Nutrition, Metabolism and Energy Balance

These flashcards cover key concepts from the lecture on nutrition, metabolism, and energy balance, focusing on protein metabolism, metabolic states, and hormonal regulation.

What needs to happen to proteins in the body due to their deterioration?

Proteins need to be continually broken down and replaced.

What happens to excess dietary amino acids?

They are oxidized for energy or converted to fat for storage.

What is deamination in amino acid degradation?

It is the process where the NH2 (amine group) is removed from the amino acid.

What are the three events of amino acid degradation?

Transamination, oxidative deamination, and keto acid modification.

What does the term transamination refer to?

It refers to the process by which an amine group is transferred from an amino acid to α-ketoglutaric acid.

What occurs during oxidative deamination?

The amine group of glutamic acid is removed as ammonia, regenerating α-ketoglutaric acid.

What are the major metabolites produced from keto acid modification?

Pyruvic acid, acetyl CoA, α-ketoglutaric acid, and oxaloacetic acid.

How is glucose synthesized from amino acids?

Through gluconeogenesis, where certain keto acids can be converted back to glucose.

What is the absorptive state in metabolism?

It is the state lasting for about 4 hours after eating, where anabolism exceeds catabolism.

What is the primary hormone controlling the absorptive state?

Insulin.

What is the goal of the postabsorptive state?

To maintain blood glucose by making glucose available and promoting fat use for energy.

What happens during the postabsorptive state to glucose levels?

Glycogenolysis in the liver and skeletal muscle increases, leading to a rise in blood glucose.

What does glucagon do in the postabsorptive state?

It stimulates glycogenolysis and gluconeogenesis in the liver.

What hormone is released in response to decreased blood glucose levels?

Glucagon.

What is the function of leptin in long-term regulation of food intake?

It indicates total energy stores in fat tissue and suppresses appetite.

How does the body regulate temperature during increased heat production?

Hypothalamus initiates heat-loss mechanisms such as sweating and dilation of blood vessels.

What is considered hyperthermia?

An elevated body temperature that can depress hypothalamus and lead to severe health issues.

What is the definition of basal metabolic rate (BMR)?

The energy needs of the body to perform essential activities, measured in a postabsorptive state.

What effect do omega-3 fatty acids have on cholesterol levels?

They lower cholesterol levels and help prevent clotting.