Lecture 5

Question 1

8 functions of proteins

Answer 1

1. Enzymatic
2. Defensive
3. Storage
4. Transport
5. Hormonal
6. Receptor
7. Contractile
8. Structural

Question 2

Monomers of proteins

Answer 2

Amino acids

Question 3

How many am ac are there

Answer 3

20 diff (differ in R groups)

Question 4

Cov bond between am ac is

Answer 4

Pep tide bond

Question 5

What rx is the formation of peptide bond

Answer 5

Condensation rx

Question 6

Prots also called

Answer 6

Polypeptides (many peptide bonds)

Question 7

Prot shape determines what

Answer 7

Function

Question 8

Two diff shapes of prots

Answer 8

Fibrous and globular

Question 9

Role of fibrous prots

Answer 9

Primarily structural

Question 10

Where are fibrous prots

Answer 10

Many in EM and in connective tissues for strength and joint mobility

Question 11

Fibrous prots structure

Answer 11

Long and narrow

Question 12

Ex of fibrous prots

Answer 12

Collagen, keratin, elastin, silk

Question 13

Globular prots structure

Answer 13

Typically round in shape

Question 14

Globular prots functions

Answer 14

Enzymes, cellular messengers, molecular transporters

Question 15

Globular prots are often soluble in

Answer 15

Aqueous enviros

Question 16

Ex of globular prots

Answer 16

Hemoglobin, antibodies, enzymes

Question 17

Slight change in prot structure can

Answer 17

Affect its function (ex sickle cell)

Question 18

What is sickle cell disease

Answer 18

Single am ac substitution that causes cell to be rigid/mis-shaped

Question 19

What does sickle cell disease do

Answer 19

Cells stuck together snd block flow of blood/O2 -> pain, infections, tissue damage,loss of eyesight, blood clots and strokes

Question 20

What is hemoglobin (Hb)

Answer 20

Globular prot in RBC that transports O2, composed of 4 prot chains bound to heme group

Question 21

Each heme group has at its center

Answer 21

An iron atom

Question 22

One Hb molecule has 4

Answer 22

Sites to bind O2

Question 23

What is denaturation of proteins

Answer 23

When they change shape/unfold

Question 24

What happens if prot denatured

Answer 24

Loss of function

Question 25

4 ways to denature proteins

Answer 25

1. Heat
2. Pressure
3. Alcohol
4. Acids/bases

Question 26

Enzymes could not fold properly if

Answer 26

Out of their pH range (ex enzyme pepsin pH 2)

Question 27

How does heat denature

Answer 27

Molecules vibrate so rapidly-> disrupts non covalent bonds
(Ex cooking food, sterilization in medical)

Question 28

How can fevers be fatal

Answer 28

Denature prots (heat) including enzymes -> damages cells, tissues, organs

Question 29

Which alcohol is better

Answer 29

70%

Question 30

Why 70% instead of 95% alcohol

Answer 30

Bc 70% penetrates bacteria cells whereas 95% coagulates on outside of cell without entering

Question 31

Densturations are not strong enough to break cov bonds between am ac so

Answer 31

Some prots can recover