Amino acids (1.1)

Question 1

Proteinogenic amino acids

Answer 1

20 alpha-amino acids encoded by human genetic code

Question 2

Are amino acids optically active

Answer 2

Yes. Amino acids are optically active

Question 3

Is glycine optically active

Answer 3

Glycine is not optically active

Question 4

All chiral amino acids are L/D amino acids

Answer 4

L amino acids

Question 5

Draw a general structure of D-amino acid

Answer 5

.

Question 6

Two amino acids that contain sulfur

Answer 6

1. Methionine
2. Cysteine

Question 7

Nonpolar, non-aromatic side chains

Answer 7

Glycine, alanine, valine, leucine, isoleucine, methionine, proline (2,5)

Question 8

3 amino acids with 3 side chains

Answer 8

Tryptophan, phenylalanine, tyrosine

Question 9

Do amide nitrogen gain or lose protons in changes in pH?

Answer 9

No

Question 10

Amino acids with Polar side chains

Answer 10

Serine, Threonine, Asparagine, Glutamine, Cysteine

Question 11

Amino acids with negatively charged side chains

Answer 11

Aspartic acid (aspartate for anion), Glutamic acid (glutamate for anion)

Question 12

Most acids exist in cells as deprotonated/protonated forms

Answer 12

Deprotonated

Question 13

Amino acids with positively charged side chain

Answer 13

Arginine, Histidine, Lysine