Biol Chapter 7 Review
Which of the following is the enzyme used to synthesize ATP?
*none of these choices are correct* ATP phosphodiesterase ATP hydrolase ATP kinase Incorrect ATP phosphorylase
The initial reaction of the citric acid cycle, also called the Krebs cycle, involves the addition of a
2-carbon molecule to a 4-carbon molecule.
Carbon dioxide (CO₂) is produced during aerobic respiration. Which of the following statements is TRUE?
CO₂ is often the product when an organic molecule is oxidized.
Creation of a proton gradient by the electron transport chain represents
potential energy
Proton pumps are protein complexes that
pump protons from the interior of the cell to the exterior.
If glycolysis was blocked in yeast, which of the following would decrease in concentration?
pyruvate
Aerobic vs anaerobic metabolism Complete the sentences with the correct terms from the list.
- The term anaerobicdescribes cellular respiration in the absence of oxygen. - Oxygen is the final electron acceptor in aerobic respiration. - The breakdown of organic molecules without oxygen is called fermentation. - During fermentation, yeast break down pyruvate into CO₂ and acetaldehyde. - Aerobic respiration produces 34-38 ATP molecules whereas anaerobic respiration produces 2 ATP molecules.
A single "turn" of the citric acid cycle, also called the Krebs cycle, will yield
1 ATP, 3 NADH, and 1 FADH₂.
Arrange the electron acceptors in order from highest to lowest energy. 1 = Cytochrome c 2 = Oxygen 3 = Cytochrome c oxidase
1, 3, 2
Place these molecules in the order they appear in glycolysis (from 1-3).
1. Glucose 2. Two Molecules of glyceraldehyde 3-phosphate 3. Two molecules of pyruvate
If the protons could pass back across the membrane through the proton pump, the production of ATP would not be affected.
False
Electrons are brought to the electron transport system by the oxidation of
NADH and FADH₂.
Why is formation of ATP by ATP synthase in the mitochondria known as oxidative phosphorylation?
Oxygen is the terminal electron acceptor in the mitochondrial electron transport chain, which creates the proton gradient necessary to power ATP synthase
In the diagram above, describe the advantage of having a pathway organized as a cycle.
The final product of the cycle can be combined with a small molecule entering the cycle, making it more reactive.
Why is pyruvate converted to lactate in anaerobic conditions?
To regenerate NAD+ from NADH and keep glycolysis functioning.
The protons are generated during oxidation reactions.
True
When oxygen accepts electrons, water is produced as a byproduct.
True
Fatty acids and some amino acids are converted directly into _____________ for ATP production.
acetyl CoA
Before entering the citric acid cycle, also called the Krebs cycle, pyruvate is converted to
acetyl-CoA.
Synthesis of ATP via a proton gradient is called
chemiosmosis.
In cellular respiration, carbon dioxide is formed from the oxidation of the following:
glucose
Which of the following is the correct equation for aerobic cellular respiration?
glucose + 6 O₂ → 6 CO₂ + 6 H₂O + energy intermediates + heat
The movement of protons through ATP synthase occurs from the
intermembrane space to the matrix.
Based on the figure above, when pyruvate is converted to acetyl CoA it is ______.
oxidized
