Select all of the TRUE statements about the 20 common amino acids coded into pro

Question

Select all of the TRUE statements about the 20 common amino acids coded into proteins. Select all that apply. Each amino acid has a specific side chain attached to the alpha carbon The amino group is attached to the alpha carbon. The carboxylic acid group is attached to the alpha carbon. The naturally occurring amino acids are D-amino acids. OAll free amino acids are soluble in water except those with a hydrophobic side chain Amino acids contain no charged groups at pH 7 The side chain of glutamine contains an amine group.

Explanation / Answer

True - Each amino acid has a specific side chain attached to alpha carbon.

True - The amino group is attached to the alpha carbon

True - The carboxylic acid group is attached to the alpha carbon.

False - Naturally occurring amino acids are D-amino acids. (Glycine is exception. Glycine can exist in either of two enantiomers, called L or D amino acids.

True - All free amino acids are soluble in water except those with a hydrophobic side chain.

False - Amino acids contain no charged groups at pH 7.
[Among the 20 common amino acids, five have a side chain which can be charged. At pH=7, two are negative charged: aspartic acid (Asp, D) and glutamic acid (Glu, E) (acidic side chains), and three are positive charged: lysine (Lys, K), arginine (Arg, R) and histidine (His, H) (basic side chains).]

False - The side chain of glutamine contains an amine group.
(side chain contains an amide group not amine group.)

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.