Haemoglobin

Question 1

how much oxygens can bind to haemoglobin

Answer 1

4

Question 2

what is meant by loading / association

Answer 2

when oxygen is taken up by haemoglobin

Question 3

what is meant by unloading / dissociation

Answer 3

when oxygen is released by haemoglobin

Question 4

what is meant by affinity

Answer 4

natural attraction

Question 5

what is meant by partial pressure

Answer 5

the amount of a particular gas in a mixture of gases

Question 6

1. is the partial pressure of oxygen in the lungs high or low
2. is the affinity high or low for oxygen in the lungs

Answer 6

1. high
2. high

Question 7

1. is the partial pressure of oxygen in the tissue high or low
2. is the affinity for oxygen in the tissues high or low

Answer 7

1. low
2. low

Question 8

what happens if the affinity for oxygen is low

Answer 8

dissociation

Question 9

where does oxygen load

Answer 9

at the lungs where there is alot of oxygen

Question 10

where does oxygen unload

Answer 10

at respiring tissues where there is a demand for it

Question 11

explain why there is a lower affinity for oxygen at respiring tissues

Answer 11

• at respiring tissues there is a higher concentration of carbon dioxide
• carbon dioxide dissolves in the blood, forming carbonic acid
• this lowers the pH of the blood, makng it more acidic
• this alters the shape of haemoglobin, lowering its affinity

Question 12

explain why the first oxygen to bind to haemoglobin is slow but it is faster for the rest of the oxygen

Answer 12

• the first oxygen molecule combines slowly
• the binding of the first molecule causes the tertiary structure of haemoglobin to change
• this exposes the rest of the oxygen binding sites, making it easier for the other oxygen mlecules to bind

Question 13

what is the Bohr effect

Answer 13

where the curve shifts to the right

Question 14

describe the advantage of the Bohr effect during intense exercise

Answer 14

• lower affinity for oxygen
• more unloading of oxygen
• more oxygen supplied to aerobically respiring tissues

Question 15

explain the type of haemoglobin an organism will have that lives in a low oxygen environment and the effect this has on the oxgen dissociation curve

Answer 15

• high affinity for oxygen
• oxygen dissociation curve will shift to the left

Question 16

• explain the type of haemoglobin an organism will have who has high activity levels
• what is the effect this has on the oxygen dissociation curve

Answer 16

• lower affinity for oxygen
• shifts to the right

Question 17

explain the affinity for oxygen when the oxygen dissociation curve is:

1. shifted to the left
2. shifted to the right

Answer 17

1. higher affinity
2. lower affinity