The Molecule Quiz

1. What is the cause of the cramps you feel in your muscles during strenuous exercise?

Lactic acid fermentation

Alcohol fermentation

Chemiosmosis coupling

Too much oxygen delivery to the muscles

Oxidative phosphorylation

During strenuous exercise, the muscles require a lot of energy, which is produced through cellular respiration. However, when the oxygen supply to the muscles is insufficient, the cells switch to anaerobic respiration, specifically lactic acid fermentation. This process produces lactic acid as a byproduct, which can build up in the muscles and cause cramps. Therefore, lactic acid fermentation is the cause of the cramps felt during strenuous exercise.

Explanation

During strenuous exercise, the muscles require a lot of energy, which is produced through cellular respiration. However, when the oxygen supply to the muscles is insufficient, the cells switch to anaerobic respiration, specifically lactic acid fermentation. This process produces lactic acid as a byproduct, which can build up in the muscles and cause cramps. Therefore, lactic acid fermentation is the cause of the cramps felt during strenuous exercise.

2. Which of the following statements is incorrect?

Glycolysis can occur with or without oxygen

Glycolysis occurs in the mitochondria

Glycolysis is the first step of both anaerobic and aerobic respiration

Glycolysis leads to the production of 2 ATP, 2 NADH, and 2 pyruvate

not-available-via-ai

Explanation

not-available-via-ai

3. Which of the following procedures occurs in both respiration and photosynthesis?

Calvin cycle

Chemiosmosis

Citric acid cycle

Krebs cycle

Glycolysis

Chemiosmosis is the process that occurs in both respiration and photosynthesis. It involves the movement of ions across a membrane, which generates ATP, the energy currency of the cell. In respiration, chemiosmosis occurs in the inner mitochondrial membrane, while in photosynthesis, it occurs in the thylakoid membrane of chloroplasts. This process is essential for the production of ATP in both cellular respiration and photosynthesis, making it the correct answer.

Explanation

Chemiosmosis is the process that occurs in both respiration and photosynthesis. It involves the movement of ions across a membrane, which generates ATP, the energy currency of the cell. In respiration, chemiosmosis occurs in the inner mitochondrial membrane, while in photosynthesis, it occurs in the thylakoid membrane of chloroplasts. This process is essential for the production of ATP in both cellular respiration and photosynthesis, making it the correct answer.

4. Most of the ATP creation during respiration occurs as a result of what driving force?

Electrons moving down a concentration gradient

Electrons moving down the electron transport chain

Protons moving down a concentration gradient

Sodium ions moving down a concentration gradient

Movement of pyruvate from the cytoplasm into the mitochondria

During respiration, ATP is created through a process called oxidative phosphorylation. This process involves the movement of protons (H+) down a concentration gradient across the inner mitochondrial membrane. As electrons pass through the electron transport chain, protons are pumped from the mitochondrial matrix to the intermembrane space, creating a concentration gradient. The movement of protons back into the matrix through ATP synthase drives the synthesis of ATP. Therefore, the correct answer is "Protons moving down a concentration gradient."

Explanation

During respiration, ATP is created through a process called oxidative phosphorylation. This process involves the movement of protons (H+) down a concentration gradient across the inner mitochondrial membrane. As electrons pass through the electron transport chain, protons are pumped from the mitochondrial matrix to the intermembrane space, creating a concentration gradient. The movement of protons back into the matrix through ATP synthase drives the synthesis of ATP. Therefore, the correct answer is "Protons moving down a concentration gradient."

5. Which of the following molecules can give rise to the most ATP?

NADH

FADH2

Pyruvate

Glucose

Glucose can give rise to the most ATP because it is the starting molecule for cellular respiration, a process that generates ATP. Glucose is broken down through glycolysis, the Krebs cycle, and oxidative phosphorylation, which produce a total of 36-38 ATP molecules per glucose molecule. On the other hand, NADH and FADH2 are electron carriers that donate electrons to the electron transport chain, generating a smaller amount of ATP. Pyruvate is an end product of glycolysis and can be further metabolized to produce ATP, but it yields less ATP compared to glucose.

Explanation

Glucose can give rise to the most ATP because it is the starting molecule for cellular respiration, a process that generates ATP. Glucose is broken down through glycolysis, the Krebs cycle, and oxidative phosphorylation, which produce a total of 36-38 ATP molecules per glucose molecule. On the other hand, NADH and FADH2 are electron carriers that donate electrons to the electron transport chain, generating a smaller amount of ATP. Pyruvate is an end product of glycolysis and can be further metabolized to produce ATP, but it yields less ATP compared to glucose.

6. Which of the following is a proper representation of the products of a single glucose molecule after it has completed the Krebs cycle?

10 ATP, 4 NADH, 2 FADH2

10 NADH, 4 FADH2, 2 ATP

10 ATP, 4 FADH2, 2 NADH

10 NADH, 4 ATP, 2 FADH2

10 NADH, 4 FADH2, 2 ATP

not-available-via-ai

Explanation

not-available-via-ai

7. Match the following

This process includes the reactions that use NADH and FADH2 to produceOxidative Phosphorylation

This reaction occurs in the matrix of the mitochondria and includes FADH2 among its products

This process uses the proton gradient created by the movement of electrons to form ATP

This reaction is performed to recycle NAD+ needed for efficient respiration

This reaction produces 2 molecules of pyruvate

Submit