproduction, hereditary information from different organisms is not combined; thus the original organism and the new organism are genetically the same. A bacterium, for example, reproduces asexually when it splits into two identical cells. Change Through Time Although individual organisms experience many changes during their lifetime, their basic genetic characteristics do not change. However, populations of living organisms evolve or change through time. The ability of populations of organisms to change over time is important for survival in a changing world. This factor is also impor- tant in explaining the diversity of life-forms we see on Earth today. 1. How does biology affect a person’s daily life? 2. How does biology affect society? 3. Name the characteristics shared by living things. 4. Summarize the hierarchy of organization found in complex multicellular organisms. 5. What are the different functions of homeostasis and metabolism in living organisms? 6. How does the growth among living and nonliv- ing things differ? 7. Why is reproduction an important characteristic of life? CRITICAL THINKING 8. Applying Information Crystals of salt grow and are highly organized. Why don’t biologists con- sider them to be alive? 9. Analyzing Models When a scientist designs a space probe to detect life on a distant planet, what kinds of things should it measure? 10. Making Comparisons Both cells and organisms share the characteristics of life. How are cells and organismsood supply will be like in the near future.EVOLUTION OF LIFE Individual organisms change during their lifetime, but their basic genetic characteristics do not change. However, populations of liv- ing organisms do change through time, or evolve. Evolution, or descent with modification, is the process in which the inherited characteristics within populations change over generations, such that genetically distinct populations and new species can develop. Evolution as a theme in biology helps us understand how the various branches of the “tree of life” came into existence and have changed over time. It also explains how organisms alive today are related to those that lived in the past. Finally, it helps us understand the mechanisms that underlie the way organisms look and behave. Natural Selection The ability of populations of organisms to change over time is important for survival in a changing world. According to the theory of evolution by natural selection, organisms that have certain favorable traits are better able to survive and reproduce success- fully than organisms that lack these traits. One product of natural selection is the adaptation of organisms to their environment. Adaptations are traits that improve an indi- vidual’s ability to survive and reproduce. For example, rabbits with white fur and short ears in a snowy place, such as the one in Figure 1-7a, may avoid predators and frostbitten ears more often than those with dark fur and long ears. Thus, the next generation of rabbits will have a greater percentage of animals carrying the genes for white fur and short ears. In contrast, the brown, long- eared rabbit, as shown in Figure 1-7b, would survive and reproduce more successfully in a hot desert environment. The survival and reproductive success of organisms with favor- able traits cause a change in populations of organisms over gener- ations. This descent with modification is an important factor in explaining the diversity of organisms we see on Earth today. 1. Name three unifying themes found in biology. 2. How is the unity and diversity in the living world represented? 3. Identify the three domains and the kingdoms found in each domain. 4. How are organisms interdependent? 5. Describe why evolution is important in explain- ing the diversity of life. 6. Distinguish between evolution and natural selection. CRITICAL THINKING 7. Applying Information Assign the various top- pings you put on pizza to the appropriate domains and kingdoms of life. 8. Analyzing Graphics According to the “tree” in Figure 1-5, which of these pairs are more closely related: Archaea:Bacteria or Archaea:Eukarya? 9. Making Hypotheses Fossil evidence shows that bats descended from shrewlike organisms that could not fly. Write a hypothesis for how natural selection might have led to flying bats. SECTION 2 REVIEW (a) This short-eared arctic hare, Lepus arcticus, is hidden from predators and protected from frostbite in a snowy environment. (b) The mottled brown coats of desert rabbits blend in with the dirt and dry grasses, and their long ears help them radiate excess heat and thus avoid overheating. FIGURE 1-7 (a) (b) Copyright © by Holt, Rinehart and Winston. All rights reserved. THE SCIENCE OF LIFE 13 TH E STUDY OF BIOLOGY Curiosity leads us to ask questions about life. Science provides a way of answering such questions about the natural world. Science is a systematic method that involves forming and testing hypotheses. More importantly, science relies on evidence, not beliefs, for drawing conclusions. SCIENCE AS A PROCESS Science is characterized by an organized approach, called the scientific method, to learn how the natural world works. The methods of science are based on two important principles. The first principle is that events in the natural world have natural causes. For example, the ancient Greeks believed that lightning and thunder occurred because a supernatural god Zeus hurled thunderbolts from the heavens. By contrast, a scientist considers lightning and thunder to result from electric charges in the atmos- phere. When trying to solve a puzzle from nature, all scientists, such as the one in Figure 1-8, accept that there is a natural cause to solve that puzzle. A second principle of science is uniformity. Uniformity is the idea that the fundamental laws of nature operate the same way at all places and at all times. For example, scientists assume that the law of gravity works the same way on Mars as it does on Earth. Steps of the Scientific Method Although there is no single method for doing science, scientific studies involve a series of common steps. 1. The process of science begins with an observation. An observation is the act of perceiving a natural occurrence that causes someone to pose a question. 2. One tries to answer the question by forming hypotheses (singular, hypothesis). A hypothesis is a proposed explanation for the way a particular aspect of the natural world functions. 3. A prediction is a statement that forecasts what would happen in a test situation if the hypothesis were true. A prediction is recorded for each hypothesis. 4. An experiment is used to test a hypothesis and its predictions. 5. Once the experiment has been concluded, the data are analyzed and used to draw conclusions. 6. After the data have been analyzed, the data and conclusions are communicated to scientific peers and to the public. This way oth- ers can verify, reject, or modify the researcher’s conclusions. SECTION 3 OBJECTIVES ● Outline the main steps in the scientific method. ● Summarize how observations are used to form hypotheses. ● List the elements of a controlled experiment. ● Describe how scientists use data to draw conclusions. ● Compare a scientific hypothesis and a scientific theory. ● State how communication in science helps prevent dishonesty and bias. VOCABULARY scientific method observation hypothesis prediction experiment control group experimental group independent variable dependent variable theory peer review All researchers, such as the one releasing an owl above, use the scientific method to answer the questions they have about nature. FIGURE 1-8 Copyright © by Holt, Rinehart and Winston. All rights reserved. 14 CHAPTER 1 OBSERVING AND ASKING QUESTIONS The scientific method generally begins with an unexplained observa- tion about nature. For example, people have noticed for thousands of years that owls can catch prey in near total darkness. As shown in steps and of Figure 1-9, an observation may then raise ques- tions. The owl observation raises the question: How does an owl detect prey in the dark? FORMING A HYPOTHESIS After stating a question, a biologist lists possible answers to a sci- entific question—hypotheses. Good hypotheses answer a question and are testable in the natural world. For example, as shown in step Figure 1-9, there are several possible hypotheses for the question of how owls hunt at night: (a) owls hunt by keen vision in the dark; (b) owls hunt by superb hearing; or (c) owls hunt by detecting the prey’s body heat. Predicting To test a hypothesis, scientists make a prediction that logically fol- lows from the hypothesis. A prediction is what is expected to hap- pen if each hypothesis were true. For example, if hypothesis (a) is true, (owls hunt by keen night vision) then one can predict that the owl will pounce only on the mouse in either a light or a dark room. If hypothesis (b) is true (owls hunt by hearing), then one can pre- dict that in a lighted room, the owl will pounce closer to the mouse’s head. But, in a dark room, the owl should pounce closer to a rustling leaf attached to the mouse. Finally, if hypothesis (c) is true (owls hunt by sensing body heat), then an owl would strike only the prey no matter the room conditions, because owls hunt by detecting the prey’s body heat. 3 1 2 Copyright © by Holt, Rinehart and Winston. All rights reserved. A scientific study includes observations, questions, hypotheses, predictions, experiments, data analysis, and conclu- sions. A biologist can use the scientific method to set up an experiment to learn how an owl captures prey at night. FIGURE 1-9 1 OBSERVATION Owls capture prey on dark nights. 2 QUESTION How do owls detect prey on dark nights? 3 HYPOTHESES a) Owls hunt in the dark by vision. b) Owls hunt in the dark by hearing. c) Owls hunt in the dark by sensing body heat. THE SCIENCE OF LIFE 15 Notice that these predictions make it difficult to distinguish be- tween the vision and body heat hypotheses. The reason is that both hypotheses predict that the owl could grab the mouse in a dark room. Also, these three hypotheses do not eliminate all other factors that could influence how the owl finds its prey. However, testing predictions can allow one to begin rejecting hypotheses and thus to get closer to determining the answer(s) to a question. DESIGNING AN EXPERIMENT Biologists often test hypotheses by setting up an experiment. Step in Figure 1-9 outlines an experiment to test the hypotheses about how an owl hunts at night. First, experimenters set up a room with an owl perch high on one side and a small trap door on the other side for releasing mice. Then, they tied a leaf to each mouse’s tail with a string and released each mouse into the room. Next, each mouse ran silently across the room, but the leaf trailed behind, making a rustling noise. During half of the trials, the lights were on. During the other half, the room was dark. Technicians videotaped all the action in the chamber with an infrared light, which owls cannot see. The researchers then viewed the videos and measured the position of the owl’s strike relative to each mouse’s head. Performing the Experiment Many scientists use a controlled experiment to test their hypotheses. A controlled experiment compares an experimental group and a control group and only has one variable. The control group pro- vides a normal standard against which the biologist can compare results of the experimental group. The experimental group is iden- tical to the control group except for one factor, the independent variable. The experimenter manipulates the independent variable, sometimes called the manipulated variable. 4 4 EXPERIMENT 5 DATA COLLECTION AND ANALYSIS Measure and compare the distance from the owl’s strike to the mouse and to the leaf in light and dark. 6 CONCLUSION Data supported the hearing hypothesis: Owls hunt in the dark by hearing. prey Test predictions of the three hypotheses. Control: In the light Experimental: In the dark 1 2 3 4 5 6 7 8 9 10 11 Predicting Results Materials 2 Petri dishes with agar, cellophane tape, wax pen Procedure 1. Open one of the Petri dishes, and streak your finger across the surface of the agar. 2. Replace the lid, and seal it with the tape. Label this Petri dish with your name and a number 1. 3. Seal the second Petri dish with- out removing the lid. Label this Petri dish with your name and the number 2. 4. Write a prediction about what will happen in each dish. Store your dishes as your teacher directs. Record your observations. Follow your teacher’s directions for disposal of your dishes. Analysis Was your prediction accurate? What evidence can you cite to support your prediction? If you did not obtain the results you predicted, would you change your testing method or your prediction? Explain. Evaluate the importance of obtaining a result that does not support your prediction. Quick Lab mb06se_bios03.qxd 5/18/07 10:40 AM Page 15 16 CHAPTER 1 The independent variable in the owl experiment is the presence or absence of light. In the owl experiment, the control group hunts in the light, and the experimental group hunts in the dark. In addi- tion to varying the independent variable, a scientist observes or measures another factor called the dependent variable, or respond- ing variable, because it is affected by the independent variable. In the owl experiment, the dependent variable is distance from the owl’s strike to the mouse’s head. Testing the Experiment Some controlled experiments are conducted “blind.” In other words, the biologist who scores the results is unaware of whether a given subject is part of the experimental or control group. This factor helps eliminate experimenter bias. Experiments should also be repeated, because living systems are variable. Moreover, scien- tists must collect enough data to find meaningful results. COLLECTING AND ANALYZING DATA Most experiments measure a variable—the dependent variable. This measurement provides quantitative data, data measured in numbers. For example, in the experiment above, scientists mea- sured the distance of an owl’s strike from the prey’s head in cen- timeters, as shown in step of Figure 1-9. An event’s duration in milliseconds is also an example of quantitative data. Biologists usually score the results of an experiment by using one of their senses. They might see or hear the results of an experiment. Scientists also extend their senses with a micro- scope for tiny objects or a microphone for soft sounds. In the owl experiment, biologists extended their vision with infrared cameras. Analyzing and Comparing Data After collecting data from a field study or an experiment and then organizing it, biologists then analyze the data. In analyzing data, the goal is to determine whether the data are reliable, and whether they support or fail to support the predictions of the hypothesis. To do so, scientists may use statistics to help determine relation- ships between the variables involved. They can then compare their data with other data that were obtained in other similar studies. It is also important at this time to determine possible sources of error in the experiment just per- formed. Scientists usually display their data in tables or graphs when analyzing it. For the owl study, biologists could have made a bar graph such as the one in Figure 1-10, which shows the average distance from the owl’s strike relative to the mouse’s head or the leaf in the light and in the dark. 5 5 0 10 15 20 25 In the light In the dark Average distance from strike (cm) Distance Between Owl Strike and a Mouse or From a Leaf Attached to Mouse 30 Mouse Leaf Mouse Leaf The data below are hypothetical results that might occur from the described owl experiment.The independent variable is the darkness of the room, and the dependent variable is how far the owl struck from the mouse’s head.The data show that the owl strikes more accurately at the mouse in the light but strikes more accurately at the leaf in the dark. FIGURE 1-10 Copyright © by Holt, Rinehart and Winston. All rights reserved. THE SCIENCE OF LIFE 17 DRAWING CONCLUSIONS Biologists analyze their tables, graphs, and charts to draw conclu- sions about whether or not a hypothesis is supported, as shown in step of Figure 1-9. The hypothetical owl data show that in the light, owls struck with greater accuracy at the mouse than at the leaf, but in the dark, owls struck with greater accuracy at the leaf than the mouse. Thus, the findings support the hearing hypothe- sis, but not the vision hypothesis. An experiment can only disprove, not prove, a hypothesis. For example, one cannot conclude from the results that the hearing hypothesis is proven to be true. Perhaps the owl uses an unknown smell to strike at the mouse. One can only reject the vision hypothe- sis because it did not predict the results of the experiment correctly. Acceptance of a hypothesis is always tentative in science. The scientific community revises its understanding of phenomena, based on new data. Having ruled out one hypothesis, a biologist will devise more tests to try to rule out any remaining hypotheses. Making Inferences Scientists often draw inferences from data gathered during a field study or experiment. An inference (IN-fuhr-uhns) is a conclusion made on the basis of facts and previous knowledge rather than on direct observations. Unlike a hypothesis, an inference is not directly testable. In the owl study, it is inferred that the owl detects prey from a distance rather than by direct touch. Applying Results and Building Models As shown in Figure 1-11, scientists often apply their findings to solve practical problems. They also build models to represent or describe things. For example in 1953, James Watson and Francis Crick used cardboard balls and wire bars to build physical models of atoms in an attempt to understand the structure of DNA. Mathematical models are sets of equations that describe how dif- ferent measurable items interact in a system. The experimenter can adjust variables to better model the real-world data. CONSTRUCTING A THEORY When a set of related hypotheses is confirmed to be true many times, and it can explain a great amount of data, scientists often reclassify it as a theory. Some examples include the quantum the- ory, the cell theory, or the theory of evolution. People commonly use the word “theory” in a different way than scientists use the word. People may say “It’s just a theory” suggesting that an idea is untested, but scientists view a theory as a highly tested, generally accepted principle that explains a vast number of observations and experimental data. 6 Copyright © by Holt, Rinehart and Winston. All rights reserved. Biologists often apply their knowledge of the natural world to practical problems. Studies on the owl’s keen ability to locate sounds in space despite background noise are helping biotechnologists and bioengineers develop better solutions for people with impaired hearing, such as the people shown in this picture. FIGURE 1-11 18 CHAPTER 1 COMMUNICATING IDEAS An essential aspect of scientific research is scientists working together. Scientists often work together in research teams or sim- ply share research results with other scientists. This is done by publishing findings in scientific journals or presenting them at sci- entific meetings, as shown in Figure 1-12. Sharing information allows others working independently to verify findings or to con- tinue work on established results. For example, Roger Payne pub- lished the results of his owl experiments in a journal in 1971. Then, other biologists could repeat it for verification or use it to study the mechanisms introduced by the paper. With the growing impor- tance of science in solving societal issues, it is becoming increas- ingly vital for scientists to be able to communicate with the public at large. Publishing a Paper Scientists submit research papers to scientific journals for publica- tion. A typical research paper has four sections. First, the Introduction poses the problem and hypotheses to be investigated. Next, the Materials and Methods describe how researchers proceeded with the experiment. Third, the Results state the findings the experiment presented, and finally, the Discussion gives the significance of the experiment and future directions the scientists will take. Job Description Forensic biolo- gists are scientists who study biological materials to investigate potential crimes and other legal issues against humans and animals. Forensic scientists have knowledge in areas of biology, such as DNA and blood pattern analysis, and work in private sector and public laboratories. Focus On a Forensic Biologist As a law enforcement forensic specialist for the Texas Parks and Wildlife Department, Beverly Villarreal assists the game warden in investigations of fish and wildlife violations, such as illegal hunting and fishing. Villarreal analyzes blood and tissue samples to identify species of animals such as fish, birds, and reptiles. Her work helps game wardens as they enforce state laws regarding hunting and fishing. Most people think of forensic scientists as the glamorous crime investigators on TV, but according to Villarreal real forensic scientists “spend a great deal of time at a lab bench running analysis after analysis.” Many of the methods used in animal forensics, such as DNA sequenc- ing, are also used in human forensics. Education and Skills • High school—three years of science courses and four years of math courses. • College—bachelor of science in biol- ogy, including course work in zoology and genetics, plus experience in per- forming DNA analyses. • Skills—patience, attention to detail, and ability to use fine tools. Careers in BIOLOGY Forensic Biologist For more about careers, visit go.hrw.com and type in the keyword HM6 Careers. www.scilinks.org Topic: Scientific Investigations Keyword: HM61358 mb06se_bios03.qxd 5/18/07 10:40 AM Page 18 THE SCIENCE OF LIFE 19 1. What two principles make the scientific method a unique process? 2. Define the roles of observations and hypotheses in science. 3. Summarize the parts of a controlled experiment. 4. Summarize how we make conclusions about the results of an experiment. 5. Why is the phrase, “it’s just a theory” misleading? 6. Give another example of a conflict of interest. CRITICAL THINKING 7. Making Hypotheses On a nocturnal owl’s skull, one ear points up, and the other ear points down. Suggest a hypothesis for this observation. 8. Designing Experiments Design an experiment to establish if owls hunt by keen sight or hunt by heat seeking. 9. Calculating Information What was the average distance between the owl’s strike and the mouse if the recorded differences in this experiment were 25, 22, 19, 19, and 15? SECTION 3 REVIEW After scientists submit their papers to a scientific journal, the editors of that journal will send the paper out for peer review. In a peer review, scientists who are experts in the field anonymously read and critique that research paper. They determine if a paper pro- vides enough information so that the experiment can be duplicated and if the author used good experimental controls and reached an accurate conclusion. They also check if the paper is written clearly enough for broad understanding. Careful analysis of each other’s research by fellow scientists is essential to making scientific progress and preventing scientific dishonesty. HONESTY AND BIAS The scientific community depends on both honesty and good sci- ence. While designing new studies, experimenters must be very careful to prevent previous ideas and biases from tainting both the experimental process and the conclusions. Scientists have to keep in mind that they are always trying to disprove their favorite ideas. Scientists repeat experiments to verify previous findings. This allows for science to have a method for self-correction and it also keeps researchers honest and credible to their peers in the field. Conflict of Interest For most scientists, maintaining a good reputation for collecting and presenting valid data is more important than temporary prestige or income. So, scientists try to avoid any potential conflicts of interest. For example, a scientist who owns a biotechnology company and manufactures a drug would not be the best researcher to critically test that drug’s safety and effectiveness. To avoid this potential con- flict of interest, the scientist allows an unaffected party, such as a research group, to test the drug’s effectiveness. The threat of a potential scandal based on misleading data or conclusions is a pow- erful force in science that helps keep scientists honest and fair. Scientists present their experiments in various forms. The scientists above are presenting their work in the form of a poster at a scientific meeting. FIGURE 1-12 Copyright © by Holt, Rinehart and Winston. All rights reserved. The Internet can provide a wealth of scientific information for a report, but the information may not always be credible or accurate. You can use the methods above to check the accuracy and credibility of your sources. SCIENCE TECHNOLOGY SOCIETY SCIENCE ON THE INTERNET: A New Information Age I n the past, students research- ing a science topic would typ- ically begin their research by visiting a library to use printed reference materials, such as encyclopedias. Today, most stu- dents research topics by using a computer and searching for information on the Internet. The Internet can provide students with a wealth of infor- mation. But which Web sites have accurate information, and which Web sites do not? Checking Web Addresses Students should use the Web address, or URL, to establish the Web site’s credibility. Usually, the domain name can suggest who has published the Web site. Web sites can be pub- lished by governmental agen- cies (ends in “dot gov” or .gov), by educational institutions (ends in “dot edu” or .edu), by organizations (ends in “dot org” or .org), or by commercial businesses (ends in “dot com” or .com). Government Web sites are usually reliable. Examples of credible governmental Web sites are the National Institutes of Health (NIH) and the Food and Drug Administration (FDA). University and medical school sites are also reliable sources of information. Many organiza- tions that research and teach the public about specific diseases and conditions can also provide reliable information. Examples of such organizations are the American Cancer Society and the American Heart Association. Evaluating Web Sites The credibility of the author of the Web site should also be checked. Make sure the author is not trying to sell anything and is established in his or her field. For example, a health Web site’s author should be a med- ical professional. It is also important to check the date that the information was posted on the Web to ensure that the information is current. Also, the Web site should provide ref- erences from valid sources, such as scientific journals or govern- ment publications. Finally, the student should always double-check informa- tion between several reliable Web sites. If two or three reliable sites provide the same informa- tion, the student can feel confi- dent in using that information. Web Sites for Students The Internet Connect boxes in this textbook have all been reviewed by professionals at the National Science Teachers Association (NSTA). Students can trust that these sites are reliable sources for science- or health-related topics. REVIEW 1. Which types of Web addresses are the most reliable? 2. List four important features to evaluate when using a Web site for research. 3. Supporting Reasoned Opinions Why do you think a Web site that is advertising a product may not offer accurate information? REVIEW 20 www.scilinks.org Topic: Using the Internet Keyword: HM61589 mb06se_biosts.qxd 5/18/07 10:42 AM Page 20 TOOLS AND TECHNIQUES With proper equipment and good methods, biologists can see, manipulate, and understand the natural world in new ways. Microscopes are one of many useful tools used to unlock nature’s biological secrets. MICROSCOPES AS TOOLS Tools are objects used to improve the performance of a task. Microscopes are tools that extend human vision by making enlarged images of objects. Biologists use microscopes to study organisms, cells, cell parts, and molecules. Microscopes reveal details that otherwise might be difficult or impossible to see. Light Microscopes To see small organisms and cells, biologists typically use a light microscope, such as the one shown in Figure 1-13. A compound light microscope is a microscope that shines light through a spec- imen and has two lenses to magnify an image. To use this micro- scope, one first mounts the specimen to be viewed on a glass slide. The specimen must be thin enough for light to pass through it. For tiny pond organisms, such as the single-celled paramecium, light passing through the organism is not a problem. For thick objects, such as plant stems, biologists must cut thin slices for viewing. There are four major parts of a compound light microscope. For further description of the parts of a micro- scope, see the Appendix. 1. Eyepiece The eyepiece (ocular (AHK-yoo-luhr) lens) magnifies the image, usually 10 times. 2. Objective Lens Light passes through the specimen and then through the objective lens, which is located directly above the specimen. The objective lens enlarges the image of the specimen. Scientists sometimes use stains to make the image easier to see. 3. Stage The stage is a platform that supports a slide holding the specimen. The slide is placed over the opening in the stage of the microscope. 4. Light Source The light source is a light bulb that provides light for viewing the image. It can be either light reflected with a mirror or an incandescent light from a small lamp. SECTION 4 OBJECTIVES ● List the function of each of the major parts of a compound light microscope. ● Compare two kinds of electron microscopes. ● Describe the importance of having the SI system of measurement. ● State some examples of good laboratory practice. VOCABULARY compound light microscope eyepiece (ocular lens) objective lens stage light source magnification nosepiece resolution scanning electron microscope transmission electron microscope metric system base unit Compound light microscopes open the human eye to an interesting world including tiny pond organisms, healthy and diseased cells, and the functioning of cell parts. FIGURE 1-13 Objective lens Eyepiece (ocular lens) Stage Light THE SCIENCE OF LIFE 21 Copyright © by Holt, Rinehart and Winston. All rights reserved. 22 CHAPTER 1 Magnification and Resolution Microscopes vary in powers of magnification and resolution. Magnification is the increase of an object’s apparent size. Revolving the nosepiece, the structure that holds the set of objective lens, rotates these lenses into place above the specimen. In a typical com- pound light microscope, the most powerful objective lens produces an image up to 100 times (100) the specimen’s actual size. The degree of enlargement is called the power of magnification of the lens. The standard ocular lens magnifies a specimen 10 times (10). To compute the power of magnification of a microscope, the power of magnification of the strongest objective lens (in this case, 100) is multiplied by the power of magnification of the ocular lens (10). The result is a total power of magnification of 1000. Resolution (REZ-uh-LOO-shuhn) is the power to show details clearly in an image. The physical properties of light limit the ability of light microscopes to resolve images, as shown in Figure 1-14a. At pow- ers of magnification beyond about 2,000, the image of the speci- men becomes fuzzy. For this reason, scientists use other microscopes to view very small cellsFilipinos are known for some traditions which form part of our Culture. They are deeply set in our way of life. They form part of our Family living. 1. Saying “PO” and “OPO” – is a way of showing your respect to elders or superior as well as to strangers. Home Economics and Livelihood Education 7 Seibo College 71 If you have any questions, you can go to your learning facilitator, but if everything is clear to you, proceed to the next activities. 2. Close Family ties - Even though children are grown-up with their own family, still they participate in helping their parents through providing them financial support when necessary. 3. Hospitality - is a popular trait among Filipinos. Any guest arriving upon our home is well entertained. 4. Calling your elder brother “Kuya”, “Manong”, or “Diko”and elder sister “Ate”, “Ditse” is a sign of respectElectrostatics The section of CBSE Class 12 Physics electrostatic potential and capacitance notes mainly deals with the in-depth analysis of electromagnetic phenomena when they are not performing any movements. Additionally, it is divided into ten further sub-topics to study the companion processes of reaching the state. These are - 1. Electric charge In this section of Physics ch 2 Class 12 notes, you get to learn about the basic features of electric charge and its expression in Physics. Along with its basics, the sections help to understand the full potential of charge. Different aspects of Charge included in Class 12 Physics Chapter 2 notes are - Definition Type: Positive and Negative Charge Unit and dimensional formula Point Charge Properties of Charge Comparison of Charge and Mass Methods of Charging Electroscope 2. Coulomb's Law Force is created when charges of opposite signs attract each other, and they repulse if the signs are the same. Coulomb's law tries to define this phenomenon through a mathematical formula, explicitly mentioned in Physics Class 12 notes Chapter 2. Moreover, there is key information about the variation of the constant k and its effect on a medium. Coulomb's law's vector form and the principle of superimposition are also explained in ch 2 Physics Class 12 notes. (Image will be uploaded soon) 3. Electric Field As stated in Class 12 Physics Chapter 2 notes, every positively or negatively charged particle has their respective electric fields. It feels a force at the time of interaction which might be attraction or repulsion. As it arises from electric charge, it is crucial to know about its different parts like - Electric field intensity Relation between electric force and electric field Super imposition of electric field Point charge Continuous charge distributions Properties of Electric Field Lines Motion of Charged Particles in an Electric field Learning more about the electric field from electric potential and capacitance notes Class 12 helps a student to get a grasp of upcoming chapters. 4. Electric Potential Energy When energy helps a charge to move from an electric field, it is known as the Electric Potential Energy. This section of electrostatic chapter Class 12 notes requires a student to study the Electron volt (eV), and the potential energy that an n number of charges can hold. 5. Electric Potential This section of Class 12 Physics Chapter 2 notes focuses on in-depth learning of Electric Potential or Voltage. Basically, it defines the potential movement of energy. 6. Relation between Electric Field and Potential Apart from knowing more about the relationship between the two values, Physics Class 12 Chapter 2 notes also discuss equipotential surfaces. 7. Electric Dipole Essentially, 'Dipoles' are two opposite points of charge represented with q and –q, with their distance between each other being 2a. Electric Dipoles are crucial in your study of Physics Class 12 Chapter 2 notes to learn more about electric fields and their potential. Additionally, Class 12 Physics Chapter 2 notes focus on the influence of electric dipoles on a uniform electric field mainly through Force and Torque, Work, and Potential Energy. In the last part of Electrostatics, further focus is on using the formulas to their fullest potential. It includes subsections of Electric Field, Electric Potential Energy, Electric Potential, and Electric Dipole. In the notes for electrostatic potential and capacitance, you will find proper solutions accompanied by clear and crisp diagrams for better understanding. 8. Gauss's Law Apart from just discussing the Gauss's Law, in Physics Class 12 ch 2 notes there is a thorough explanation of its properties and applications. The Gauss' Law states that net electric flux passing through a hypothetical closed surface is equal to the net electric charge present within the same closed surface. Being a broad part of the whole chapter, you may need to spend a little more time on it. Moving forward, it starts discussing the properties of conductors in relation to Gauss's Law. The Class 12 Physics notes Chapter 2 perfectly defines the journey to Gauss' Law from Coulomb's Law. Here is the Gauss's Law present in the Class 12 Physics ch 2 notes, (image will be uploaded soon) 9. Capacitors There is a dedicated section about Capacitors in the Class 12 Physics Chapter 2 notes elucidating its functions and importance as storage of potential electric energy. After explaining the structure of a capacitor, it points out the different types, parallel plate, spherical and cylindrical. The section of Chapter 2 notes of Physics Class 12 is further divided into subheads like: Properties of an ideal battery Grouping of capacitors Simple circuits (Series and Parallel) Dielectric Van de Graaff generator Combination of drops Charge distribution method Wheatstone Bridge-based circuit Extended Wheatstone Bridge Infinite network of capacitors Redistribution of charge between two capacitors Vedantu prepares the Class 12 Physics Chapter 2 notes with help from subject matter experts. In the PDF, you get a comprehensive idea of the topic along with potential answers to the most asked questions. Furthermore, the detailed explanation on each section and subsections are written in a simple language allows a student to ace their exams with wholesome knowledge. These Physics Chapter 2 Class 12 notes are going to be one of the best supplementary study materials besides a student’s textbooks. Visit the Vedantu website or download the app to get your hands on all important notes! Important Questions A charge of 4 × 10–8C is uniformly distributed on the surface of a spherical conductor, having a radius of 15 cm. Determine the electric field just outside this sphere at a point that is 15 cm from the centre of this sphere. Determine the capacitance given that the distance between the two plates has been reduced by half and the parallel plate capacitor holds a capacitance of 20 pF (where 1pF = 10-12 F) having air between the two plates. What will be the total capacitance of a combination where three capacitors, each having a capacitance of 20 pF, are connected in series. A square having a side of 10 cm has a 500 µC charge at its centre. Determine the work done to move a charge of 10 µC between two points that are diagonally opposite each other on the square. At an equatorial point, what will be the electrostatic potential because of an electric dipole? Calculate the work done to move a test charge, q, through a length of 1 cm along the equatorial axis of an electric dipole? Polarisation A capacitor has its plates enclosed in a medium that can be filled by insulating substances. A net dipole moment is then induced by an electric field in the dielectric. This event causes the field in an opposite direction. Equipotential Surface An equipotential surface is a type of surface where the potential always has a constant value. If considered as a point charge, the concentric spheres that are centred at a particular area of this charge are basically equipotential surfaces. Advantages of Vedantu's Revision Notes: A Comprehensive Resource for Effective Learning There are several reasons why one may refer to Vedantu's revision notes for studying a subject like Electrostatic Potential and Capacitance. Here are some key points: Comprehensive Coverage: Vedantu's revision notes provide a comprehensive coverage of the entire topic, ensuring that all important concepts and subtopics are included. Concise and Organized: The notes are designed to be concise, focusing on the key points and core ideas. They are organized in a structured manner, making it easy for students to navigate and revise the content. Simplified Explanation: The revision notes offer simplified explanations of complex concepts, making them more accessible and easier to understand. This helps students grasp the material more effectively. Key Formulas and Equations: The notes highlight the key formulas and equations relevant to the topic, ensuring that students have a clear understanding of the mathematical aspects of Electrostatic Potential and Capacitance. Examples and Illustrations: Vedantu's revision notes often include examples and illustrations that help clarify concepts and provide practical applications, enabling students to better relate theory to real-world scenarios. Quick Recap: The revision notes serve as a quick recap of the important points, allowing students to review the material efficiently before exams or assessments. Exam-Oriented Approach: Vedantu's revision notes are designed with an exam-oriented approach, focusing on the topics and concepts that are frequently asked in examinations. This helps students prepare effectively and increase their chances of scoring well. Accessible Anytime: Vedantu's revision notes are easily accessible online, allowing students to study at their convenience and revise the material anytime, anywhere.Generate all of these 25 questions Part A: Each correct answer is worth 5. 1. The regular pentagon shown has a side length of 2 cm. The perimeter of the pentagon is (A) 2 cm (B) 4 cm (C) 6 cm (D) 8 cm (E) 10 cm 2 cm 2. The faces of a cube are labelled with 1, 2, 3, 4, 5, and 6 dots. Three of the faces are shown. What is the total number of dots on the other three faces? (A) 6 (B) 8 (C) 10 (D) 12 (E) 15 3. The equation that best represents \a number increased by _ve equals 15" is (A) n 5 = 15 (B) n _ 5 = 15 (C) n + 5 = 15 (D) n + 15 = 5 (E) n _ 5 = 15 4. The line graph shows the number of bobbleheads sold at a store each year. The sale of bobbleheads increased the most between (A) 2016 and 2017 (B) 2017 and 2018 (C) 2018 and 2019 (D) 2019 and 2020 (E) 2020 and 2021 Number of 2016 2017 2018 2019 2020 Year Sale of Bobbleheads 2021 Bobbleheads 20 40 60 80 5. Starting at 72, Aryana counts down by 11s: 72; 61; 50; : : : . What is the last number greater than 0 that Aryana will count? (A) 4 (B) 5 (C) 6 (D) 7 (E) 8 6. In the diagram, \ABC = 90_. The value of x is (A) 68 (B) 23 (C) 56 (D) 28 (E) 26 Day of the Week 44° x° A B C x° 7. Which of the following values is closest to zero? (A) 1 (B) 5 4 (C) 12 (D) 4 5 (E) 0:9 Grade 8 8. A jar contains 267 quarters. One quarter is worth $0.25. How many quarters must be added to the jar so that the total value of the quarters is $100.00? (A) 33 (B) 53 (C) 103 (D) 133 (E) 153 9. A package of 8 greeting cards comes with 10 envelopes. Kirra has 7 cards but no envelopes. What is the smallest number of packages that Kirra needs to buy to have more envelopes than cards? (A) 3 (B) 4 (C) 5 (D) 6 (E) 7 10. For the points in the diagram, which statement is true? (A) e > c (B) b < d (C) f > b (D) a < e (E) a > c y x (e, f ) (a, b) (c, d ) Part B: Each correct answer is worth 6. 11. The 26 letters of the English alphabet are listed in an in_nite, repeating loop: ABCDEFGHIJKLMNOPQRSTUVWXY ZABC : : : What is the 258th letter in this sequence? (A) V (B) W (C) X (D) Y (E) Z 12. A public holiday is always celebrated on the third Wednesday of a certain month. In that month, the holiday cannot occur on which of the following days? (A) 16th (B) 22nd (C) 18th (D) 19th (E) 21st 13. A circular spinner is divided into three sections. An arrow is attached to the centre of the spinner. The arrow is spun once. The probability that the arrow stops on the largest section is 50%. The probability it stops on the next largest section is 1 in 3. The probability it stops on the smallest section is (A) 1 4 (B) 2 5 (C) 1 6 (D) 2 7 (E) 3 10 14. A positive number is divisible by both 3 and 4. The tens digit is greater than the ones digit. How many positive two-digit numbers have this property? (A) 4 (B) 5 (C) 6 (D) 7 (E) 8 15. A rectangular pool measures 20 m by 8 m. There is a 1 m wide walkway around the outside of the pool, as shown by the shaded region. The area of the walkway is (A) 56 m2 (B) 60 m2 (C) 29 m2 (D) 52 m2 (E) 50 m2 20 m 8 m 1 m Grade 8 16. The results of asking 50 students if they participate in music or sports are shown in the Venn diagram. What percentage of the 50 students do not participate in music and do not participate in sports? (A) 0% (B) 80% (C) 20% (D) 70% (E) 40% Music Sports 15 5 20 17. There are 2 3 as many golf balls in Bin F as in Bin G. If there are a total of 150 golf balls, how many fewer golf balls are in Bin F than in Bin G? (A) 15 (B) 30 (C) 50 (D) 60 (E) 90 18. In the sequence shown, Figure 1 is formed using 7 squares. Each _gure after Figure 1 has 5 more squares than the previous _gure. What _gure has 2022 squares? (A) Figure 400 (B) Figure 402 (C) Figure 404 (D) Figure 406 (E) Figure 408 Figure 1 Figure 2 Figure 3 19. Mateo's 300 km trip from Edmonton to Calgary passed through Red Deer. Mateo started in Edmonton at 7 a.m. and drove until stopping for a 40 minute break in Red Deer. Mateo arrived in Calgary at 11 a.m. Not including the break, what was his average speed for the trip? (A) 83 km/h (B) 94 km/h (C) 90 km/h (D) 95 km/h (E) 64 km/h 20. Equilateral triangle ABC has sides of length 4. The midpoint of BC is D, and the midpoint of AD is E. The value of EC2 is (A) 7 (B) 6 (C) 6:25 (D) 8 (E) 10 Part C: Each correct answer is worth 8. 21. The positive factors of 6 are 1, 2, 3, and 6. There are two perfect squares less than 100 that have exactly _ve positive factors. What is the sum of these two perfect squares? (A) 177 (B) 80 (C) 145 (D) 52 (E) 97 22. In the list p; q; r; s; t; u; v, each letter represents a positive integer. The sum of the values of each group of three consecutive letters in the list is 35. If q + u = 15, then p + q + r + s + t + u + v is (A) 85 (B) 70 (C) 80 (D) 90 (E) 75 Grade 8 23. The net shown is folded to form a cube. An ant walks from face to face on the cube, visiting each face exactly once. For example, ABCFED and ABCEFD are two possible orders of faces the ant visits. If the ant starts at A, how many possible orders are there? (A) 24 (B) 48 (C) 32 (D) 30 (E) 40 A D B C E F 24. The number 385 is an example of a three-digit number for which one of the digits is the sum of the other two digits. How many numbers between 100 and 999 have this property? (A) 144 (B) 126 (C) 108 (D) 234 (E) 64 25. Student A, Student B, and Student C have been hired to help scientists develop a new avour of juice. There are 4200 samples to test. Each sample either contains blueberry or does not. Each student is asked to taste each sample and report whether or not they think it contains blueberry. Student A reports correctly on exactly 90% of the samples containing blueberry and reports correctly on exactly 88% of the samples that do not contain blueberry. The results for all three students are shown below. Student A Student B Student C Percentage correct on samples 90% 98% (2m)% containing blueberry Percentage correct on samples 88% 86% (4m)% not containing blueberry Student B reports 315 more samples as containing blueberry than Student A. For some positive integers m, the total number of samples that the three students report as containing blueberry is equal to a multiple of 5 between 8000 and 9000. The sum of all such values of m is (A) 45 (B) 36 (C) 24 (D) 27 (E) 29