Protein function

Question 1

What type of oxygen dissociation curve does myoglobin show?

Answer 1

A hyperbolic curve

Question 2

When oxygen binds to haemoglobin, what happens to Fe?

Answer 2

It moves into the plane of the ring

Question 3

When oxygen is bound to haemoglobin, what state is it in?

Answer 3

The R state

Question 4

Oxygen binding promotes stabilisation of which state?

Answer 4

R state

Question 5

What is the ratio of BPG:Haemoglobin?

Answer 5

1:1

Question 6

What is BPG’s effect haemoglobin’s affinity for oxygen?

Answer 6

It decreases the affinity

Question 7

In Bohr shift, which way does the oxygen dissociation curve move and why is it advantageous?

Answer 7

It shifts to the right. It is advantageous as it allows for quicker release of O2 at tissues

Question 8

Foetal haemoglobin has a higher affinity for O2. True or false?

Answer 8

True

Question 9

Glycosylation of HbA forms……..

Answer 9

HbA1c

Question 10

Sickle cell anaemia is a ….. to …. in which chain?

Answer 10

It is a glutamate to valine in the B-globin chain

Question 11

What are thalassaemias?

Answer 11

Thalassaemias are a group of genetic disorders where there is an imbalance between the number of a- and b-globin chains

Question 12

Give the name of two allosteric effectors on haemoglobin

Answer 12

CO and BPG

Question 13

Give the example of an allosteric inhibitor of haemoglobin and explain its effect on the oxygen dissociation curve.

Answer 13

BPG is an example. It shifts the curve to the right and enhances the T state.

Question 14

What is a prosthetic group?

Answer 14

A non-amino acid group (either organic or inorganic) found in proteins