Biology I. Chapter 8/9

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1 Biology I Chapter 8/9

2 Interest Grabber NOTEBOOK #1 Suppose you earned extra money by having a part-time job. At first, you might be tempted to spend all of the money, but then you decide to open a bank account. 1. What are the benefits of having a bank account? 2. What do you have to do if you need some of this money? 3. What might your body do when it has more energy than it needs to carry out its activities? 4. What does your body do when it needs energy?

3 Interest Grabber Answers What are the benefits of having a bank account? To save money and earn interest. What do you have to do if you need some of this money? Go to the bank and take out the money you need. 3. What might your body do when it has more energy than it needs to carry out its activities? 4. Students will likely say that the body stores the energy. What does your body do when it needs energy? Student answers may include that energy is gotten from food.

4 Autotrophs All living things need and use energy. Living things get this energy from food, but the energy in the food ultimately comes from the sun. Plants and some other types of organisms are able to use light energy from the sun to produce food. Organisms that can make their own food are called Autotrophs.

5 Heterotrophs Organisms, such as animals, can not directly use the sun s energy. Organisms that obtain energy from the food they consume are called heterotrophs.

6 Chemical Energy in ATP Living things use chemical fuels. The principal chemical compound that cells use to store and release energy is adenosine triphosphate (ATP). ATP is made up of 3 main parts: 1. Adenine 2. 5-carbon sugar (ribose) 3. 3 phosphate groups The phosphate groups are the key to ATP s ability to store and release energy.

7 ATP Adenine Ribose 3 Phosphate groups

8 Comparison of ADP and ATP to a battery ADP ATP Energy Energy Adenosine triphosphate (ATP) Partially charged battery Fully charged battery

9 Releasing Energy How do cells get energy from ATP? The cell simply breaks the bond between the second and third phosphate groups. The energy released can power active transport, protein synthesis, and muscle contractions. The characteristics of ATP make it exceptionally useful as the basic energy source of all cells.

10 Interest Grabber NOTEBOOK #2 Trapping Energy Have you ever used a solar-powered calculator? No matter where you go, as long as you have a light source, the calculator works. You never have to put batteries in it.

11 Interest Grabber Cont. NOTEBOOK #2 1. A solar-powered calculator uses solar cells that are found in rows along the top of the calculator. Into what kind of energy is the light energy converted so that the calculator works? 2. Recall that plants use light energy from the sun to make food. Into what kind of energy is the light energy converted by plants? 3. Most plants, no matter what size or shape they are, have some parts that are green. Which parts of a plant are usually green? 4. What does the green color have to do with the plant s ability to convert light energy into the energy found in the food it makes?

12 Interest Grabber Answers 1. A solar-powered calculator uses solar cells that are found in rows along the top of the calculator. Into what kind of energy is the light energy converted so that the calculator works? They convert light energy into electrical energy. 2. Recall that plants use light energy from the sun to make food. Into what kind of energy is the light energy converted by plants? Plants convert light energy into chemical energy. 3. Most plants, no matter what size or shape they are, have some parts that are green. Which parts of a plant are usually green? Leaves are green, as are some stems. 4. What does the green color have to do with the plant s ability to convert light energy into the energy found in the food it makes? The green color is the pigment chlorophyll, which absorbs light energy from the sun and converts it to chemical energy in the process of photosynthesis.

13 The Photosynthesis Equation Photosynthesis uses the energy of sunlight to convert water and carbon dioxide into high-energy sugars and oxygen. The equation is:

14 Photosynthesis: Reactants and Products Light Energy Chloroplast CO 2 + H 2 O Sugars + O 2

15 Light and Pigment How do plants use energy from the sun? Energy from the sun travels to Earth in the form of light. You perceive the light as white, but it is made up of a spectrum of colors. Plants gather the sun s energy with light-absorbing molecules called pigments. The main pigment in plants is chlorophyll. Chlorophyll absorbs blue-violet and red light very well, but not green. Green light is reflected by leaves which is why they appear green. The energy absorbed by chlorophyll is transferred directly to electrons raising the energy level of those electrons.

16 Chlorophyll Light Absorption Absorption of Light by Chlorophyll a and Chlorophyll b V B G Y O R

17 NOTEBOOK #3 1. What three things make up an ATP molecule? 2. What is the difference between ADP and ATP? 3. What are the products of photosynthesis? 4. In what organelle does photosynthesis take place?

18 Interest Grabber A Look Into the Future NOTEBOOK #4 It is 100 years in the future and you are a research scientist. An enormous volcanic eruption has recently sent huge quantities of dust and ash into the atmosphere. Working with a partner, make a list of how this event will affect each of the following: 1. photosynthesis 2. plant life 3. animal life 4. human societies

19 Interest Grabber Answers Working with a partner, make a list of how this event will affect each of the following: 1. photosynthesis The rate of photosynthesis will decrease due to reduced sunlight. 2. plant life Plants will grow more slowly or die off due to decreased rate of photosynthesis. 3. animal life Animal populations will decrease after a while due to fewer plants for herbivores to eat. Fewer herbivores will eventually result in fewer carnivores. Also, less oxygen will be available. 4. human societies Human societies will have to adjust their eating habits as some food species die out.

20 Inside a Chloroplast Chloroplasts contain saclike photosynthetic membranes called thylakoids. Thylakoids are arranged in stacks called grana. Proteins in the thylakoid membrane organize chlorophyll into clusters called photosystems which collect the light from the sun.

21 Electron Carriers When light excites electrons to make a high energy electrons, they require a special carrier. Cells use a carrier molecule that will accept a pair of high-energy electrons and transfer them to other molecules. This is called electron transport. Photosynthesis uses a molecule called NADP +. NADP + accepts 2 electrons and a hydrogen ion to form a NADPH molecule.

22 Concept Map Photosynthesis includes use Lightdependent reactions take place in takes place in Calvin cycle uses Energy from sunlight Thylakoid membranes Stroma ATP NADPH to produce of to produce ATP NADPH O 2 Chloroplasts High-energy sugars

23 Photosynthesis: An Overview Light CO 2 Chloroplast Chloroplast NADP + ADP + P Stroma Light- Dependent Reactions ATP Calvin Cycle NADPH Thylakoidsstacks: grana O 2 Sugars

24 Light-Dependent Reaction -produces oxygen gas and converts ADP and NADP into the energy carriers ATP and NADPH (nicotinamide adenine dinucleotide phosphate) Photosystem II Hydrogen Ion Movement ATP synthase Chloroplast Inner Thylakoid Space Thylakoid Membrane Stroma Electron Transport Chain Photosystem I ATP Formation

25 Calvin Cycle -uses ATP and NADPH from the light-dependent reactions to produce high-energy sugars CO 2 Enters the Cycle Energy Input ChloropIast 5-Carbon Molecules Regenerated 6-Carbon Sugar Produced Sugars and other compounds

26 NOTEBOOK #5 (End of Chapter 8) 1. What two reactions are included in photosynthesis? 2. What is the stroma? 3. What is a thylakoid? 4. What do you call stacks of thylakoids? 5. What are the light-dependent reactions? 6. What is the Calvin Cycle?

27 Interest Grabber NOTEBOOK #6 Feel the Burn Do you like to run, bike, or swim? These all are good ways to exercise. When you exercise, your body uses oxygen to get energy from glucose, a six-carbon sugar. 1. How does your body feel at the start of exercise, such as a long, slow run? How do you feel 1 minute into the run; 10 minutes into the run? 2. What do you think is happening in your cells to cause the changes in how you feel? 3. Think about running as fast as you can for 100 meters. Could you keep up this pace for a much longer distance? Explain your answer.

28 Interest Grabber Answers 1. How does your body feel at the start of exercise, such as a long, slow run? How do you feel 1 minute into the run; 10 minutes into the run? Students may answer that they feel no fatigue at the start of a run; however, after 1 minute and more so after 10 minutes, they are breathing hard, their heart rate has increased significantly, and their muscles may hurt. 2. What do you think is happening in your cells to cause the changes in how you feel? Students may say that the increase in heart rate and breathing rate are a response that gets extra oxygen to the cells. The pain may be attributed to the cells becoming fatigued. 3. Think about running as fast as you can for 100 meters. Could you keep up this pace for a much longer distance? Explain your answer. Students may know that very high levels of performance can be sustained only very briefly even among the best of athletes. Students may say that the body runs out of readily available energy, food, or oxygen, or that the body builds up too many waste products in the cells.

29 Section 9-1 Chemical Pathways Glucose- C 6 H 12 O 6 Glycolysis Krebs cycle Electron transport Fermentation (without oxygen) Alcohol or lactic acid

30 Cellular Respiration the process that releases energy by breaking down glucose and other food molecules in the presence of oxygen Electrons carried in NADH Mitochondrion Glucose Glycolysis Pyruvic acid Krebs Cycle Electrons carried in NADH and FADH 2 Electron Transport Chain Cytoplasm Mitochondrion Oxygen + glucose = carbon dioxide + water + Energy

31 Glycolysis -the process in which one molecule of glucose is broken in half, producing two molecules of pyruvic acid, a 3-carbon compound Glucose 2 Pyruvic acid To the electron transport chain

32 Lactic Acid Fermentation -converts glucose into lactic acid Glucose Pyruvic acid

33 NOTEBOOK #7 1. What is cellular respiration? 2. What are the products of cellular respiration? 3. What organelle does cellular respiration take place in? 4. What is glycolysis? 5. What is glucose converted into?

34 NOTEBOOK #8 Interest Grabber Rolling and Folding Some of the steps in cellular respiration take place in the membrane inside the cell structure called the mitochondrion, which has a folded inner membrane. What purpose do these folds serve? To find out the answer to this question, perform this activity.

35 Interest Grabber Cont. 1. Obtain two sheets of paper and a metric ruler. What is the surface area of the paper? 2. Roll one sheet of paper into a tube lengthwise. What is the surface area of the rolled paper? 3. Fold the second sheet of paper into a fan. Then, roll the first sheet of paper around the folded paper so it is inside the rolled paper. What has happened to the surface area of the inside of the rolled paper? 4. What would be the value of increasing the surface area of the membrane inside a mitochondrion?

36 Interest Grabber Answers 1. Obtain two sheets of paper and a metric ruler. What is the surface area of the paper? The area will vary depending on the size of paper used. A sheet of notebook paper has an area of approximately 600 cm Roll one sheet of paper into a tube lengthwise. What is the surface area of the rolled paper? The surface area is the same as the original sheet of paper. 3. Fold the second sheet of paper into a fan. Then, roll the first sheet of paper around the folded paper so it is inside the rolled paper. What has happened to the surface area of the inside of the rolled paper? The surface area has increased (surface area of rolled paper + surface area of folded paper). 4. What would be the value of increasing the surface area of the membrane inside a mitochondrion? Increasing the surface area increases the amount of space where chemical reactions can take place.

37 Cellular Respiration process that releases energy by breaking down glucose and other food molecules in the presence of oxygen Glucose (C 6 H ) + Oxygen (0 2 ) Glycolysis Krebs Cycle Electron Transport Chain Carbon Dioxide (CO 2 ) + Water (H 2 O)

38 The Krebs Cycle pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions

39 Electron Transport Chain uses Section the 9-2 high-energy electrons from the Krebs Cycle to convert ADP into ATP Electron Transport Hydrogen Ion Movement Channel Mitochondrion Intermembrane Space ATP synthase Inner Membrane Matrix ATP Production

40 Cellular Respiration- Net Yield

41 Glycolysis- Net Yield

42 Krebs Cycle: Net Yield

43 Electron Transport Chain :Net Yield

44 NOTEBOOK #9 1. What is the Krebs Cycle? 2. What is the electron transport chain? 3. What is the net yield of ATP at the end of Cellular Respiration?