Carbohydrate Metabolism

Flashcards covering key concepts from carbohydrate metabolism, including digestion, glycolysis, gluconeogenesis, and hormonal regulation.

What is the first stage in carbohydrate catabolism?

Digestion, which is the breakdown of food into small molecules.

Where does carbohydrate digestion begin in the body?

In the mouth.

What enzyme is responsible for carbohydrate digestion in the mouth?

Salivary α-amylase.

What are the major end products of carbohydrate digestion?

Monosaccharides.

What cellular process ensues when glucose enters a cell?

It is converted to glucose 6-phosphate.

Why is glucose 6-phosphate important for glucose metabolism?

It traps glucose within the cell and is an allosteric inhibitor for hexokinase.

What metabolic pathway converts glucose to pyruvate?

Glycolysis.

What is the net yield of ATP from glycolysis per glucose molecule?

Two ATP molecules.

What happens to pyruvate under aerobic conditions?

It is converted to acetyl-CoA.

What process yields lactate from pyruvate?

Anaerobic reduction of pyruvate.

What is glycogenesis?

The synthesis of glycogen from glucose.

What hormone is secreted when blood glucose levels are high?

Insulin.

What is gluconeogenesis?

The synthesis of glucose from noncarbohydrate sources.

What metabolic condition leads to excessive thirst and frequent urination?

Hyperglycemia.

What is the main function of glucagon in glucose metabolism?

It stimulates the breakdown of glycogen in the liver to increase blood glucose levels.

What is the Cori cycle?

The conversion of lactate into pyruvate, from which glucose is synthesized.

What happens to glucose in the muscle cells during strenuous exercise?

It is converted to lactate.

How is energy derived from fats during prolonged periods without food?

Through beta-oxidation and the citric acid cycle.