exchange surfaces (p2)

Question 1

how many oxygen can haemoglobin bind to

Answer 1

4

Question 2

what happens when one oxygen molecule binds to haemoglobin

Answer 2

molecule changes shape

makes it easier for the next oxygen molecule to bind

(positive cooperativity)

Question 3

describe the bohr effect

Answer 3

p.pressure of CO2 rises

haemoglobin gives up oxygen more easily

Question 4

what is the difference between fetal haemoglobin and adult haemoglobin

Answer 4

fetal has a higher affinity for oxygen

so it removes oxygen from maternal blood as they move past each other

Question 5

what happens to CO2 in the red blood cell

Answer 5

converted into carbonic acid (H2CO3-) catalysed by carbonic anhydrase

carbonic acid dissociates to form hydrogen carbonate ions and protons

the h. carbonate ions move out the cell into the plasma

chloride ions move in maintaining the electrical balance of the cell (chloride shift)

Question 6

what does haemoglobin also act as in the red blood cells

Answer 6

acts as a buffer

prevent changes in the pH by accepting free protons to form haemoglobinic acid

Question 7

describe what happens in diastole

Answer 7

heart relaxes

atria and then ventricles fill with blood