Integration of metabolism

Question 1

Absorptive state

Answer 1

Timing:
Occurs after a meal, typically within the first few hours of eating.

Nutrient Absorption:
Nutrient Availability: High levels of nutrients are available in the bloodstream, especially glucose, amino acids, and fatty acids.
Primary Source: Digested nutrients from the recent meal.
Insulin Release:

Insulin:
Insulin is released by the pancreas in response to elevated blood glucose levels. Insulin promotes the storage of nutrients, facilitating their uptake by cells.

Liver Activity:
Glycogenesis:
The liver converts excess glucose into glycogen for storage.
Lipogenesis: Excess nutrients are converted into triglycerides (fat) for storage.

**Cellular Uptake: **
Cells take up nutrients for energy production and storage.

Question 2

Post-Absorptive State:

Answer 2

Timing:
Occurs between meals, typically several hours after eating.

Nutrient Absorption:
Nutrient Availability:
Blood glucose levels decrease as nutrients from the previous meal are used for energy.
Primary Source: Stored nutrients, such as glycogen and triglycerides.

Insulin Release:
Insulin: Insulin levels decrease as blood glucose levels decrease. Glucagon is released to promote the breakdown of glycogen into glucose.

Liver Activity:
Glycogenolysis: The liver breaks down glycogen into glucose to maintain blood glucose levels.
Gluconeogenesis: The liver synthesizes glucose from non-carbohydrate sources, such as amino acids and glycerol.

Cellular Uptake:
Cells rely on stored nutrients for energy production during this fasting state.