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1. Introduction to Anatomy & Physiology5h 43m
2. Cell Chemistry & Cell Components12h 36m
3. Energy & Cell Processes10h 6m
4. Tissues & Histology10h 3m
5. Integumentary System2h 20m
6. Bones & Skeletal Tissue2h 16m
7. The Skeletal System2h 35m
8. Joints2h 17m
9. Muscle Tissue2h 33m
10. Muscles1h 11m
11. Nervous Tissue and Nervous System1h 35m
12. The Central Nervous System1h 6m
- Introduction to the Central Nervous System
  18m
- The Cerebrum
  48m
13. The Peripheral Nervous System1h 26m
14. The Autonomic Nervous System1h 38m
15. The Special Senses2h 41m
16. The Endocrine System2h 48m
17. The Blood3h 22m
18. The Heart3h 42m
19. The Blood Vessels3h 35m
20. The Lymphatic System3h 16m
21. The Immune System14h 37m
22. The Respiratory System3h 20m
23. The Digestive System2h 5m
24. Metabolism and Nutrition4h 0m
25. The Urinary System2h 39m
26. Fluid and Electrolyte Balance, Acid Base Balance37m
27. The Reproductive System2h 5m
28. Human Development1h 21m
29. Heredity3h 32m

3. Energy & Cell Processes

Krebs Cycle

Anatomy & Physiology

3. Energy & Cell Processes

Krebs Cycle

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Multiple Choice

During the Krebs Cycle, what happens to all of the carbon atoms from the acetyl-CoA molecules?

They are released as carbon dioxide.

They are converted into glucose.

They are stored as glycogen.

They are incorporated into ATP molecules.

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Verified step by step guidance

Understand that the Krebs Cycle, also known as the Citric Acid Cycle, is a series of chemical reactions used by all aerobic organisms to release stored energy through the oxidation of acetyl-CoA.

Recognize that acetyl-CoA is a two-carbon molecule that enters the Krebs Cycle, where it combines with a four-carbon molecule, oxaloacetate, to form a six-carbon molecule, citrate.

Follow the cycle as citrate undergoes a series of transformations, during which two carbon atoms are released as carbon dioxide (CO2) in two separate decarboxylation reactions.

Note that these decarboxylation reactions are crucial for the release of carbon atoms from acetyl-CoA as CO2, which is then expelled from the cell as a waste product.

Conclude that the carbon atoms from acetyl-CoA do not become part of glucose, glycogen, or ATP, but are instead released as carbon dioxide during the Krebs Cycle.