Which Statement Concerning the Twenty Different α-Amino Acids Widely Found

question 22

Multiple Choice

Which statement concerning the twenty different α-amino acids widely found in nature is true?

• A) Each α-amino acid has a different number of carbon atoms.
• B) Each α-amino acid has one amino (−NH₂)group.
• C) Each α-amino acid has one carboxylic acid (−COOH)group.
• D) These α-amino acids differ in the R groups attached to the α-carbon.
• E) None of these α-amino acids are aromatic compounds.

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Definitions:

Erythrocytes

Red blood cells, which are responsible for carrying oxygen from the lungs to the body's tissues and returning carbon dioxide from the tissues back to the lungs.

Hct

Hematocrit; a measure of the proportion of blood volume that is occupied by red blood cells, typically expressed as a percentage.

HCT

Hematocrit, a measure of the proportion of blood volume that is occupied by red blood cells.

Thymus

A lymphoid organ situated in the neck of vertebrates that produces T-cells for the immune system, especially important during early life.