Carbohydrate Metabolism Quizzes: Test Your Understanding

Question 1

What is the main function of the pentose phosphate pathway?

Accepted Answer

Generation of NADPH and ribose-5-phosphate

Answer

Breakdown of glucose

Answer

Synthesis of fatty acids

Answer

Production of ATP

Question 2

Which enzyme deficiency is associated with classic galactosemia?

Accepted Answer

Galactose-1-phosphate uridyltransferase

Answer

Galactokinase

Answer

Glucose-6-phosphate isomerase

Answer

Glucokinase

Question 3

Which molecule is a key regulator of gluconeogenesis?

Accepted Answer

Fructose-2,6-bisphosphate

Answer

Acetyl-CoA

Answer

Insulin

Answer

Epinephrine

Question 4

Which clinical feature is a hallmark of Pompe disease, a glycogen storage disorder?

Accepted Answer

Hepatosplenomegaly

Answer

Lactic acidosis

Answer

Hypoglycemia

Answer

Hyperuricemia

Question 5

Which of the following is NOT a product of glycolysis?

Accepted Answer

FADH₂

Answer

Pyruvate

Answer

ATP

Answer

NADH

Question 6

What is the primary purpose of gluconeogenesis?

Accepted Answer

To generate glucose from pyruvate

Answer

To break down glucose into pyruvate

Answer

To store glucose as glycogen

Answer

To regulate blood sugar levels

Question 7

Which enzyme catalyzes the rate-limiting step of glycolysis?

Accepted Answer

Phosphofructokinase-1

Answer

Hexokinase

Answer

Glyceraldehyde-3-phosphate dehydrogenase

Answer

Pyruvate kinase

Question 8

What is the primary function of the pentose phosphate pathway?

Accepted Answer

Generating NADPH for lipid synthesis and antioxidant defense

Answer

Generating ATP for energy production

Answer

Breaking down glucose for cellular respiration

Answer

Synthesizing nucleic acids

Question 9

What is the primary role of insulin in carbohydrate metabolism?

Accepted Answer

Promotes glucose uptake by cells and inhibits glycogenolysis

Answer

Inhibits glycolysis and stimulates gluconeogenesis

Answer

Stimulates glycogenolysis and inhibits glycolysis

Answer

Increases the rate of the pentose phosphate pathway

Question 10

Which enzyme catalyzes the conversion of glucose-6-phosphate to fructose-6-phosphate in glycolysis?

Accepted Answer

Glucose-6-phosphate isomerase

Answer

Phosphofructokinase

Answer

Hexokinase

Answer

Phosphoglucomutase

Question 11

Which enzyme is the key regulatory enzyme in gluconeogenesis, the synthesis of glucose from non-carbohydrate precursors?

Accepted Answer

PEP carboxykinase

Answer

Pyruvate kinase

Answer

Glucose-6-phosphatase

Answer

Hexokinase

Question 12

Which pathway generates ribose-5-phosphate, a precursor for nucleotide synthesis?

Accepted Answer

Pentose phosphate pathway

Answer

Glycolysis

Answer

Gluconeogenesis

Answer

Krebs cycle

Question 13

What is the primary end product of anaerobic glycolysis?

Accepted Answer

Lactate

Answer

Glucose-6-phosphate

Answer

Pyruvate

Answer

Acetyl-CoA

Question 14

Which enzyme catalyzes the breakdown of starch into glucose?

Accepted Answer

Amylase

Answer

Protease

Answer

Lipase

Answer

Glucokinase

Question 15

In glycolysis, NADH is produced. How does this contribute to the overall energy yield of the pathway?

Accepted Answer

NADH is used to generate ATP through oxidative phosphorylation.

Answer

NADH provides electrons for the conversion of pyruvate to lactate.

Question 16

Which hormone stimulates the breakdown of glycogen into glucose?

Accepted Answer

Glucagon

Answer

Epinephrine

Answer

Insulin

Answer

ACTH

Question 17

The pentose phosphate pathway primarily generates:

Accepted Answer

NADPH and pentose sugars

Answer

ATP and NADH

Answer

Coenzyme A and heme

Answer

FADH2 and acetyl-CoA

Question 18

What is the end product of glycolysis?

Accepted Answer

Pyruvate

Answer

Lactate

Answer

Glucose-6-phosphate

Answer

Acetyl-CoA

Question 19

Glycogen synthesis is stimulated by:

Accepted Answer

Insulin

Answer

Epinephrine

Answer

Glucagon

Answer

Cortisol

Question 20

Which of the following is a pathological condition characterized by impaired glucose oxidation?

Accepted Answer

Diabetes mellitus

Answer

Anemia

Answer

Cirrhosis

Question 21

What is the primary function of glycogenolysis?

Accepted Answer

To release glucose into the bloodstream

Answer

To store glucose as glycogen

Answer

To synthesize amino acids

Answer

To generate ATP

Question 22

Which of the following is NOT a step in glycolysis?

Accepted Answer

Citric acid cycle

Answer

Hexokinase reaction

Answer

Phosphofructokinase reaction

Answer

Pyruvate kinase reaction

Question 23

The pentose phosphate pathway primarily generates:

Accepted Answer

NADPH

Answer

FADH2

Answer

Acetyl-CoA

Answer

ATP

Question 24

Which enzyme catalyzes the rate-limiting step in glycolysis?

Accepted Answer

Phosphofructokinase

Answer

Hexokinase

Answer

Glyceraldehyde-3-phosphate dehydrogenase

Answer

Pyruvate kinase

Question 25

The end product of glycolysis under anaerobic conditions is:

Accepted Answer

Lactate

Answer

Acetyl-CoA

Answer

Ethanol

Answer

Pyruvate

Question 26

A characteristic feature of glycogen is its:

Accepted Answer

Highly branched structure

Answer

Linear structure

Answer

Storage in the nucleus

Answer

Solubility in lipids

Question 27

The primary function of the pentose phosphate pathway is to provide:

Accepted Answer

Ribose-5-phosphate for nucleotide synthesis

Answer

ATP for cellular energy

Answer

Acetyl-CoA for fatty acid synthesis

Answer

NADH for mitochondrial respiration