The process of breaking down body protein into amino acids for energy is known as:

Correct Answer: D

Rationale: The correct answer is D: Catabolism. Catabolism involves the breakdown of body proteins into amino acids to be used as energy when there is an inadequate dietary intake. Choices A and B, deamination and transamination, involve the removal and transfer of amino groups, respectively, but not the breakdown of body proteins. Choice C, transcription, is a process in genetics where DNA is used to create mRNA, not related to breaking down body proteins.

Correct Answer: B

Rationale: The correct answer is B: Carbohydrates and fats. Carbohydrates are the body's primary and most efficient source of energy, providing fuel for daily activities. Fats are also a significant energy source, especially during times of prolonged or intense exercise. Proteins are primarily used for building and repairing tissues, not as a major energy source. Vitamins and minerals are essential for various bodily functions but do not serve as direct sources of energy.

Correct Answer: D

Rationale: The correct answer is the amino group. Amino acids consist of an amino group (NH2), a carboxyl group (COOH), a hydrogen atom, and a variable side chain attached to a central carbon atom. The amino group is essential for the formation of proteins. The carboxyl group is not the base component but another important functional group in amino acids. Carbon chain and radicals are not specific chemical structures that form the base component of an amino acid.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: The correct answer is D: 20. There are 20 different amino acids that combine to form proteins in the human body. Each amino acid has a unique side chain that determines its properties. Choices A, B, and C are incorrect as they do not represent the total number of different amino acids found in human proteins.