Mitochondria and Cellular Respiration PDF

Preview

Summary

67687878u...

Description

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

Model 1 – Power Conversion from Coal to Electricity

HANDOUT 3.11.A

If you need to use your phone or computer, you don’t directly use a lump of coal to power it. However, the energy stored in the battery of your phone or computer may very well have originated from a fossil fuel, such as coal, or from hydroelectric or nuclear sources. The process of releasing the energy stored in coal and converting it into usable electricity that charges the battery on your phone or computer is complex and takes time. Only after coal has undergone many energy-harvesting steps at the electrical plant, as shown in the figure below, can the resulting electricity be used to charge your phone’s battery. Finally, the charged battery allows you to put your phone to work when you need it.

Generator

Turbine

Transformer Power line

Coal

Community

Boiler

Model 1: Power conversion from coal to electricity

Similarly, the energy stored in glucose from your diet requires a long series of complex steps to be released and converted to usable energy for our cells. Just as you can’t plug your phone into coal and make it work, your cells can’t use glucose directly to power their work. Thus, the energy in glucose is released and converted—through a process known as cellular respiration—into forms of energy that charge the cell’s “battery.” You will learn about ATP, the cell’s charged battery, from Model 2. 1. Glucose is the basic unit of stored energy for cells. How do plant cells get glucose?

2. How do animal cells get glucose?

Student Resource © 2021 College Board

101

Pre-AP Biology

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

HANDOUT 3.11.A

3. In your own words, describe how the process of cellular respiration is similar to the process of converting fossil fuels such as coal to electricity.

Check with your teacher before moving on.

Pre-AP Biology

102

Student Resource © 2021 College Board

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

Model 2 – The ATP Cycle

HANDOUT 3.11.B

The main form of energy that can be readily used by cells to do work is potential energy stored in a molecule known as adenosine triphosphate or ATP. Study the model below to learn more about ATP. ADP

ATP

P

P

P

P

P

Energy + P Adenosine diphosphate (ADP) + 1 phosphate

Energy

Partially charged battery

Adenosine triphosphate (ATP) Fully charged battery

Model 2: The ATP cycle

1. Carefully study the two molecules in the model: ADP and ATP. What is the difference between them?

2. Knowing what you know about how ATP is named, what do you think the letters in ADP stand for?

3. Think of ATP like a charged battery. If the cell uses some of the energy in this “battery,” what must happen to the ATP molecule for it to be converted to a partially charged battery (ADP + P)?

4. Energy can be stored in (and released from) chemical bonds in molecules. Draw an arrow to indicate the bond that stores energy when ATP forms from ADP +P. (This is the same bond that releases energy when ATP is converted into ADP + P.)

Student Resource © 2021 College Board

103

Pre-AP Biology

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

HANDOUT 3.11.B

5. For ADP + P to be converted to ATP, energy is needed, as shown in this model. Where does this energy come from? (Hint: Think back to Model 1.)

6. How is the production of ATP similar to how you charge a phone or other electronic device with a battery built in?

7. What questions do you have?

Check with your teacher before moving on.

Pre-AP Biology

104

Student Resource © 2021 College Board

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

Model 3 – Cellular Respiration in the Mitochondrion

HANDOUT 3.11.C

As you have learned previously, photosynthesis is a process by which some cells are able to capture energy from the sun and store it in energy-rich carbohydrate molecules such as glucose. The glucose is then stored by the plant to be used at another time, or perhaps eaten by an animal who needs that same glucose to power its own cells. To release and use the energy in glucose, cells need to first convert the energy from glucose into energy stored in ATP. All living cells, even photosynthetic cells, must be able to make the glucose-to-ATP conversion. This process of releasing the energy storedin molecules such as glucose to charge the ATP battery is known as cellular respiration. In order to simplify our learning about cellular respiration, we will focus only on eukaryotic cells. Keep in mind, however, that prokaryotes must also have the ability to convert and use energy. In fact, prokaryotes have more diverse biochemical approaches to these processes than eukaryotes do.

Glycolysis and the Krebs cycle + 2NAD

2NADH + 2H

on

+

2

Inner membrane 6H 2O

1 glucose C6H12O6

2 pyruvate C3H4O3

Electron transport 6O2

Model 3: Cellular respiration in the mitochondrion

Student Resource © 2021 College Board

105

Pre-AP Biology

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

HANDOUT 3.11.C

1. Using Model 3 as a guide, what are the reactants of cellular respiration? In other words, what molecules go into cellular respiration?

2. What are the molecular products of cellular respiration?

3. Write the full chemical equation for cellular respiration. (Hint: While the image shows cellular respiration as broken into two stages, the sum of these stages is one chemical reaction.)

4. In cellular respiration, the energy stored in glucose molecules is released and stored in what energy-rich molecule (the cell’s charged battery) that cells use to do work?

5. Once ATP is used for cellular work, it breaks into the lower-energy ADP molecule and inorganic phosphate (P). Based on Model 2 and Model 3, what does the cell do with low-energy ADP + P?

Pre-AP Biology

106

Student Resource © 2021 College Board

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

6. Through the process of cellular respiration, 36–38 ADP + P are converted to 36–38 ATP. On Model 3, write “ADP + P” and “ATP” to correctly label the models of batteries on the diagram.

HANDOUT 3.11.C

7. Write the full equation for cellular respiration, including ADP + P and ATP.

8. In your own words, describe (a) the process and (b) the function of cellular respiration.

9. List at least two variables that might influence the rate of cellular respiration.

10. CO2 is toxic to your cells, yet cells produce it through the essential process of cellular respiration. Thus, the CO2 that is produced must be removed from your cells. Considering what you know about your own body, what happens to the CO2 that your cells produce?

Student Resource © 2021 College Board

107

Pre-AP Biology

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

HANDOUT 3.11.C

11. CHALLENGE! If you weigh yourself at night and again in the morning, you will find that you lose a small amount of weight every night. This is a direct result of cellular respiration. Use your understanding of cellular respiration to explain why you lose weight at night.

12. What questions do you have?

Check with your teacher before moving on.

Pre-AP Biology

108

Student Resource © 2021 College Board

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

Model 4 – The Relationship Between Photosynthesis and Cellular Respiration in Eukaryotic Cells

Solar energy

Glucose + O2

ADP

HANDOUT 3.11.D

+P Usable energy for cells

Chloroplast

Mitochondrion

CO2+H2O ATP

Model 4: The relationship between photosynthesis and cellular respiration in eukaryotic cells

1. On the diagram, write the phrase “site of photosynthesis” next to the organelle in which photosynthesis occurs.

2. On the diagram, write the phrase “site of cellular respiration” next to the organelle in which cellular respiration occurs.

Student Resource © 2021 College Board

109

Pre-AP Biology

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

HANDOUT 3.11.D

3. What products from photosynthesis are used for cellular respiration?

4. What products of cellular respiration are used by the chloroplast during photosynthesis?

5. In the space below, write the equation for cellular respiration and the equation for photosynthesis.

6. Below, rewrite the equations and add the energy input or output to the equations.

7. What is the relationship between the equations for photosynthesis and cellular respiration?

8. Is photosynthesis the exact opposite of cellular respiration? Explain.

Pre-AP Biology

110

Student Resource © 2021 College Board

Lesson 3.11: Model-Based Guided Inquiry Activity – Comparing Cellular Respiration and Photosynthesis Unit 3: Cellular Systems

9. Circle the correct answer, and then explain your reasoning: (a) Plants / Animals / Both … have cells that can undergo photosynthesis.

HANDOUT 3.11.D

Explanation:

(b) All / Some … plant cells can photosynthesize. Explanation:

(c) Plants / Animals / Both … use cellular respiration to harvest energy from glucose to“charge” the ATP battery for cellular work. Explanation:

10. What questions do you have?

Student Resource © 2021 College Board

111

Pre-AP Biology...