Amino acids and proteins

Question 1

Which amino acids carry a net negative charge at physiologic pH (~7)?

Answer 1

Acidic Amino acids

Question 2

At physiologic pH, basic functional groups will be

Answer 2

Protonated

Question 3

What happens when an amino acid is protonated?

Answer 3

It attains a positive charge

Question 4

A polypeptide with a net positive charge at physiologic pH most likely has a

Answer 4

Basic R group

Question 5

Change in pH are unlikely to

Answer 5

• Alter Amino Acid sequence

- Break peptide bonds

Question 6

What kind of structure does Proline have?

Answer 6

Cyclic

Question 7

Proline plays a central role in the

Answer 7

Formation of secondary structures

Question 8

Where is proline found in alpha helices?

Answer 8

In the beginning

Question 9

Where is proline found in beta sheets?

Answer 9

At the turns

Question 10

Aliphatic amino acids are

Answer 10

• Nonpolar

- Hydrophobic

Question 11

What are the Aliphatic AAs?

Answer 11

GAVIL

Question 12

The isoelectric point for a polypeptide is the

Answer 12

pH at which the molecule does not have a net charge

Question 13

Tertiary structure is primarily due to

Answer 13

R group interactions between the amino acids that make up the protein

Question 14

What are the R group interactions involved in tertiary structure?

Answer 14

• Hydrogen bonding
• Ionic bonding
• Dipole-dipole interactions
• London dispersion forces

Question 15

A peptide bond is formed between

Answer 15

• Carboxyl group of Amino Acid

- Amino Group