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Solar Energy in Domestic Homes
Quiz by Jose Vasco HernÔndez
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Escape from Unsuitable Conditions Some species can survive unfavorable environmental conditions by escaping from them temporarily. For example, desert animals usually hide underground or in the shade during the hottest part of the day. Many desert species are active at night, when temper- atures are much lower. A longer-term strategy is to enter a state of reduced activity, called dormancy, during periods of unfavorable conditions, such as winter or drought. Another strategy is to move to a more favorable habitat, called migration. An example of migration is the seasonal movements of birds, which spend spring and summer in cooler climates and migrate to warmer climates in the fall. THE NICHE Species do not use or occupy all parts of their habitat at once. The specific role, or way of life, of a species within its environment is its niche (NICH). The niche includes the range of conditions that the species can tolerate, the resources it uses, the methods by which it obtains resources, the number of offspring it has, its time of reproduction, and all other interactions with its environment. Parts of a lionās niche are shown in Figure 18-6. Generalists are species with broad niches; they can tolerate a range of conditions and use a variety of resources. An example of a generalist is the Virginia opossum, found across much of the United States. The opossum feeds on almost anything, from eggs and dead animals to fruits and plants. In contrast, species that have narrow niches are called specialists. An example is the koala of Australia, which feeds only on the leaves of a few species of eucalyptus trees. Some species have more than one niche within a lifetime. For example, caterpillars eat the leaves of plants, but as adult butter- flies, they feed on nectar. Plants and animals are able to share the same habitats because they each have different niches. FIGURE 18-6 niche from the Old French nichier, meaning āto nestā Word Roots and Origins www.scilinks.org Topic: Niche/Habitats Keyword: HM61029 mb06se_iecs02.qxd 5/24/07 10:25 AM Page 365 366 CHAPTER 18 ENERGY TRANSFER All organisms need energy to carry out essential functions, such as growth, movement, maintenance and repair, and reproduction. In an ecosystem, energy flows from the sun to autotrophs, then to organisms that eat the autotrophs, and then to organisms that feed on other organisms. The amount of energy an ecosystem receives and the amount that is transferred from organism to organism affect the ecosystemās structure. PRODUCERS Autotrophs, which include plants and some kinds of protists and bacteria, manufacture their own food. Because autotrophs cap- ture energy and use it to make organic molecules, they are called producers. Recall that organic molecules are molecules that con- tain carbon. Most producers are photosynthetic, so they use solar energy to power the production of food. However, some autotrophic bacteria do not use sunlight as an energy source. These bacteria carry out chemosynthesis (KEE-moh-SIN-thuh-sis), in which they use energy stored in inorganic molecules to produce carbohydrates. In terres- trial ecosystems, plants are usually the major producers. In aquatic ecosystems, photosynthetic protists and bacteria are usu-
Grace Hopper (1906-1992): An American computer scientist and U.S. Navy rear admiral. She was a pioneer in computer programming and developed the first compiler for a computer programming language, laying the groundwork for cobol. Garrett Augustus Morgan Sr. (1877-1963): An African American inventor who patented the traffic signal and the safety hood, a precursor to the modern gas mask. Hedy Lamarr (1914-2000): An Austrian-American actress and inventor who co-invented an early technique for spread spectrum communications, a key to modern wifi and bluetooth technology. Otis Boykin (1920-1982): An African American inventor who patented over 25 electronic devices, including a control unit for the pacemaker that is widely used today. Stephanie Kwolek (1923-2014): An American chemist who invented the synthetic fiber Kevlar, which is used in bulletproof vests and other protective equipment. Gladys West (b. 1930): An African American mathematician who played a crucial role in the development of the GPS technology we use today. Shirley Ann Jackson (b. 1946): An African American physicist who was the first African American woman to receive a doctorate at MIT and her work laid the foundations for the touch-tone telephone, caller ID, and call waiting. Tu Youyou (b. 1930): A Chinese pharmaceutical chemist who discovered artemisinin, a drug therapy that has significantly reduced the mortality rates for malaria, for which she was awarded the Nobel Prize in Physiology or Medicine in 2015. Chien-Shiung Wu (1912-1997): A Chinese-American physicist who made significant contributions to the Manhattan Project and disproved the hypothetical law of conservation of parity, for which her male colleagues received the Nobel Prize (she did not). MĆ”ria Telkes (1900-1995): A Hungarian-American biophysicist and architect dubbed the "Sun Queen" for her pioneering work in solar energy, including the development of the first solar-powered house. Percy Lavon Julian (1899-1975): An African American chemist and pioneer in the chemical synthesis of medicinal drugs from plants. Charles Ginsburg (1925-1992): An American engineer who led the team that developed the first commercial videotape recorder. Philo Farnsworth (1906-1971): An American inventor who developed an electronic television system and made major contributions to early television technology. MarĆa Montoya MartĆnez (1887-1980): A Native American (Tewa) potter from San Ildefonso Pueblo, New Mexico, who helped revive the traditional black-on-black pottery style and is considered one of the most influential Pueblo potters of the 20th century. Satya Nadella (b. 1967): An Indian-American business executive who has been the chief executive officer of Microsoft since 2014, overseeing the company's transformation into a cloud computing powerhouse. Junko Tabei (1939-2016): A Japanese mountaineer who in 1975 became the first woman to reach the summit of Mount Everest, and the first woman to ascend the Seven Summits, climbing the highest peaks on each continent. Mildred Dresselhaus (1930-2017): An American physicist and engineer, known as the "Queen of Carbon Science," who made groundbreaking contributions to the study of carbon materials like graphite and carbon nanotubes. Ellen Ochoa (b. 1958): An American engineer and former astronaut. In 1993, she became the first Hispanic woman to go to space when she flew on the Space Shuttle Discovery. FranƧoise BarrĆ©-Sinoussi (b. 1947): A French virologist who co-discovered HIV as the cause of AIDS, for which she was awarded the Nobel Prize in Physiology or Medicine in 2008. Esther Lederberg (1922-2006): An American microbiologist who made significant contributions to genetics and microbiology, including the discovery of the bacterial virus lambda, but whose work was often overshadowed by her husband's Nobel Prize-winning accomplishments.
1. Identify a Research Problem/Topic What to Explain: The first step in research is finding a problem or topic that needs investigation. A good research problem should be specific, relevant, feasible, and original. Examples: Broad Topic: Renewable Energy. Problem: "How can solar energy efficiency be improved in high-humidity areas?" Broad Topic: Mental Health. Problem: "What is the impact of remote work on anxiety levels in young professionals?" Activity Suggestion: Ask students to brainstorm broad topics they are interested in and narrow them down into researchable problems. 2. Conduct a Literature Review What to Explain: This step involves reviewing existing research to understand whatās already known and to identify gaps in knowledge. It ensures youāre building on prior work and not duplicating efforts. How to Conduct: Use credible sources (e.g., Google Scholar, JSTOR). Take notes on key findings and gaps. Summarize patterns or contradictions in existing research. Examples: If researching "urban heat islands," your literature review might show studies focusing on large cities but identify a gap in smaller towns. Activity Suggestion: Provide an abstract of a research paper and ask students to identify key findings and gaps.
What is a Plant Cell? Plant cells are eukaryotic cells that vary in several fundamental factors from other eukaryotic organisms. Both plant and animal cells contain a nucleus along with similar organelles. One of the distinctive aspects of a plant cell is the presence of a cell wall outside the cell membrane. Plant Cell Structure Just like different organs within the body, plant cell structure includes various components known as cell organelles that perform different functions to sustain itself. These organelles include: Cell Wall It is a rigid layer which is composed of polysaccharides cellulose, pectin and hemicellulose. It is located outside the cell membrane. It also comprises glycoproteins and polymers such as lignin, cutin, or suberin. The primary function of the cell wall is to protect and provide structural support to the cell. The plant cell wall is also involved in protecting the cell against mechanical stress and providing form and structure to the cell. It also filters the molecules passing in and out of it. The formation of the cell wall is guided by microtubules. It consists of three layers, namely, primary, secondary and the middle lamella. The primary cell wall is formed by cellulose laid down by enzymes. Cell membrane It is the semi-permeable membrane that is present within the cell wall. It is composed of a thin layer of protein and fat. The cell membrane plays an important role in regulating the entry and exit of specific substances within the cell. For instance, cell membrane keeps toxins from entering inside, while nutrients and essential minerals are transported across. Nucleus The nucleus is a membrane-bound structure that is present only in eukaryotic cells. The vital function of a nucleus is to store DNA or hereditary information required for cell division, metabolism and growth. 1. Nucleolus: It manufactures cellsā protein-producing structures and ribosomes. 2. Nucleopore: Nuclear membrane is perforated with holes called nucleopore that allow proteins and nucleic acids to pass through. Plastids They are membrane-bound organelles that have their own DNA. They are necessary to store starch and to carry out the process of photosynthesis. It is also used in the synthesis of many molecules, which form the building blocks of the cell. Some of the vital types of plastids and their functions are stated below: Leucoplasts They are found in the non-photosynthetic tissue of plants. They are used for the storage of protein, lipid and starch. Chromoplasts They are heterogeneous, colored plastid which is responsible for pigment synthesis and for storage in photosynthetic eukaryotic organisms. Chromoplasts have red-, orange- and yellow-colored pigments which provide color to all ripe fruits and flowers. Central Vacuole It occupies around 30% of the cellās volume in a mature plant cell. Tonoplast is a membrane that surrounds the central vacuole. The vital function of the central vacuole apart from storage is to sustain turgor pressure against the cell wall. The central vacuole consists of cell sap. It is a mixture of salts, enzymes and other substances. Golgi Apparatus They are found in all eukaryotic cells, which are involved in distributing synthesized macromolecules to various parts of the cell. Ribosomes They are the smallest membrane-bound organelles which comprise RNA and protein. They are the sites for protein synthesis, hence, also referred to as the protein factories of the cell. Mitochondria They are the double-membraned organelles found in the cytoplasm of all eukaryotic cells. They provide energy by breaking down carbohydrate and sugar molecules, hence they are also referred to as the āPowerhouse of the cell.ā Lysosome Lysosomes are called suicidal bags as they hold digestive enzymes in an enclosed membrane. They perform the function of cellular waste disposal by digesting worn-out organelles, food particles and foreign bodies in the cell. In plants, the role of lysosomes is undertaken by the vacuoles. Chloroplasts It is an elongated organelle enclosed by phospholipid membrane. The chloroplast is shaped like a disc and the stroma is the fluid within the chloroplast that comprises a circular DNA. Each chloroplast contains a green colored pigment called chlorophyll required for the process of photosynthesis. The chlorophyll absorbs light energy from the sun and uses it to transform carbon dioxide and water into glucose. Structure of Chloroplast Chloroplasts are found in all higher plants. It is oval or biconvex, found within the mesophyll of the plant cell. The size of the chloroplast usually varies between 4-6 µm in diameter and 1-3 µm in thickness. They are double-membrane organelle with the presence of outer, inner and intermembrane space. There are two distinct regions present inside a chloroplast known as the grana and stroma. ⢠Grana are made up of stacks of disc-shaped structures known as thylakoids or lamellae. The granum of the chloroplast consists of chlorophyll pigments and are the functional units of chloroplasts. ⢠Stroma is the homogenous matrix which contains grana and is similar to the cytoplasm in cells in which all the organelles are embedded. Stroma also contains various enzymes, DNA, ribosomes, and other substances. Stroma lamellae function by connecting the stacks of thylakoid sacs or grana. The chloroplast structure consists of the following parts: Membrane Envelope It comprises inner and outer lipid bilayer membranes. The inner membrane separates the stroma from the intermembrane space. Intermembrane Space The space between inner and outer membranes. Thylakoid System (Lamellae) The system is suspended in the stroma. It is a collection of membranous sacs called thylakoids or lamellae. The green colored pigments called chlorophyll are found in the thylakoid membranes. It is the sight for the process of light-dependent reactions of the photosynthesis process. The thylakoids are arranged in stacks known as grana and each granum contains around 10-20 thylakoids. Stroma It is a colorless, alkaline, aqueous, protein-rich fluid present within the inner membrane of the chloroplast present surrounding the grana. Grana Stack of lamellae in plastids is known as grana. These are the sites of conversion of light energy into chemical energy. Chlorophyll It is a green photosynthetic pigment that helps in the process of photosynthesis. Functions of Chloroplast Following are the important chloroplast functions: ⢠The most important function of the chloroplast is to synthesize food by the process of photosynthesis. ⢠Absorbs light energy and converts it into chemical energy. ⢠Chloroplast has a structure called chlorophyll which functions by trapping the solar energy and is used for the synthesis of food in all green plants. ⢠Produces NADPH and molecular oxygen (O 2 ) by photolysis of water. ⢠Produces ATP ā Adenosine triphosphate by the process of photosynthesis. ⢠The carbon dioxide (CO2) obtained from the air is used to generate carbon and sugar during the Calvin Cycle or dark reaction of photosynthesis. Mitochondria āMitochondria are membrane-bound organelles present in the cytoplasm of all eukaryotic cells, that produce adenosine triphosphate (ATP), the main energy molecule used by the cell.ā What are Mitochondria? Popularly known as the āPowerhouse of the cell,ā mitochondria (singular: mitochondrion) are a double membrane-bound organelle found in most eukaryotic organisms. They are found inside the cytoplasm and essentially function as the cellās ādigestive system.ā They play a major role in breaking down nutrients and generating energy-rich molecules for the cell. Many of the biochemical reactions involved in cellular respiration take place within the mitochondria. The term āmitochondrionā is derived from the Greek words āmitosā and āchondrionā which means āthreadā and āgranules-likeā, respectively. It was first described by a German pathologist named Richard Altmann in the year 1890. Structure of Mitochondria ⢠The mitochondrion is a double-membraned, rod-shaped structure found in both plant and animal cell. ⢠Its size ranges from 0.5 to 1.0 micrometers in diameter. ⢠The structure comprises an outer membrane, an inner membrane, and a gel-like material called the matrix. ⢠The outer membrane and the inner membrane are made of proteins and phospholipid layers separated by the intermembrane space. ⢠The outer membrane covers the surface of the mitochondrion and has a large number of special proteins known as porins. Cristae The inner membrane of mitochondria is rather complex in structure. It has many folds that form a layered structure called cristae, and this helps in increasing the surface area inside the organelle. The cristae and the proteins of the inner membrane aid in the production of ATP molecules. The inner mitochondrial membrane is strictly permeable only to oxygen and ATP molecules. A number of chemical reactions take place within the inner membrane of mitochondria. Mitochondrial Matrix The mitochondrial matrix is a viscous fluid that contains a mixture of enzymes and proteins. It also comprises ribosomes, inorganic ions, mitochondrial DNA, nucleotide cofactors, and organic molecules. The enzymes present in the matrix play an important role in the synthesis of ATP molecules. Functions of Mitochondria The most important function of mitochondria is to produce energy through the process of oxidative phosphorylation. It is also involved in the following process: 1. Regulates the metabolic activity of the cell 2. Promotes the growth of new cells and cell multiplication 3. Helps in detoxifying ammonia in the liver cells 4. Plays an important role in apoptosis or programmed cell death 5. Responsible for building certain parts of the blood and various hormones like testosterone and estrogen 6. Helps in maintaining an adequate concentration of calcium ions within the compartments of the cell 7. It is also involved in various cellular activities like cellular differentiation, cell signaling, cell senescence, controlling the cell cycle and in cell growth. Disorders Associated with Mitochondria Any irregularity in the way mitochondria function can directly affect human health, but often, it is difficult to identify because symptoms differ from person to person. Disorders of the mitochondria can be quite severe; in some cases, they can even cause an organ to fail.
Based on the provided sources, here is a comprehensive extraction of the information regarding the water cycle, energy transfer, and Earth's wind systems, organized into key points: The Water Cycle and Its Reservoirs ⢠Definition: The water cycle is the continuous movement of water among various reservoirs on Earth. ⢠Water Reservoirs: These are storage locations for water and include: ⦠Oceans, seas, and lakes. ⦠Rivers, glaciers, soil, and rocks. ⦠The atmosphere and living organisms. ⢠Total Volume: The total amount of water on Earth does not change, even when it changes state, because it is constantly being replaced or recycled through the cycle. Main Processes and Energy Transfer The movement of water through the cycle is driven by energy (thermal energy from the Sun) and force (gravity and wind). ⢠Energy Gain (Absorption): ⦠Melting: Water changes from a solid state (ice) to a liquid state and gains energy. ⦠Evaporation: Liquid water changes into a gas state (water vapor) by gaining thermal energy. ⦠Transpiration: A specialized type of evaporation occurring in plants where water vapor is released through tiny holes in leaves called stomata. Approximately 10% of water vapor in the air comes from transpiration. ⢠Energy Loss (Release): ⦠Condensation: Water vapor (gas) cools down and changes back into liquid water, releasing energy. ⦠Freezing: Liquid water changes into a solid state (ice) and loses energy. ⢠Other Key Steps: ⦠Precipitation: Water falls back to Earth as rain, snow, sleet, or hail (snow pellets). ⦠Runoff: Water flows over Earth's surface into streams, rivers, and eventually larger bodies of water like oceans. ⦠Collection: Rainwater is collected in different water bodies to start the cycle again. Forces Driving Water Movement ⢠Gravity: The main force that pulls water downward. It is responsible for: ⦠Bringing precipitation (rain and snow) from clouds to the surface. ⦠Moving ice in glaciers from higher to lower elevations. ⦠Causing liquid water to flow downhill into rivers and seas. ⦠Leakage: Pulling liquid water down into the ground to reach groundwater reservoirs. ⢠Wind: Another force that affects water movement and transports water to different locations on Earth. Atmospheric Processes ⢠Cloud Formation: Water vapor attaches to particles such as dust or smoke in the air and condenses into tiny droplets. When millions of these droplets join, they become heavy and fall as rain. ⢠Convection: The transfer of heat in liquids and gases. ⦠Warm air/liquid: Becomes less dense, lighter, and rises upward. ⦠Cold air/liquid: Is more dense, heavier, and moves downward to replace the warm fluid. ⦠This process leads to convection currents, which help determine regional climates and drive wind and ocean currents. Solar Radiation and Climate The amount of solar energy reaching Earth differs from place to place, which affects the weather: ⢠Hottest Regions (Equator): Sun rays fall perpendicular (vertical). Heat is concentrated on a small area, making the weather hot. ⢠Moderate Regions: Sun rays fall semi-inclined. Heat is distributed over a larger area, making the weather warm. ⢠Coolest Regions (Poles): Sun rays fall very slanted (inclined). Heat is spread over a very large area, making the weather very cold. Earth's Wind System ⢠Wind Formation: Wind is generated when warm air (heated by the Sun) rises and is replaced by cooler air flowing from nearby areas. ⢠Factors Affecting Wind: The amount of solar radiation and the rotation of Earth determine global wind directions. ⢠Global Wind Cycle: Unequal heating between the equator and the poles generates a constant wind system. Warm air rises at the equator and moves toward the poles, while cold air from the poles moves toward the equator. ⢠Importance: If there were no wind, the equator would become extremely hot, the poles would freeze solid, and many ecosystems would disappear. Practical Examples ⢠Turkeyās Salt Lake: High evaporation in the summer can turn this large lake into a small puddle or dry it up completely. It is a critical site for flamingos, which migrate there to breed and feed on algae in the shallow, warm water.
Welcome, Carlos! One late summer day, Carlos sat at the kitchen table. He wanted to begin his poster. He had found paper, glue, and colored markers. He had a box of family photoS. But what should I put on it? he thought. Soon, Carlos would start school in a new town, in a new country. He had just met his new school principal. "You can bring this poster on the first day of school, Carlos," his principal had said. "This will help the kids get to know you." Carlos picked photos of his family. He added one of their old home in Monterrey, Mexico. He wrote about the books, sports, and foods he liked. He carried his poster across the hall of his apartment building. He knocked on the door, and a smiling girl opened it. "Hola, Carlos!" said Maria. "Hola, Maria," said Carlos. "Do you want to see my poster? It's for the first day of school." "Oh, yes!" said Maria. Carlos spread out the poster. "This is a photo of my parents," Carlos explained. "This is our house. These are the mountains in Monterrey." "My padre works for a big solar energy company from Monterrey. They moved us to the United States to open a new factory here." "Monterrey looks beautiful, Carlos," said Maria. "It was sunny and a great place to do things outdoors," Carlos said. "Was it hard to leave your relatives?" Maria asked. "Yes, but we'll go back during the holidays to visit them," said Carlos. Maria looked at another photo. "That's my older brother, Mateo. This is my little sister, Selena," Carlos said. "My abuela will come to live with us soon, too." Maria read that Carlos liked to play baseball. "You could join our baseball team!" said Maria. "That would be fun," said Carlos. He showed Maria his best batting swing. "That's a good hit, for sure!" laughed Maria. Then Maria brought out crayons and markers. Together they colored the rest of the poster. "There's something I want to add," said Carlos. Carlos drew a picture of a smiling girl. She had long, soft hair. "Is that your friend in Monterrey?" asked Maria. "No, it's my first friend in America!" said Carlos.