Biological Molecules - Proteins

Question 1

what are proteins

Answer 1

a diverse group of long chained complex polymer molecules made up of a long chain of amino acids

Question 2

name the 4 functions of protein

Answer 2

1. structure
2. catalytic
3. signalling
4. immunological

Question 3

how are proteins formed

Answer 3

condensation reactions

Question 4

what bonds are formed by condensation reactions between amino acids

Answer 4

peptide bonds

Question 5

what is the name for two amino acids bonded together

Answer 5

a dipeptide

Question 6

what is it called when more than 2 amino acids are bonded together

Answer 6

a polypeptide

Question 7

describe the primary structure of protein

Answer 7

simple long chains with no intermolecular bonds or interactions

Question 8

describe the secondary structure of protein (2 things)

Answer 8

1. hydrogen bonds causing protein to fold or coil
2. makes a alpha helix shape or a beta plated sheet shape due to hydrogen bonds between COOH group O and H in amino group

Question 9

describe the structure of tertiary protein

Answer 9

Amphipathic interactions, hydrogen bonds, ionic bonds and disulphide bonds keep molecule in place

Question 10

describe the structure of quatertery protein structure

Answer 10

1. Amphipathic interactions, hydrogen bonds, ionic bonds and disulphide bonds keep molecule in place
2. two separate polypeptide chains become interlinked

Question 11

name three factors that can cause protein to denature

Answer 11

1. change in temperature
2. change in pH
3. change in salt concentration

Question 12

what are globular proteins

Answer 12

globular proteins are folded into spherical shape with hydrophilic outside and hydrophobic inside. when denatured they become inactive and insoluble

Question 13

name 2 examples of globular proteins

Answer 13

1. enzymes

2. haemoglobin

Question 14

what are fibrous proteins

Answer 14

fibrous proteins are polypeptide chains that are cross liked for additional strength, insoluble and when denatured they loose their strength

Question 15

name 2 examples of fibrous proteins

Answer 15

1. keratin

2. collagen