Carbon Dioxide In The Blood

Question 1

What are the content of CO2 in aterial blood?

Answer 1

21 mmol.l

Question 2

What is the total content of O2 in aterial blood?

Answer 2

8.9 mmol.l

Question 3

What happens to carbon dioxide in plasma?

Answer 3

Dissolved CO2 reacts with water to form carbonic acid, which quickly dissoicates to hydorgen ions and carbonate ions,

Question 4

How do you determine thepH of the plasma?

Answer 4

Depends how much CO2 reacts to form and fhe concentration of hydorgen carbonate

Question 5

What happens to plasma pH is the pCO2 rises?

Answer 5

The plasma pH will fall

Question 6

What happens to the plasma pH is the PCO2 falls?

Answer 6

The plasma pH will rise

Question 7

What is the plasma concentration of HCO3-?

Answer 7

25 mmol (mostly associated with Na+ not H+’

Question 8

What is the enzyme is red blood cells use to drive the production of hydrogen carbonate?

Answer 8

Carbonic anhydrase

Question 9

What happens to the hydrogen carbonate produced?

Answer 9

H+ binds to the negatively cahrdged hydrogen carbonate and allows the reaction to proceed in the forward direction

Question 10

What is the role of the kdiney in controlling HCO3- ?

Answer 10

It controls it by varying the excretion

Question 11

What are the properties of haemoglobin are important for the buffering of CO2?

Answer 11

Buffering of H+ by hb depends on the level of oxygenation, if Hb is in the r state with more oxygen bound then less H+ ions bind, as at the lungs, but if there is less oxygen bound and the hameoglobin is in the t state more oxygen is bound, and is Hb bings more in cells than more HcO3- can be lroducedd

Question 12

What happens ip venous blood with regards to CO2?

Answer 12

Hb has lost O2 and therefore binds more H+, allowing more HCO3- to form which is exported to the plasma, and this can cope with the extra dissolution of CO2

Question 13

What happens when venous blood goes to the lungs?

Answer 13

Hb picks up the O2 and goes into the R state, and this causes Hb to give up the extra H+ it took on at the tissues, and the H+ reacts with HCO3- to for, CO2 which is breathed out

Question 14

How do carboamino compunds form?

Answer 14

CP2 can bind directly to rpteins and the amine groups on the globin of ahv, and this binding of molecular CO2 contributes to Co2 transport and not the acid base balance

Question 15

What are the different ways that CO2 is transported and the different compounds that are transported this wat?

Answer 15

60% travels as hydrogne carbonate, 30% travel as carboamino compounds and 10% travels as dissolved CO2