Haemaglobin

Question 1

Loading

Answer 1

When oxygen is taken up by haemoglobin

Question 2

Unloading

Answer 2

When oxygen is released by haemoglobin

Question 3

Describe the structure of haemoglobin

Answer 3

Protein with a quaternary structure
4 subunits each with haem group

Question 4

How many oxygens can combine with one haem group

Answer 4

1

Question 5

Affinity

Answer 5

Chemical attraction

Question 6

Haemoglobin + oxygen =

Answer 6

Oxyhaemoglobin

Question 7

What calculation is used to find the % saturation of haemoglobin with oxygen

Answer 7

Oxygenated haemoglobin divided by maximum saturation

Question 8

Describe how haemoglobin normally loads oxygen in the lungs and unloaded it at tissue cells

Answer 8

1.Oxygen and haemoglobin combine creating oxyhaemoglobin
2. One haemoglobin can transport 4 oxygen molecules
3. High partial pressure of oxygen in lungs
4. Haemoglobin is 100% saturated
5. Unloads at low oxygen tension in tissue
6. Carbon dioxide increases oxygen disassociation

Question 9

Explain how oxygen in a red blood cells is made available for respiration in active tissue

Answer 9

1. CO2 increased respiration
2. Causes oxygen to disassociate from haemoglobin
3. Low partial pressure in tissue
4. Oxygen diffuses from red blood cells to tissue

Question 10

The oxygen disassociation curve is the foetus is to the left of the mother. Explain the advantage of this for the foetus

Answer 10

1. High affinity so loads more oxygen
2. At low and high partial pressures
3. Oxygen moves from mother to foetus

Question 11

Explain how oxygen is loaded transported and unloaded in the blood

Answer 11

1. Haemoglobin has high affinity for oxygen in red blood cells
2. Loading of oxygen in the lungs at high partial pressure
3. Unloaded at respiring cells at low partial pressure
4. Unloading linked to higher carbon dioxide concentration

Question 12

Binding of one molecule of oxygen to haemoglobin makes it easier for second oxygen molecule to bind

Answer 12

1. Binding of first oxygen changes quaternary structure of haemoglobin
2. Uncovers another binding site

Question 13

Describe and explain the effect of increasing carbon dioxide concentration on the dissociation of oxyhaemoglobin

Answer 13

1. Decrease haemoglobin affinity for oxygen
2. By decreasing blood PH

Question 14

Heat from respiration helps mammals to main constant body temp

Explain the relationship between the surface area to volume ratio of mammals and the oxygen dissociation curves of their haemoglobin

Answer 14

1. Smaller mammals has greater SA to Vol ratio
2. More heat lost
3. Greater respiration rate
4. Oxygen required for aerobic respiration
5. Haemoglobin releases more oxygen

Question 15

Explain the shape of the oxygen distribution curve

Answer 15

1. S shaped
2. Sigmodal curve

Question 16

Describe the effect of carbon dioxide on HB and relate to the Bohr shift

Answer 16

1. High carbon dioxide means decrease saturation of haemoglobin
2. Decrease its affinity for oxygen so more unloading
3. ODC shift to the right ( Bohr shift )