Protein Metabolism Study

Question 1

What is the average protein content in a 70kg male?

Answer 1

10-12kg of protein

This represents 60-75% of protein within skeletal muscle.

Question 2

What role do proteins play in the body?

Answer 2

Unique roles within a cell

Examples include enzymes, structural components, transport, hormones, immunology, and regulatory functions.

Question 3

What are the building blocks of proteins?

Answer 3

Amino Acids

Amino acids are linked by peptide bonds.

Question 4

How many amino acids are there?

Answer 4

20 amino acids

9 are essential and 11 are non-essential.

Question 5

What are essential amino acids?

Answer 5

Amino acids that must be consumed

They include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Question 6

What are non-essential amino acids?

Answer 6

Amino acids that can be synthesized in the body

Examples include alanine, arginine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline, serine, and tyrosine.

Question 7

What is protein turnover?

Answer 7

A continual state of turnover of proteins

This involves synthesis of new proteins and degradation of old ones.

Question 8

What enzymes are involved in protein digestion?

Answer 8

Pepsin, Trypsin, Chymotrypsin, Carboxypeptidase, Elastase

Pepsin acts in the stomach; others act in the small intestine.

Question 9

What is the free amino acid pool composition?

Answer 9

Glutamate 60%, Glutamine 14%, Alanine 4%

This pool is crucial for amino acid metabolism.

Question 10

What is the primary energy source for the body?

Answer 10

Not considered primary energy source

Proteins are primarily used for energy during fasting or low energy intake.

Question 11

What is the role of the TCA Cycle in amino acid metabolism?

Answer 11

Involves deamination or transamination

Amino acids enter the TCA cycle for energy metabolism.

Question 12

What is deamination?

Answer 12

Removal of amino group as ammonia

Ammonia is converted to urea for excretion.

Question 13

What percentage of nitrogen is excreted in urea?

Answer 13

90% of nitrogen

Ammonia is converted to urea to mitigate toxicity.

Question 14

Fill in the blank: The amino acid pool in the body consists of _______ and _______.

Answer 14

free amino acids and protein reserves

This pool is essential for various metabolic processes.

Question 15

True or False: All proteins in the body are synthesized from essential amino acids only.

Answer 15

False

Non-essential amino acids can also be synthesized from other amino acids.