Glycolysis and Gluconeogenesis: Interactive Learning Quizzes

Question 1

In glycolysis, which enzyme catalyzes the irreversible step that initiates the pathway?

Accepted Answer

Hexokinase

Answer

Phosphofructokinase-1

Answer

Glyceraldehyde-3-phosphate dehydrogenase

Answer

Pyruvate kinase

Question 2

Which metabolite serves as the critical intermediate directly connecting glycolysis and gluconeogenesis, enabling the conversion between glucose and glucose-6-phosphate?

Accepted Answer

Glucose-6-phosphate

Answer

Glucose

Answer

Pyruvate

Answer

Acetyl-CoA

Question 3

Which enzyme, by catalyzing an irreversible reaction, commits glucose to the glycolysis pathway?

Accepted Answer

Phosphofructokinase

Answer

Hexokinase

Answer

Aldolase

Answer

Pyruvate kinase

Question 4

Which hormone stimulates gluconeogenesis, the synthesis of glucose from non-carbohydrate sources?

Accepted Answer

Glucagon

Answer

Insulin

Answer

Cortisol

Answer

Epinephrine

Question 5

What is the primary function of NADH in glycolysis?

Accepted Answer

Electron carrier

Answer

Energy carrier

Answer

Coenzyme for dehydration reactions

Answer

Substrate for ATP synthesis

Question 6

Which of the following reactions is NOT a step in gluconeogenesis?

Accepted Answer

Conversion of fructose-1,6-bisphosphate to fructose-6-phosphate

Answer

Conversion of pyruvate to oxaloacetate

Answer

Conversion of oxaloacetate to phosphoenolpyruvate

Answer

Conversion of glucose-6-phosphate to glucose

Question 7

What is the main purpose of gluconeogenesis?

Accepted Answer

Production of glucose for cellular use

Answer

Generation of energy

Answer

Synthesis of amino acids

Answer

Breakdown of fatty acids

Question 8

When oxygen is present, what metabolic pathway does pyruvate, the final product of glycolysis, primarily enter?

Accepted Answer

Citric acid cycle

Answer

Lactic acid fermentation

Answer

Alcoholic fermentation

Answer

Gluconeogenesis

Question 9

Which of the following enzymes catalyzes the irreversible step in glycolysis, committing glucose to the pathway and acting as a key regulatory point?

Accepted Answer

Phosphofructokinase-1

Answer

Hexokinase

Answer

Glyceraldehyde-3-phosphate dehydrogenase

Answer

Pyruvate kinase

Question 10

In glycolysis, which enzyme catalyzes the irreversible step that commits glucose to the pathway?

Accepted Answer

Phosphofructokinase-1 (PFK-1)

Answer

Glucokinase

Answer

Glyceraldehyde-3-phosphate dehydrogenase

Answer

Pyruvate kinase

Question 11

Identify the substance that initiates glycolysis:

Accepted Answer

Glucose

Answer

Acetyl-CoA

Answer

Lactate

Answer

Pyruvate

Question 12

During glycolysis, how many net ATP molecules are generated per glucose molecule?

Accepted Answer

Two (2)

Answer

None (0)

Answer

Six (6)

Answer

Four (4)

Question 13

What is the primary purpose of gluconeogenesis?

Accepted Answer

To synthesize glucose when glucose levels are low

Answer

To convert glycogen into glucose

Answer

To decompose pyruvate into lactate

Answer

To generate energy in the form of ATP

Question 14

Which enzyme plays a critical role in the irreversible step of gluconeogenesis, converting glucose-6-phosphate to glucose?

Accepted Answer

Glucose-6-phosphatase

Answer

Glycogen synthase

Answer

Fructose-1,6-bisphosphatase

Answer

Phosphofructokinase-1

Question 15

Among the following substances, which one is NOT a precursor that can be used in gluconeogenesis?

Accepted Answer

Palmitic acid

Answer

Alanine

Answer

Lactate

Answer

Glycerol

Question 16

What is the fundamental difference between glycolysis and gluconeogenesis?

Accepted Answer

Glycolysis is a catabolic pathway, breaking down glucose to generate energy, while gluconeogenesis is an anabolic pathway, synthesizing glucose from non-carbohydrate sources.

Answer

Glycolysis occurs in the mitochondria, whereas gluconeogenesis occurs in the nucleus.

Answer

Glycolysis consumes ATP, and gluconeogenesis generates ATP.

Question 17

Which of the following represents the balanced chemical equation summarizing glycolysis?

Accepted Answer

Glucose + 2 NAD+ + 2 ADP + 2 Pi → 2 Pyruvate + 2 NADH + 2 H+ + 2 ATP

Answer

Glucose + 1 NAD+ → Pyruvate + 1 NADH + 1 H+

Answer

2 Pyruvate + 2 NADH + 2 H+ → Glucose + 2 NAD+ + 2 ADP + 2 Pi

Question 18

Which of the following statements accurately describes the regulation of glycolysis?

Accepted Answer

Phosphofructokinase-1 is a key regulatory enzyme that is inhibited by high levels of ATP, thereby controlling the rate of glycolysis.

Answer

Glycolysis is not subject to hormonal regulation.

Answer

Glycolysis is solely regulated at the post-translational level.

Question 19

Which enzyme catalyzes the phosphorylation of glucose, the first committed step in glycolysis?

Accepted Answer

Hexokinase

Answer

Phosphofructokinase-1

Answer

Pyruvate kinase

Answer

Glyceraldehyde-3-phosphate dehydrogenase

Question 20

Which enzyme in glycolysis is a key regulatory point, sensitive to cellular energy levels and hormone signaling?

Accepted Answer

Phosphofructokinase-1

Answer

Pyruvate kinase

Answer

Glucose-6-phosphate isomerase

Answer

Hexokinase

Question 21

What is the primary precursor molecule for gluconeogenesis, the process of glucose synthesis?

Accepted Answer

Pyruvate

Answer

Acetyl-CoA

Answer

Fructose-6-phosphate

Answer

Glycerol

Question 22

Which enzyme in gluconeogenesis catalyzes the irreversible conversion of pyruvate to phosphoenolpyruvate, a key step in the pathway?

Accepted Answer

Phosphoenolpyruvate carboxykinase (PEPCK)

Answer

Fructose-1,6-bisphosphatase

Answer

Pyruvate kinase

Answer

Pyruvate dehydrogenase

Question 23

Which of the following is NOT a precursor molecule that can be converted into glucose via gluconeogenesis?

Accepted Answer

Acetyl-CoA

Answer

Lactate

Answer

Amino acids

Answer

Glycerol

Question 24

Which hormone plays a primary role in stimulating gluconeogenesis, promoting the breakdown of glycogen and the synthesis of glucose?

Accepted Answer

Glucagon

Answer

Insulin

Answer

Epinephrine

Answer

Cortisol

Question 25

In anaerobic glycolysis, which molecule accumulates as a byproduct due to the absence of oxygen?

Accepted Answer

Lactate

Answer

Pyruvate

Answer

Acetyl-CoA

Answer

Carbon dioxide

Question 26

What is the final product of glycolysis, which can be further metabolized in cellular respiration or fermentation pathways?

Accepted Answer

Pyruvate

Answer

Glucose-6-phosphate

Answer

Acetyl-CoA

Answer

Citrate