Haemoglobin

Question 1

What is haemogloin

Answer 1

Water soluble globular protein

Question 2

What is the structure of haemoglobin

Answer 2

4 polypeptide chains, 2 beta and 2 alpha helices - so quaternary structure
4 associated haem groups as each oxygen binds to the haem ( fe2+ ) group
Each molecule can carry 4 o2 molecules

Question 3

What is affinity

Answer 3

How easily haemoglobin binds to oxygen

Question 4

What is loading/ association

Answer 4

Proscess of haemoglobin binding to oxygen

Question 5

What is unloading/ disassociation

Answer 5

When haemoglobin lets go/ unbinds to oxygen

Question 6

What is partial pressure

Answer 6

How much gas contributes to the pressure ie how concentrated a gas is

Question 7

What are the 3 factors that affect affinity

Answer 7

1: partial pressure of o2
2: oxygen saturation
3: partial pressure of carbon dioxide

Question 8

How does the partial pressure of o2 affect affinity

Answer 8

More oxygen equals higher affinity so more loading occurs

Question 9

How does oxygen saturation affect affinity

Answer 9

Low oxygen: low affinity, difficult to hold, more unloading
High oxygen: higher affinity, easier to load ,more loading

Question 10

How does partial pressure of co2 affect affinity

Answer 10

More co2 means lower affinity so more unloading

Question 11

What happens when you increase co2 in the blood
-ph
- respiring cells
- tertiary structure
- aerobic respiration
- delays

Answer 11

• increasing co2 in the blood will decrease the ph
• decrease in ph will affect the tertiary structure slightly
• lowering affinity so more o2 unloading or aerobic respiration therefore more energy from atp
• more o2 unloading delays anaerobic respiration so less lactic acid is produced and less cramps

Question 12

Describe and explain the advantage of the Bohr effect during intense exersise

Answer 12

• increased unloading of o2
• carbon dioxide reduces ph of blood so changed shape of hb
• more oxygen for aerobic respiration