Transport of Oxygen

Question 1

What does haem consist of?

Answer 1

4 pp chains- 2 a chains and 2 B chains

Question 2

What does each pp have?

Answer 2

Haem group (prosthetic group attached) which cont Fe3+

Question 3

What type of proteins are haem mol?

Answer 3

Conjugated proteins

Question 4

How is oxyhaemoglobin formed?

Answer 4

Each haem group can bind to an o2 mol-> oxyhaemoglobin

Question 5

What happens in high o2 levels and then in low o2 levels?

Answer 5

High: oxyhaem forms
Low: Oxyhaem dissociates

Question 6

In mammals where does oxyhaem form and dissoc. Why?

Answer 6

Oxyh forms in lungs where o2 levels are high due to rapid g.e in lungs and dissoc takes place in tissues where O2 levels decreased due to resp

Question 7

How does a conformation change occur? What does this lead to?

Answer 7

When one o2 mol is taken up by a haem, there is a conformational change (distortion) in haem mol which leads to faster uptake of 3 remaining O2 mol (coop loading)

Question 8

What happens when one o2 mol binds?

Answer 8

Shape is distorted and this facilitates binding of 2nd O2 mol
Further str alt with 2 and 3 but each one facilitates much faster uptake of O2 than preceding one

Question 9

Descr blood sat at 100%

Answer 9

Every mol of haem in blood carries 4 O2 mol

Question 10

What is partial pressure?

Answer 10

O2 conc in env

Question 11

What is the loading tension?

Answer 11

Partial pressure at which haem is 95 % sat w O2

Question 12

What is the unloading tension?

Answer 12

Partial pressure at which haem is 50% sat w O2