1.
In which phase of cellular respiration is water made?
Correct Answer
D. Electron Transport Chain
Explanation
The correct answer is Electron Transport Chain. During the Electron Transport Chain phase of cellular respiration, water is made as a byproduct. This process occurs in the inner mitochondrial membrane, where electrons from NADH and FADH2 are transported along a series of protein complexes. As the electrons move through the chain, they combine with oxygen molecules and protons to form water. This final step of cellular respiration produces water and generates ATP, the energy currency of the cell.
2.
In which phase of cellular respiration is oxygen a substrate?
Correct Answer
C. Electron Transport Chain
Explanation
In the electron transport chain phase of cellular respiration, oxygen acts as a substrate. This is because oxygen is the final electron acceptor in the chain, receiving the electrons from the electron carriers and combining with hydrogen ions to form water. This process generates a large amount of ATP, the energy currency of the cell. Therefore, oxygen is essential for the electron transport chain to occur and for the efficient production of energy in the form of ATP.
3.
In which phase of cellular respiration is glucose a substrate?
Correct Answer
A. Glycolysis Cycle
Explanation
Glucose is a substrate in the Glycolysis Cycle. Glycolysis is the first step in cellular respiration, where glucose is broken down into pyruvate molecules. This process occurs in the cytoplasm of the cell and does not require oxygen. The pyruvate molecules produced in glycolysis then enter the Krebs Cycle, where further breakdown occurs to release more energy. Therefore, glucose acts as a substrate in the initial step of cellular respiration, which is the Glycolysis Cycle.
4.
On average, how many ATP (adenosine Triphosphate) can be made from each NADH during the Electron Transport Chain process?
Correct Answer
C. 3
Explanation
During the Electron Transport Chain process, each NADH molecule can produce 3 ATP molecules. This is because NADH donates its electrons to the electron transport chain, which creates a proton gradient across the inner mitochondrial membrane. This proton gradient is then used by ATP synthase to produce ATP. Each NADH molecule can transfer enough electrons to the electron transport chain to create a proton gradient that generates 3 ATP molecules.
5.
On average, how many ATP (adenosine Triphosphate) can be made from each FADH2 during the Electron Transport Chain process?
Correct Answer
B. 2
Explanation
During the Electron Transport Chain process, each FADH2 molecule can generate 2 ATP molecules. This is because FADH2 transfers its electrons to Complex II of the Electron Transport Chain, which results in the pumping of 2 protons across the inner mitochondrial membrane. These protons then flow back through ATP synthase, generating 2 ATP molecules. Therefore, the correct answer is 2.
6.
If the enzyme for one step of cellular respiration were missing or defective. The process would continue producing ATP at a lower number than 38.
Correct Answer
B. False
Explanation
If the enzyme for one step of cellular respiration were missing or defective, it would disrupt the entire process of cellular respiration. Each step of cellular respiration relies on specific enzymes to catalyze the reactions and convert substrates into products. If one enzyme is missing or defective, it would halt the progression of cellular respiration, leading to a complete loss of ATP production. Therefore, the statement that the process would continue producing ATP at a lower number than 38 is incorrect.
7.
What happens to the high-energy electrons (Hydrogen) held by NADH, if there is no Oxygen?
Correct Answer
A. Pyruvic acid takes back electrons
Explanation
If there is no oxygen available, the high-energy electrons held by NADH cannot be transferred to the electron transport chain for further energy production. In this case, pyruvic acid takes back the electrons from NADH in order to regenerate NAD+ and continue the process of glycolysis. This allows glycolysis to continue producing a small amount of ATP through substrate-level phosphorylation, even in the absence of oxygen.
8.
How many carbon atoms are present in Phosphoenol Pyruvic acid? (Please enter a number from 0 to 20.)
Correct Answer
3
Explanation
Phosphoenol Pyruvic acid is a molecule that consists of three carbon atoms. Therefore, the correct answer is 3.
9.
Glucose 6 Phosphate and Fructose 6 Phosphate are identical molecules.
Correct Answer
B. False
Explanation
Glucose 6 phosphate and fructose 6 phosphate are not identical molecules. While they both contain a phosphate group, they differ in their sugar structure. Glucose 6 phosphate is derived from glucose, whereas fructose 6 phosphate is derived from fructose. Therefore, they have different molecular structures and are not identical molecules.
10.
How many molecules of Carbon Dioxide are produced every turn of the Kreb's Cycle? (Please enter a number from 0 to 25).
Correct Answer
3
Explanation
In each turn of the Kreb's Cycle, three molecules of Carbon Dioxide are produced.