Cellular Respiration Workbooklet

Adenosine triphosphate (ATP) is the energy molecule used by all cells to do work. It is a nucleotide consisting of a nitrogen-containing base (adenine, thymine, cytosine, or guanine), a 5-carbon sugar, and 3 phosphate groups. ATP is able to store and transport chemical energy within cells. The LAST TWO phosphate groups (PO4), are joined by HIGH-ENERGY bonds. When these bonds are broken, energy is released for cells to use and ADP forms. Enzymes help to break and reform these high-energy bonds.

1. What does ATP stand for?

2. What three main things make up an ATP molecule?

3. How many high-energy bonds does ATP contain?

4. Where are these high-energy bonds found in ATP?

5. What helps weaken these bonds so energy can be released and then later help reform them?

6. When ATP loses a phosphate group __________ is released for cells and a molecule of _________ forms.

Mitochondria are the powerhouses of the cell because they “burn” or break the chemical bonds of glucose to release energy to do work in a cell. Remember that this energy originally came from the sun and was stored in chemical bonds by plants during photosynthesis. Glucose and other carbohydrates made by plants during photosynthesis are broken down by the process of aerobic cellular respiration (requires oxygen) in the mitochondria of the cell. This releases energy (ATP) for the cell. The more active a cell (such as a muscle cell), the more mitochondria it will have. The mitochondria are about the size of a bacterial cell and are often peanut-shaped. Mitochondria have their own DNA and a double membrane like the nucleus and chloroplast. The outer membrane is smooth, while the inner membrane is convoluted into folds called cristae in order to increase the surface area.

7. Why are mitochondria called the powerhouse of the cell?

8. What cell process occurs in the mitochondria?

9. Why do some cells have MORE mitochondria? Give an example.

10. What simple sugar is broken down in the mitochondria?

11. Where does the energy in glucose come from ORIGINALLY?

12. Where is this energy stored in glucose?

13. Why is cellular respiration an aerobic process?

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14. What energy is released when the chemical bonds of glucose are broken?

15. Name two other organelles besides the mitochondria that contain DNA and have a double membrane.

16. Describe the outer membrane of the mitochondria.

17. Why is the inner mitochondrial membrane folded?

18. What are the folds called?

Overview of Aerobic RespirationWhat is the overall equation of aerobic respiration? Name the four stages of aerobic respiration and identify where they occur within the cell:Stage 1:Stage 2:Stage 3:Stage 4:

Additional Key Words:Inner membraneMatrix

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Pyruvate oxidation results in three changes to pyruvate:1.

2.

Cytoplasm

Stage 1 – Glycolysis

Label the Diagram

● Pyruvate

● ADP

● ATP

● Glucose

● NAD+

● NADH

Stage 2 – Pyruvic Acid Oxidation

Label the diagram choosing from the following words or phrases: • Acetyl CoA (acetyl coenzyme A)

• Pyruvic acid

• NADH + H+

• Coenzyme A

• CO2

• NAD+

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Questions

1. What are the characteristics of glucose that make it well suited as an energy supply molecule within our bodies? 2. The conversion of glucose energy to ATP energy is less than 50% efficient. In what way to birds and mammals take advantage of this inefficiency? 3. Briefly describe one cellular process that involves the use of active transport. How is ATP involved in this process? 4. Why is cellular respiration necessary?5. What are the four stages of aerobic respiration?6. Explain the difference between oxic and anoxic conditions.7. Describe how aerobic cellular respiration is different from anaerobic respiration. 8. State where glycolysis occurs in a cell and whether or not oxygen is required.9. Name three products that result from glycolysis.

Simplistic View of Kreb’s CycleLabel the diagram choosing from the following words or phrases:CoANADHATPFADH2

The diagram is a simplified view of stage 2 and stage 3 of aerobic respiration.

1. Circle the part of the diagram that shows pyruvate oxidation.

2. What happens to the carbon atoms in acetyl CoA?

3. Identify the product(s) of the Krebs cycle that provides energy for cell processes. How many molecules of this(these) are produced for every turn of the Krebs cycle?

4. Identify the product(s) that provides reducing energy for cell processes. How many molecules of this(these) are produced for every turn of the Krebs cycle?

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Directions. Fill in the missing labels in this outline of the mitochondrial ECT and then complete the blanks.

The NADH carries the

electrons gained from food to the _________________________.

As these electrons are passed along carrier molecules, the energy released is used to pump

_______________________________across the membrane.

The electrons are finally accepted by _______________molecules.

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______________________ is the byproduct of the electron transport chain.

Fill in the missing labels in this outline of chemiosmosis. One molecule of ATP is synthesized from ____________ and ____________as an H+ ion passes through _________________________ into the mitochondrial matrix from the H+ reservoir in the intermembrane space.

THEORETICAL ATP YIELD FROM AEROBIC RESPIRATIONFill in the missing labels in this outline of chemiosmosisIn the empty boxes on the diagram, fill in the numbers of molecules produced from one glucose molecule at each step of aerobic cellular respiration.

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