Chapter 1 - Structure & Function Of Proteins - Class 1 - Sept 06, 2024

Question 1

The main molecule in biochemistry

Answer 1

Enzyme

Question 2

Four levels of proteins

Answer 2

1. Primary
2. Secondary
3. Tertiary
4. Quaternary

Question 3

6 main functions of proteins

Answer 3

1. Mechanical function
2. Enzyme: biocatalyst
3. Oxygen carriage: hemoglobin (quaternary structure)
4. Regulatory signals: insulin (ligand)
5. 6.

Question 4

Simple proteins are composed only of

Answer 4

Amino acids

Question 5

Proteins composed of additional elements such as heme and not only amino acids are

Answer 5

Conjugated proteins

Question 6

Proteins are major nitrogen-containing compounds composed of 5 major elements

Answer 6

1. Carbon
2. Oxygen
3. Nitrogen
4. Hydrogen
5. Sulphur

Question 7

Amino acids used to construct proteins must be:

Answer 7

1. L-configuration
2. Alpha carbon
3. Optically active

Question 8

All amino acids are optically active or chiral except

Answer 8

Glycine

Question 9

Classification of amino acids based on the R group

Answer 9

1. Neutral non polar (aliphatic or aromatic R groups)
2. Neutral polar (uncharged)
3. Acidic
4. Basic

Question 10

Only imino acid

Answer 10

Proline, Pro, P

Question 11

Two important aromatic, neutral non-polar amino acid

Answer 11

1. Phenylalanine, Phe, F
2. Tryptophan, Trp, W

Question 12

Neutral polar amino acid that can form disulfide bonds

Answer 12

Cysteine, Cys, C

bond creates cystine
SH—SH becomes S—S

Question 13

3 Neutral polar amino acids whose side chains form hydrogen bonding

Answer 13

1. Serine, Ser, S
2. Threonine, Thr, T
3. Tyrosine, Tyr, Y

Question 14

All amino acids are ampholytes in solution and the ionization state varies with

Answer 14

pH

Question 15

Ultraviolet Absorption of 280nm occurs in proteins with these 3 amino acids

Answer 15

1. Tryptophan (Trp)
2. Tyrosine (Tyr)
3. Phenylalanine (Phe)

Question 16

There are usually 4 different non-covalent interactions in the protein structure

Answer 16

1. Charge-charge interactions
2. Hydrogen bond
3. Van der waals
   4.