CO2 and O2

Question 1

How is oxygen tension reduced in the placenta

Answer 1

In placenta absorb 02 from fluid reducing oxygen tension
O2 diffuses from mother to blood
Reduces O2 tension further which makes maternal haemoglobin release more O2

Question 2

What happens to the haemoglobin after the first O2 has binded

Answer 2

It undergoes a conformational change

Question 3

How is Co2 transported

Answer 3

• plasma
• haemoglobin to carbaminohaemoglobin
• hydrogen carbonate ions

Question 4

Formation of hydrogen carbonate ions

Answer 4

1) combines with water to from weak carbon acid
2) reaction catalysed by carbonic anhydrase
3) Hydrogen carbonate ions and hydrogen dissociates
4) Hydrogen carbonate ions diffuse out of RBC to plasma
5) Chloride ions diffuse in to maintain pH - the chloride shift
6) to prevent H+ building up and causing RBC to become acidic taken out of solution and associates with haemoglobin to form haemoglobinic acid

Question 5

Bohr effect

Answer 5

H+ ions acidic changing pH of cytoplasm
disrupts tertiary structure and reduces affinity for O2
more O2 released