Globular Proteins:

Question 1

What is the shape of globular proteins?

Answer 1

= spherical shape

Question 2

Why is globular protein soluable in water?

Answer 2

= hydrophilic amino acids on the surface
= can interact with water

Question 3

What is in the centre of these globular proteins?

Answer 3

= centre of the protein has hydrophobic amino acids
= away from water molecules

Question 4

What protein is haemoglobin?

Answer 4

= globular
= 4 polypeptide sub units
= 2 alpha sub unit
= 2 beta sub units

Question 5

In haemoglobin what does each sub-unit contain ?

Answer 5

= prosthetic group
= haem
= contains an Fe2+ ion
= where oxygen binds
= 1 haemoglobin molecule can bind 4 oxygen molecules

Question 6

What happens when oxygen attaches to haemoglobin?

Answer 6

= quaternary structure changes slightly
= easier for more oxygen to attach
=

Question 7

What is insulin?

Answer 7

= Hormone carried in the blood stream
= role in blood glucose regulation
= carry out function by binding to specific receptor cells

Question 8

What does insulin consist of?

Answer 8

= 2 polypeptide chains
= linked by disulfide bonds
=

Question 9

What are receptors?

Answer 9

= protein found on the cell membrane of target cells
= shape of insulin molecule fits perfectly into the receptor
= slight changes could prevent binding effectivley

Question 10

What is the key feature of enzyme proteins?

Answer 10

= only react with a specific substrate molecule
= due to structure of enzymes
= chain folds to form a groove on the surface (active site) that only fits with a specific substrate