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9.1 Open Note Questions
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Slave ___________ were the limitations or rules for slaves in antebellum America.
Which of the following was NOT a component of family life?
A strong sense of community developed as a result of moving people and breaking up families.
Family members were often threatened to be sold as punishment
Slaves were encouraged to "marry"
Slaves had marriage ceremonies
Slave ___________ were the limitations or rules for slaves in antebellum America.
Which of the following was NOT a component of family life?
Religion during this time for enslaved people began discussion of the 'promised land.'
Due to many resisting enslavement, owners and white people often...
Free African Americans were considered citizens of the U.S.
Which area was known for having several places where discrimination based on race did not exist?
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 cells1. SA node sends an impulse causing the atria to contract 2. Blood moves from the right atrium into the right ventricle past the tricuspid valve 3. Blood moves from the left atrium into the left ventricle past the mitral or bicuspid valve 4. Impulse pauses at AV node to allow for maximum blood to be squeezed into the ventricles 5. Impulse travels to the AV bundle (or bundle of His) and down the bundle branches 6. Impulse travels out Purkinje fibers causing the apex to contract 7. The apex contraction increases the blood pressure in the ventricles causing the Mitral and Tricuspid (AV) valves to close. 8. Atria repolarize and begin to fill 9. Purkinje fibers cause the ventricle walls and papillary muscles to depolarize (contract) 10. Papillary muscles hold the AV valves shut (keep them from prolapsing) through the chordae tendineae connection 11. The aortic and pulmonary semilunar valves open when the pressure is higher in the ventricles than in the major arteries 12. Blood moves from right ventricle to pulmonary trunk/arteries past the pulmonary semilunar valve 13. Blood moves from left ventricle to aorta past the aortic semilunar valve 14. Blood pathway is arteries to arterioles, to capillaries (or capillary bed), to venules, veins and vena cava back to the right atrium 15. The ventricles start to repolarize (relax) which decreases the pressure in the ventricles 16. When the pressure is lower in the ventricles than in the major arteries, blood moves back toward heart shutting semilunar valves 17. When the aortic valve closes, the openings to the coronary arteries are exposed 18. Back pressure in the aorta pushes blood out the left and right coronary arteries supplying the heart with oxygenated blood 19. The AV valves open and blood moves from the atria into the ventricles when the ventricular pressure falls below atrial pressure. 20. The process starts again when the SA node fires causing the atria to contract.1. Flammable materials, like alcohol, should never be dispensed or used near A. an open door. B. an open flame. C. another student. D. a sink. 2. If a laboratory fire erupts, immediately A. notify your instructor. B. run for the fire extinguisher. C. throw water on the fire. D. open the windows. 3. Approved eye protection devices (such as goggles) are worn in the laboratory A. to avoid eye strain. B. to improve your vision. C. only if you don’t have corrective glasses. D. any time chemicals, heat or glassware are used. 4. If you wear contact lenses in the school laboratory, A. take them out before starting the lab. B. you do not have to wear protective goggles. C. advise your science instructor that you wear contact lenses. D. keep the information to yourself. 5. If you do not understand a direction or part of a lab procedure, you should A. figure it out as you do the lab. B. try several methods until something works. C. ask the instructor before proceeding. D. skip it and go on to the next part. 6. After completing an experiment, all chemical wastes should be A. left at your lab station for the next class. B. disposed of according to your instructor’s directions. C. dumped in the sink. D. taken home. 7. If a lab experiment is not completed, you should A. discuss the issue with your instructor. B. sneak in after school and work alone. C. come in during lunch and finish while eating lunch. D. make up some results. 8. You are heating a substance in a test tube. Always point the open end of the tube A. toward yourself. B. toward your lab partner. C. toward another classmate. D. away from all people. Science Laboratory Safety teSt 9. You are heating a piece of glass and now want to pick it up. You should A. use a rag or paper towels. B. pick up the end that looks cooler. C. use tongs. D. pour cold water on it. 10. You have been injured in the laboratory (cut, burn, etc.). First you should A. visit the school nurse after class. B. see a doctor after school. C. tell the science instructor at once. D. apply first aid yourself. 11. When gathering glassware and equipment for an experiment, you should A. read all directions carefully to know what equipment is necessary. B. examine all glassware to check for chips or cracks. C. clean any glassware that appears dirty. D. All of the above. 12. You want to place a piece of glass tubing into a rubber stopper after the tubing has been fire polished and cooled. This is best done by A. lubricating the tubing with water or glycerin. B. using a towel or cotton gloves for protection. C. twisting the tubing and stopper carefully. D. all of the above. 13. Personal eyeglasses provide as much protection as A. a face shield. B. safety glasses. C. splashproof chemical goggles. D. none of the above. 14. Long hair in the laboratory must be A. cut short. B. held away from the experiment with one hand. C. always neatly groomed. D. tied back or kept entirely out of the way with a hair band, hairpins, or other confining device. 15. In a laboratory, the following should not be worn. A. loose clothing. B. dangling jewelry. C. sandals. D. all of the above. 16. The following footwear is best in the laboratory. A. sandals B. open-toed shoes C. closed-toed shoes D. shoes appropriate for the weather3 © 2017 Flinn Scientific, Inc. All Rights Reserved. 17. Horseplay or practical jokes in the laboratory are A. always against the rules. B. okay. C. not dangerous. D. okay if you are working alone. 18. If a piece of equipment is not working properly, stop, turn it off, and tell A. the custodian. B. your lab partner. C. your best friend in the class. D. the science instructor. 19. If an acid is splashed on your skin, wash at once with A. soap. B. oil. C. weak base. D. plenty of water. 20. When you finish working with chemicals, biological specimens, and other lab substances, always A. treat your hands with skin lotion. B. wash your hands thoroughly with soap and water. C. wipe your hands on a towel. D. wipe your hands on your clothes. True—False T F 22. ■ ■ Hot glass looks the same as cold glass. 23. ■ ■ All chemicals in the lab are to be considered dangerous. 24. ■ ■ Return all unused chemicals to their original containers. 25. ■ ■ Work areas should be kept clean and tidy. 26. ■ ■ Pipets are used to measure and dispense small amounts of liquids. You should draw the liquid into the pipet using your mouth. 27. ■ ■ Laboratory work can be started immediately upon entering the laboratory even if the instructor is not yet present. 28. ■ ■ Never remove chemicals or other equipment from the laboratory. T F 29. ■ ■ Chipped or cracked glassware is okay to use. 30. ■ ■ Read all procedures thoroughly before entering the laboratory. 31. ■ ■ All unauthorized experiments are prohibited. 32. ■ ■ You are allowed to enter the chemical preparation/storage area any time you need to get an item. 33. ■ ■ Laboratory aprons should be worn during all lab activities. 34. ■ ■ It’s okay to pick up broken glass with your bare hands as long as the glass is placed in the trash. 35. ■ ■ Never leave a lit burner unattended. 21. Draw a diagram of your science room and label the locations of the following: ■ Fire Blanket ■ Fire Extinguisher(s) ■ Exits ■ Eyewash Station ■ Emergency Shower ■ Closest Fire Alarm Station ■ Waste Disposal Container(s)4 © 2017 Flinn Scientific, Inc. All Rights Reserved. Name: ________________________________________________ Date: ______________________________________________ 1. Flammable materials, like alcohol, should never be dispensed or used near A. an open door. B. an open flame. C. another student. D. a sink. 2. If a laboratory fire erupts, immediately A. notify your instructor. B. run for the fire extinguisher. C. throw water on the fire. D. open the windows. 3. Approved eye protection devices (such as goggles) are worn in the laboratory A. to avoid eye strain. B. to improve your vision. C. only if you don’t have corrective glasses. D. any time chemicals, heat or glassware are used. 4. If you wear contact lenses in the school laboratory, A. take them out before starting the lab. B. you do not have to wear protective goggles. C. advise your science instructor that you wear contact lenses. D. keep the information to yourself. 5. If you do not understand a direction or part of a lab procedure, you should A. figure it out as you do the lab. B. try several methods until something works. C. ask the instructor before proceeding. D. skip it and go on to the next part. 6. After completing an experiment, all chemical wastes should be A. left at your lab station for the next class. B. disposed of according to your instructor’s directions. C. dumped in the sink. D. taken home. 7. If a lab experiment is not completed, you should A. discuss the issue with your instructor. B. sneak in after school and work alone. C. come in during lunch and finish while eating lunch. D. make up some results. 8. You are heating a substance in a test tube. Always point the open end of the tube A. toward yourself. B. toward your lab partner. C. toward another classmate. D. away from all people. Science Laboratory Safety teSt 9. You are heating a piece of glass and now want to pick it up. You should A. use a rag or paper towels. B. pick up the end that looks cooler. C. use tongs. D. pour cold water on it. 10. You have been injured in the laboratory (cut, burn, etc.). First you should A. visit the school nurse after class. B. see a doctor after school. C. tell the science instructor at once. D. apply first aid yourself. 11. When gathering glassware and equipment for an experiment, you should A. read all directions carefully to know what equipment is necessary. B. examine all glassware to check for chips or cracks. C. clean any glassware that appears dirty. D. All of the above. 12. You want to place a piece of glass tubing into a rubber stopper after the tubing has been fire polished and cooled. This is best done by A. lubricating the tubing with water or glycerin. B. using a towel or cotton gloves for protection. C. twisting the tubing and stopper carefully. D. all of the above. 13. Personal eyeglasses provide as much protection as A. a face shield. B. safety glasses. C. splashproof chemical goggles. D. none of the above. 14. Long hair in the laboratory must be A. cut short. B. held away from the experiment with one hand. C. always neatly groomed. D. tied back or kept entirely out of the way with a hair band, hairpins, or other confining device. 15. In a laboratory, the following should not be worn. A. loose clothing. B. dangling jewelry. C. sandals. D. all of the above. 16. The following footwear is best in the laboratory. A. sandals B. open-toed shoes C. closed-toed shoes D. shoes appropriate for the weather5 © 2017 Flinn Scientific, Inc. All Rights Reserved. 17. Horseplay or practical jokes in the laboratory are A. always against the rules. B. okay. C. not dangerous. D. okay if you are working alone. 18. If a piece of equipment is not working properly, stop, turn it off, and tell A. the custodian. B. your lab partner. C. your best friend in the class. D. the science instructor. 19. If an acid is splashed on your skin, wash at once with A. soap. B. oil. C. weak base. D. plenty of water. 20. When you finish working with chemicals, biological specimens, and other lab substances, always A. treat your hands with skin lotion. B. wash your hands thoroughly with soap and water. C. wipe your hands on a towel. D. wipe your hands on your clothes. 21. Draw a diagram of your science room and label the locations of the following: ■ Fire Blanket ■ Fire Extinguisher(s) ■ Exits ■ Eyewash Station ■ Emergency Shower ■ Closest Fire Alarm Station ■ Waste Disposal Container(s) True—False T F 22. ■ ■ Hot glass looks the same as cold glass. 23. ■ ■ All chemicals in the lab are to be considered dangerous. 24. ■ ■ Return all unused chemicals to their original containers. 25. ■ ■ Work areas should be kept clean and tidy. 26. ■ ■ Pipets are used to measure and dispense small amounts of liquids. You should draw the liquid into the pipet using your mouth. 27. ■ ■ Laboratory work can be started immediately upon entering the laboratory even if the instructor is not yet present. 28. ■ ■ Never remove chemicals or other equipment from the laboratory. T F 29. ■ ■ Chipped or cracked glassware is okay to use. 30. ■ ■ Read all procedures thoroughly before entering the laboratory. 31. ■ ■ All unauthorized experiments are prohibited. 32. ■ ■ You are allowed to enter the chemical preparation/storage area any time you need to get an item. 33. ■ ■ Laboratory aprons should be worn during all lab activities. 34. ■ ■ It’s okay to pick up broken glass with your bare hands as long as the glass is placed in the trash. 35. ■ ■ Never leave a lit burner unattended. 1. Imperialism – 2. Alfred Mahan – 3. Sanford B. Dole – 4. Yellow Journalism – 5. U.S.S. Maine – 6. George Dewey – 7. Rough Riders – 8. Protectorate – 9. Foraker Act – 10. William Randolph Hearst – 11. Emilio Aguinaldo – 12. Open Door Notes (policy) – 13. Boxer Rebellion – 14. Panama Canal – 15. Roosevelt Corollary - 16. San Juan Hill - Question 1 Category: Current Events Question: What was the primary demand of the Kenyan Gen Z protesters featured in the BBC documentary Unmasked: The Truth Behind the Gen Z Protests? Options: A) Free education B) Repeal of the Finance Bill 2024 C) Climate change action D) New elections Correct Answer: B) Repeal of the Finance Bill 2024 Explanation: The BBC documentary highlights that Kenyan youth protested to demand the repeal of the Finance Bill 2024, which proposed tax hikes raising $2.7 billion. Question 2 Category: Science Question: Which gas, discovered on the sun before Earth, is the second most abundant element in the universe? Options: A) Hydrogen B) Oxygen C) Helium D) Nitrogen Correct Answer: C) Helium Explanation: Helium was first detected in the sun’s spectrum in 1868 and is the second most abundant element after hydrogen in the universe. Question 3 Category: Current Events Question: Which Kenyan city was the epicenter of the Gen Z protests covered in the BBC documentary Unmasked: The Truth Behind the Gen Z Protests? Options: A) Mombasa B) Nairobi C) Kisumu D) Eldoret Correct Answer: B) Nairobi Explanation: Nairobi, Kenya’s capital, was the main hub for the #OccupyParliament protests, with significant events like the Parliament breach occurring there, as shown in the documentary. Question 4 Category: History Question: Which empire, known for its vast trade networks, was centered in modern-day Turkey and lasted until the early 20th century? Options: A) Roman Empire B) Ottoman Empire C) Mongol Empire D) Byzantine Empire Correct Answer: B) Ottoman Empire Explanation: The Ottoman Empire, spanning over 600 years until 1922, was a major trade and cultural power centered in modern-day Turkey. Question 5 Category: Current Events Question: According to the BBC documentary, what technology helped document evidence of police brutality during the Kenyan Gen Z protests? Options: A) Drones B) Smartphone videos C) Facial recognition software D) Satellite tracking Correct Answer: B) Smartphone videos Explanation: The documentary used smartphone videos from protesters and bystanders, analyzed via open-source data, to document police brutality during the 2024 protests. Question 6 Category: Geography Question: What is the smallest country in the world by land area? Options: A) Monaco B) Vatican City C) San Marino D) Liechtenstein Correct Answer: B) Vatican City Explanation: Vatican City, with an area of about 44 hectares, is the smallest sovereign state in the world by land area. Question 7 Category: Current Events Question: What hashtag became synonymous with the Kenyan Gen Z protests, as featured in the BBC documentary Unmasked: The Truth Behind the Gen Z Protests? Options: A) #KenyaRising B) #OccupyParliament C) #TaxRevolt D) #GenZFight Correct Answer: B) #OccupyParliament Explanation: The #OccupyParliament hashtag was widely used by protesters to rally against the Finance Bill 2024, as documented by the BBC. Question 8 Category: Entertainment Question: Which actor starred as the lead in the 2023 film Barbie and also played a role in La La Land? Options: A) Emma Stone B) Margot Robbie C) Zendaya D) Saoirse Ronan Correct Answer: B) Margot Robbie Explanation: Margot Robbie starred as Barbie in the 2023 film and played a supporting role in La La Land (2016). Question 9 Category: Sports Question: Which sport is played at the Wimbledon Championships? Options: A) Cricket B) Rugby C) Tennis D) Golf Correct Answer: C) Tennis Explanation: Wimbledon, held annually in London, is the oldest and one of the most prestigious tennis tournaments in the world. Question 10 Category: Technology Question: In web development, what does the acronym “CSS” stand for? Options: A) Computer Style System B) Cascading Style Sheets C) Creative Script Syntax D) Centralized Style Standard Correct Answer: B) Cascading Style Sheets Explanation: CSS (Cascading Style Sheets) is used to style and format the appearance of web pages written in HTML.Question 1: Role Allocation a. How did your team decide on the roles and responsibilities for each team member? 1. By drawing lots 2. By assigning roles based on personal preferences 3. By discussing and considering each member's skills and interests 4. By letting the team leader decide Question 2: Role Allocation b. Did everyone in the team contribute to defining their roles and responsibilities? 1. Yes, everyone had a say in defining their roles 2. No, only the team leader decided the roles 3. Only a few members contributed to defining roles 4. Roles were assigned by the instructor Question 3: Role Allocation c. How does each team member's role contribute to the overall project? 1. Each member's role is unrelated to the project 2. Each member's role is equally important for the project's success 3. Some roles are more important than others 4. The team did not define specific roles for each member Question 4: Communication a. Describe the communication tools and strategies your team used to collaborate effectively. 1. We only communicated through email 2. We used a combination of email, messaging apps, and face-to-face meetings 3. We relied solely on face-to-face meetings 4. We did not have any specific communication tools or strategies Question 5: Communication b. How did your team handle disagreements or conflicts in communication? 1. We avoided conflicts by not discussing disagreements 2. We had open discussions and found compromises 3. Conflicts were resolved by the team leader's decision 4. We did not encounter any conflicts in communication Question 6: Communication c. Did you have regular team meetings, and how did they contribute to your project's progress? 1. We had regular meetings, but they did not contribute to the project's progress 2. We had irregular meetings, which hindered the project's progress 3. We had regular meetings, and they significantly contributed to the project's progress 4. We did not have any team meetings Question 7: Problem Solving a. Can you provide an example of a challenging problem your team encountered during the project, and how did you work together to solve it? 1. We did not encounter any challenging problems 2. We encountered a problem, but did not work together to solve it 3. We encountered a problem and worked together to find a solution 4. We encountered a problem, but only the team leader solved it Question 8: Problem Solving b. Did your team encounter any technical roadblocks, and how did you collectively address them? 1. We did not encounter any technical roadblocks 2. We encountered roadblocks, but did not address them collectively 3. We encountered roadblocks and collectively found solutions 4. Only a few team members addressed the technical roadblocks Question 9: Problem Solving c. Were there any innovative solutions or ideas that emerged through team collaboration? 1. No, there were no innovative solutions or ideas 2. Yes, there were some innovative solutions or ideas 3. Only the team leader came up with innovative solutions or ideas 4. The team did not collaborate on finding solutions or ideas Question 10: Project Planning and Organization a. How did your team plan and manage tasks and deadlines throughout the project? 1. We did not have a plan or manage tasks and deadlines 2. We had a plan, but did not manage tasks and deadlines effectively 3. We had a plan and managed tasks and deadlines effectively 4. Only the team leader managed tasks and deadlines Answer Key: 1. c 2. a 3. b 4. b 5. b 6. c 7. c 8. c 9. b 10. c1. Battle of Lexington At the Battle of Lexington in 1775, British soldiers and colonial militia faced each other on the village green. A shot was fired, but no one knows for sure who fired first. Even so, this moment is often called the beginning of the American Revolution. Why is the Battle of Lexington still considered the start of the American Revolution, even though it is unclear who fired the first shot? A. It marked the first time colonists and British soldiers fought in open battle B. It proved that colonists planned the war long before the fighting began C. It showed that British soldiers were fully responsible for starting the war D. It confirmed that colonists had already declared independence from Britain 2. Battle of Concord After the fighting at Lexington, British troops marched to Concord to destroy colonial supplies. Instead, colonial militia gathered and fought back, forcing the British to retreat toward Boston. Why is the Battle of Concord considered an important turning point in the early American Revolution? A. It showed that colonial militias could organize and successfully push back British troops B. It proved that the British army had already lost control of all the colonies C. It confirmed that the colonies had officially declared independence from Britain D. It demonstrated that foreign countries were already helping the colonial forces 3. Second Continental Congress Much of the early violent conflict between colonists and British soldiers took place in Boston. After fighting broke out at Lexington and Concord near Boston, colonial leaders met at the Second Continental Congress in 1775 to decide what to do next. Which answer best describes the main actions taken by the Second Continental Congress? A. They created an army, chose a leader, and tried to avoid war with Britain B. They declared independence, wrote the Constitution, and ended the war C. They raised taxes, formed a monarchy, and supported British rule D. They ended slavery, gave women rights, and expanded voting laws 4. Olive Branch Petition In 1775, colonial leaders sent a letter called the Olive Branch Petition to King George III of Britain. Based on this situation, what was the main purpose of the Olive Branch Petition sent to the king? A. To ask the king to restore peace between both sides B. To declare independence from Britain and begin a new nation C. To request help from foreign countries in the war effort D. To organize protests against British taxes across the colonies 5. Battle of Bunker Hill On June 17, 1775, during the Battle of Bunker Hill in Boston, colonial forces fought against the British on a hill overlooking the city. The fighting was intense and led to heavy losses on both sides. Which statement best explains why the Battle of Bunker Hill was an important battle in the war? A. The colonists won the battle, showing they were stronger than British forces B. The colonists won the battle, showing the British that the war would be short and easy for the colonists C. The British won the battle, showing the war would be difficult and costly for both sides D. The British won the battle, showing British forces could defeat the colonists easily 6. Pamphlets During the American Revolution, pamphlets were short printed writings that were inexpensive to produce and often written in everyday language so many colonists could read them. How did these features of pamphlets most affect their role in the American Revolution? A. They helped spread ideas widely, allowing more colonists to form and share opinions B. They limited ideas to educated leaders, keeping most colonists uninvolved C. They replaced newspapers entirely, becoming the only source of information D. They prevented disagreement, causing most colonists to think the same way 7. Thomas Paine’s Common Sense In 1776, Thomas Paine published Common Sense, a widely read piece of writing about the relationship between the colonies and Britain. How did this pamphlet most influence colonial thinking during the American Revolution? A. It encouraged colonists to support independence from Britain B. It convinced colonists to remain loyal to the British government C. It explained how colonial armies should organize attacks D. It described laws colonists were expected to follow 8. Declaration of Independence In July 1776, the Declaration of Independence listed complaints against King George III and explained the colonists’ ideas about government and rights. How do these parts of the Declaration of Independence work together to support the colonists’ decision? A. They connect ideas about rights to real examples, justifying separation from Britain B. They describe past events in detail, showing how the war had already ended C. They list future plans for government, explaining how leaders would be chosen D. They organize military actions, showing how the colonies planned to win 9. Washington Crosses the Delaware and Battle of Trenton In December 1776, George Washington led his army across the Delaware River and launched a surprise attack on Hessian mercenaries in Trenton. Which statement best explains why Washington’s crossing of the Delaware and the attack on Trenton was an important turning point in the war? A. It defeated British forces completely, ending the war in a short time B. It boosted morale, helping discouraged soldiers choose to keep fighting C. It brought foreign allies into the war, adding support for the colonies D. It led to independence, allowing the colonies to form a new nation 10. Battle of Saratoga In 1777, American forces defeated the British at the Battle of Saratoga, a major event during the American Revolution. Which statement best explains why the Battle of Saratoga was an important turning point in the war? A. It brought French support, helping Americans gain a strong advantage in the war B. It ended the war quickly, forcing Britain to surrender all control in the colonies C. It improved army training, helping soldiers become more skilled in future battles D. It changed leadership roles, causing new generals to take control of the army 11. Battle of Yorktown In 1781, American forces surrounded British troops at Yorktown, leading to a major moment in the American Revolution. Which statement best explains why the Battle of Yorktown was an important event in the war? A. French forces helped the Americans win, leading to the end of major fighting in the war B. Italian forces helped the British win, leading to a final victory over the American army C. German forces switched sides and helped the Americans win, leading to a final defeat for British troops D. French forces helped the British win, leading to a complete end of the war in the colonies 12. Treaty of Paris After the Battle of Yorktown, British public opinion turned against the war, and peace negotiations began. In 1783, American leaders signed the Treaty of Paris, which included agreements between the United States and Britain. Which statement best explains how the Treaty of Paris reflected the outcome of the American Revolution? A. Both sides made agreements, recognizing independence B. Americans gained independence, taking land without agreements C. British leaders kept control, ending the war with power D. Both sides refused compromise, continuing the war1.Linguistics is the science that studies language. 2.Linguist:Someone who studies linguistics. 3.The Subfields of Linguistics Phonetics deals with the sounds of language. Phonology deals with how the sounds are organized. Morphology deals with how sounds are put together to form words. Syntax deals with how sentences are formed. Semantics deals with the meaning of words, sentences, and texts. Pragmatics deals with how sentences and texts are used in the world (i.e., in context) Text Linguistics deals with units larger than sentences, such as paragraphs and texts. 4.Prescriptive: This approach consists basically of stating what is considered right and wrong in language. 5.Descriptive: This approach, on the other hand, consists of describing the facts. Descriptive linguistics is dedicated to describing the rules of the language, and the language is seen as essentially rule governed. 6.Language is rule-governed, creative, universal, innate, and learned, all at the same time. 7.Linguists understand language as a system of arbitrary vocal signs. 8.Linguistic signs: involve sequences of sounds which represent concrete objects and events as well as abstractions.Signs may be related to the things they represent in a number of ways. 9.Iconic: which resemble the things they represent (as do, for example, photographs, diagrams, star charts, or chemical models). 10.Indexical: which point to or have a necessary connection with the things they represent (as do, for example, smoke to fire, a weathercock to the direction of the wind, a symptom to an illness, a smile to happiness, or a frown to anger). 11.Describe the characteristics of human language: Creative: (The structural elements of human language can be combined to produce new utterances, which neither the speaker nor his hearers may ever have made or heard before.) Rule-governed: (Language is made of rules.) Universal: (There are some aspects that are present in all languages of the world.) Innate:(all humans possess an innate capacity for language, activated in infancy by minimal environmental stimuli. Chomsky) Uniquely human: (Language is what sets us apart from other species. It is what makes us human.) Learned:(Children acquire language from their natural setting.) 12.Differentiate between iconic, indexical and symbolic signs. A. iconic, which resemble the things they represent (as do, for example, photographs, diagrams, star charts, or chemical models) B. indexical, which point to or have a necessary connection with the things they represent (as do, for example, smoke to fire, a weathercock to the direction of the wind, a symptom to an illness, a smile to happiness, or a frown to anger). c. symbolic, which are only conventionally related to the thing they represent (as do, for example, a flag to a nation, a rose to love, a wedding ring to marriage). 12. Distinguish between different senses of the grammar word. The prescriptivist´s grammar (Grammar is a set of rules that label the different utterances as either right or wrong.) The descriptivist´s grammar (Grammar is a set of rules that govern the langauge spoken by people. ) The linguist´s grammar (Grammar is the subconscious knowledge of the set of rules that enables speakers to use the language) The speaker´s grammar (Grammar is the intrinsic linguistic knowledge within a native speaker) 13.Describe common fallacies about language and grammar: ►One type of grammar is simpler than another. ►Changes in grammar involve deterioration in a language ►Grammars should be logical and analogical (that is, regular) ►People must be taught the grammatical rules of their language. ►Only some languages have grammar. ►Grammars differ from each other in unpredictable ways. 14.Generality: All Languages Have a Grammar 15. Equality: All Grammars Are Equal 16.Changeability: Grammars Change Over Time 17. Universality: Grammars Are Alike in Basic Ways 18.Tacitness: Grammatical Knowledge Is Subconscious 19.Linguistics is defined as the study of language systems. It is the scientific study of language. 20.Historical approach:It is the study of language change. 21.Linguistic Competence: is the unconscious knowledge speakers of a language have about the system that enables them to create and understand novel utterances. 22.Performance: is the use of it. Performance is “the actual use of language in concrete situations.” 23.I-Language (internal language): which is the intrinsic linguistic knowledge within a native speaker. 24.E-Language (external language): which is the observable language—the output from a speaker. 25.Parole ('speech') refers to the concrete instances of the use of langue, including texts which provide the ordinary research material for linguistics. 26.Langue: 27.Language: is a system of communication that is non-stereotyped and non-finite; it is unlimited in its scope. 28.Grammar: to refer to a subconscious linguistic system of a particular type. Grammar makes possible the production and comprehension of a potentially unlimited number of utterances. 29.Communication and animals: Selecting a mode of communication (speech,writing, gesture). Delivering the symbols through a medium, a physical basis for communication, light, air, or ink. Decoding of the symbols to obtain the information. 30.SIGNS: Communication relies on using something to stand for something else. Words are an obvious example of this: You do not have to have a car, a sandwich, or your cousin present in order to talk about them—the words car, sandwich, and cousin stand for them instead. This same phenomenon is found in animal communication as well. 31.The signifier: A signifier is that part of a sign that stimulates at least one sense organ of the receiver of a message.A signifier can also be a picture, a photograph, a sign language gesture, or one of the many other words for tree in different languages. 32.The signified: The signified component of the sign refers to both the real world object it represents and its conceptual content. The first of these is the real world content of the sign, its extension or referent within a system of signs such as English, avian communication, or sign language. 33.Iconic signs or icons: always bear some resemblance to their referent. A photograph is an iconic sign; so too is a stylized silhouette of a female or a male on a restroom door. 34.Some iconic tokens: a. open-mouth threat by a Japanese macaque; b. park recreation signs; c. onomatopoeic words in English. 35.An indexical sign, or index, fulfils its function by pointing out its referent, typically by being a partial or representative sample of it. Indexes are not arbitrary, since their presence has in some sense been caused by their referent. For this reason it is sometimes said that there is a causal link between an indexical sign and its referent.The track of an animal, for example, points to the existence of the animal by representing a part of it. The presence of smoke is an index of fire. 36.Symbolic signs: bear an arbitrary relationship to their referents and in this way are distinct from both icons and indexes. Human language is highly symbolic in that the vast majority of its signs bear no inherent resemblance or causal connection to their referents, as the following words show. 37.Mixed signs Signs: are not always exclusively of one type or another. Symptomatic signs, for example, may have iconic properties, as when a dog opens its mouth in a threat to bite. Symbolic signs such as traffic lights are symptomatic in that they reflect the internal state of the mechanism that causes them to change color. 38.Signals: All signs can act as signals when they trigger a specific action on the part of the receiver, as do traffic lights, words in human language such as the race starter's "Go!", or the warning calls of birds. 39.SIGN STRUCTURE: No matter what their type, signs show different kinds of structure. A basic distinction is made between graded and discrete sign structure. 40.Graded signs convey their meaning by changes in degree. A good example of a gradation in communication is voice volume. The more you want to be heard, the louder you speak along an increasing scale of loudness. There are no steps or jumps from one level to the next that can be associated with a specific change in meaning. 41.Discrete signs are distinguished from each other by categorical (stepwise) differences. There is no gradual transition from one sign to the next. The words of human language are good examples of discrete signs. 42.A VIEW OF ANIMAL COMMUNICATION ►Largely iconic ►Largely symptomatic ►Little arbitrary ►Not deliberate ►Not conscious ►Not symbolic ►Stimulus bound