[21] Metabolism Regulation

Question 1

What is metabolism regulation?

Answer 1

It is the control of metabolic pathways to maintain homeostasis in the body.

Question 2

How does the body achieve metabolism regulation?

Answer 2

1. Enzyme regulation
2. Hormonal control
3. Genetic regulation

Question 3

What is enzyme regulation in the context of metabolism?

Answer 3

It involves the control of enzyme activity, including allosteric regulation, covalent modification, and enzyme production.

Question 4

What is hormonal control in the context of metabolism?

Answer 4

It involves hormones regulating metabolic pathways. Examples include insulin and glucagon.

Question 5

What is genetic regulation in the context of metabolism?

Answer 5

It involves control at the gene level, influencing the synthesis of enzymes and other proteins involved in metabolism.

Question 6

How does insulin regulate metabolism?

Answer 6

1. Promotes glucose uptake in cells
2. Promotes glycogenesis
3. Inhibits gluconeogenesis

Question 7

How does glucagon regulate metabolism?

Answer 7

1. Stimulates gluconeogenesis
2. Stimulates glycogenolysis
3. Inhibits glycogenesis

Question 8

What is allosteric regulation in metabolic processes?

Answer 8

It’s a mechanism that changes the activity of an enzyme by binding a molecule at a site other than the active site.

Question 9

What is covalent modification in metabolic processes?

Answer 9

It involves the addition or removal of a chemical group (like a phosphate) to or from a protein, thereby affecting its function.

Question 10

What is a feedback inhibition?

Answer 10

It’s a type of regulation where the product of a metabolic pathway inhibits an enzyme involved earlier in the pathway.

Question 11

How does the body regulate metabolism during fasting?

Answer 11

In fasting, hormones like glucagon and cortisol are secreted, promoting processes such as glycogenolysis and gluconeogenesis.

Question 12

How does the body regulate metabolism during feeding?

Answer 12

In the fed state, insulin is secreted, promoting processes like glycogenesis, lipid synthesis, and protein synthesis.

Question 13

What is the role of AMP in metabolism regulation?

Answer 13

AMP acts as a signal of low energy status and activates processes to generate ATP.

Question 14

What is the role of ATP in metabolism regulation?

Answer 14

ATP acts as a signal of high energy status and inhibits processes that generate ATP while promoting those that consume ATP.

Question 15

What is the role of Acetyl-CoA in metabolism regulation?

Answer 15

Acetyl-CoA acts as a metabolic crossroads, involved in energy production (Krebs cycle), and synthesis of fatty acids and cholesterol.

Question 16

What is the role of NADH and FADH2 in metabolism regulation?

Answer 16

They are electron carriers and their levels indicate the energy state of the cell, affecting processes like glycolysis, the citric acid cycle, and oxidative phosphorylation.

Question 17

How is the rate of metabolic reactions affected by temperature?

Answer 17

Increase in temperature generally increases reaction rate, but if too high, can lead to denaturation of enzymes.

Question 18

How is the rate of metabolic reactions affected by pH?

Answer 18

Enzymes have optimal pH ranges. Deviation from this can decrease enzyme activity and thus reaction rate.

Question 19

What is leptin and its role in metabolism regulation?

Answer 19

Leptin is a hormone produced by fat cells. It signals the brain about energy stores, influencing food intake and energy expenditure.

Question 20

What is the role of the thyroid hormone in metabolism regulation?

Answer 20

Thyroid hormones increase the basal metabolic rate, affecting the metabolism of proteins, carbohydrates, and lipids.