Q: Which of the following statements about lactic acid fermentation in human muscle cells is correct?

It regenerates NAD\textsuperscript{+} so glycolysis can continue in the absence of oxygen.

Q: A patient with a rare genetic disorder cannot convert pyruvate to lactate. What is the most likely consequence during intense exercise?

Glycolysis would slow down due to a lack of NAD\textsuperscript{+} regeneration.

Q: A baker is using yeast to make bread. Which of the following best explains why the dough rises?

CO\textsubscript{2} is produced during alcoholic fermentation, causing bubbles in the dough.

Q: If a cell is placed in an environment lacking oxygen, which of the following will most likely occur?

The cell will rely on fermentation to regenerate NAD\textsuperscript{+} for glycolysis.

Question 1

Which of the following best describes the net products of glycolysis from one molecule of glucose?

Accepted Answer

2 ATP, 2 NADH, and 2 pyruvate

Question 2

During glycolysis, which enzyme is responsible for the phosphorylation of glucose to glucose-6-phosphate?

Accepted Answer

Hexokinase

Question 3

Which of the following statements about lactic acid fermentation in human muscle cells is correct?

Accepted Answer

It regenerates NAD	extsuperscript{+} so glycolysis can continue in the absence of oxygen.

Question 4

A patient with a rare genetic disorder cannot convert pyruvate to lactate. What is the most likely consequence during intense exercise?

Accepted Answer

Glycolysis would slow down due to a lack of NAD	extsuperscript{+} regeneration.

Question 5

Which of the following equations correctly represents the overall reaction of glycolysis?

Accepted Answer

$$\mathrm{C_6H_{12}O_6$} + 2\ \mathrm{NAD^+} + 2\ \mathrm{ADP} + 2\ \mathrm{P_i} \rightarrow 2\ \mathrm{C_3H_4O_3} + 2\ \mathrm{NADH} + 2\ \mathrm{ATP} + 2\ \mathrm{H_2O}$$

Question 6

Which step in glycolysis is considered the key regulatory step and is catalyzed by an enzyme that is allosterically inhibited by ATP and citrate?

Accepted Answer

Phosphofructokinase catalyzing the conversion of fructose-6-phosphate to fructose-1,6-bisphosphate

Question 7

Obligate anaerobes, such as Clostridium botulinum, are unable to survive in the presence of oxygen because:

Accepted Answer

They lack enzymes to detoxify reactive oxygen species.

Question 8

In alcoholic fermentation, which of the following is the correct sequence of events starting from pyruvate?

Accepted Answer

Pyruvate is converted to acetaldehyde, which is then reduced to ethanol.

Question 9

A baker is using yeast to make bread. Which of the following best explains why the dough rises?

Accepted Answer

CO	extsubscript{2} is produced during alcoholic fermentation, causing bubbles in the dough.

Question 10

Which of the following best explains why glycolysis can occur in both aerobic and anaerobic conditions?

Accepted Answer

It does not require oxygen and occurs in the cytoplasm.

Question 11

A marathon runner experiences muscle fatigue and soreness after a race. Which metabolic process is most directly responsible for the accumulation of lactic acid in the muscles?

Accepted Answer

Lactic acid fermentation

Question 12

Which of the following is a major difference between fermentation and aerobic respiration?

Accepted Answer

Fermentation does not use an electron transport chain, while aerobic respiration does.

Question 13

If a cell is placed in an environment lacking oxygen, which of the following will most likely occur?

Accepted Answer

The cell will rely on fermentation to regenerate NAD	extsuperscript{+} for glycolysis.

Question 14

Which of the following best explains why phosphofructokinase is considered the 'pacemaker' of glycolysis?

Accepted Answer

It is the main regulatory enzyme, responding to cellular energy levels by being inhibited by ATP and citrate.

Question 15

Which of the following is a correct statement about the fate of lactate produced in human muscles during intense exercise?

Accepted Answer

Lactate is transported to the liver, where it can be converted back to glucose.

Question 16

Which of the following best describes the role of NAD	extsuperscript{+} in glycolysis?

Accepted Answer

It acts as an electron acceptor, becoming reduced to NADH.

Question 17

A mutation in yeast prevents the conversion of acetaldehyde to ethanol. What would be the most immediate effect on glycolysis?

Accepted Answer

NAD	extsuperscript{+} would not be regenerated, causing glycolysis to slow or stop.

Question 18

Which of the following is a real-world application of lactic acid fermentation?

Accepted Answer

Production of yogurt from milk by bacteria

Question 19

Which of the following best explains why ATP is required in the initial steps of glycolysis?

Accepted Answer

ATP provides activation energy to phosphorylate glucose and its intermediates.

Lecture 13 - Cellular Respiration and Fermentation: Glycolysis and Anaerobic Pathways

Guida di studio - Domande di pratica

Study guide - Flashcard