Amino Acid Chem Revision

Question 1

aliphatic vs aromatic vs heterocyclic

Answer 1

aliphatic - no ring
aromatic- benzene ring
hetero- other type of ring

Question 2

branches chain amino acids

Answer 2

valine, leucine, isoleucine

Question 3

hydroxy (OH) amino acids

Answer 3

serine, homoserine, threonine

Question 4

Sulfur containing amino acids

Answer 4

cysteine, homocysteine, cystine, methionine

Question 5

COOH (acidic) amino acids

Answer 5

aspartic acid, glutamic acid

Question 6

amide form of acidic amino acid

Answer 6

asparagine, glutamine (not acidic)

Question 7

basic amino acids

Answer 7

lysine, hydroxy lysine, arginine, histidine

Question 8

histidine is

Answer 8

not aliphatic, heterocyclic but basic

Question 9

aromatic amino acids

Answer 9

phenyl alanine, tyrosine, tryptophan

Question 10

heterocyclic amino acids

Answer 10

histidine, tryptophan

Question 11

imino acids

Answer 11

proline, hydroxyproline

Question 12

21st amino acid

Answer 12

selenocysteine

Question 13

non polar amino acid

Answer 13

glycine, alanine, valine, isoleucine, leucine

Question 14

semi charged (uncharged) amino acid

Answer 14

contain OH, SH, and amide group

Question 15

charged Amino acid

Answer 15

basic and acidic

Question 16

primary structure
secondary structure
tertiary structure
quaternary structure are maintained by:

Answer 16

primary: peptide
secondary: hydrogen
tertiary: hydrophobic internation, ionic/electrostatic interactions, hydrogen bond, van der Waals forces, disulfide bond

Question 17

shape of 
primary structure
secondary structure 
tertiary structure
quaternary

Answer 17

1. random coil
2. folding into a helix and b pleated sheets
3. globular protein
4. 1+ polypeptide chain

Question 18

factors affecting helix formation

Answer 18

1. proline bc can’t form hydrogen bond
2. succesive bulky amino acids like tryptophan
3. successive basic or acidic amino acids bc repels

Question 19

a helix is

Answer 19

hydrophobic bc intrachain cellular hydrogen bonds

Question 20

chaperones def and examples

Answer 20

prevent misfiling of protein .

age lowers chaperones which can lead to alzhiemers and Parkinson’s

Question 21

changes due to denaturation

Answer 21

1. loss of secondary, tertiary and quaternary structure
2, low sollubility
3. high viscosity
4. high digestability
5. loss of biological activities
6. los of antigenic properties