2.3.6 - Globular Proteins: Structure & Function

Question 1

Describe The Structure Of Globular Proteins

Answer 1

Compact, round proteins made up of multiple polypeptide chains.

Question 2

Why Are Globular Proteins Round When Folding Into Their Tertiary Structure?
(2 Points)

Answer 2

~ Their non-polar hydrophobic R groups are facing towards the centre of the protein.

~ Their polar hydrophilic R groups face towards the outside of the protein.

Question 3

Describe The Function Of Globular Proteins
(2 Points)

Answer 3

~ Orientation of the R groups makes them soluble in water, as the water molecules can surround the hydrophilic R groups.

~ Due to their solubility in water they can be easily transported around organisms and be involved in metabolic reactions.

Question 4

What Is An Example Of A Globular Protein?

Answer 4

Haemoglobin.

Question 5

Describe The Structure Of Haemoglobin
(5 Points)

Answer 5

~ Has a quaternary structure, made of 4 polypeptide chains, 2 alpha and 2 beta globin subunits.

~ Each globin subunit has a haem group.

~ Globin subunits are held together by disulphide bonds.

~ Hydrophobic R groups face inwards, maintains spherical shape.

~ Hydrophilic R groups face outwards, making haemoglobin soluble.

Question 6

Describe The Function Of Haemoglobin

Answer 6

Each haemoglobin molecule carries 4 oxygen molecules (8 oxygen atoms).