Gas Transport 1

Question 1

What is Henry’s law

Answer 1

The amount of a given gas dissolve in a given type and volume of liquid at a constant temp is
Proportional to a pp of the gas in equilibrium with the liquid

Question 2

What does Henry’s law mean in relation to a gas pp

Answer 2

Means if pp in gas phase increased conc of gas in liquid phase would increase proportionally

Question 3

The pp of a gas in sol is

Answer 3

It’s pp in gas mix with it is in equilibrium

Question 4

Under resting conditions dissolved oxygen is taken up in tissues by

Answer 4

Dos solved oxygen

15ml/min

Question 5

What at strenuous exercise oxygen taken up as

Answer 5

Dissolved

90ml/min

Question 6

What is the resting consumption of body cells for oxygen

Answer 6

250ml/min

Question 7

What happens to oxygen consumption with strenuous exercise

Answer 7

Increase 25 fold

Question 8

How is oxygen mostly transported in the blood

Answer 8

Bound to Hb

Question 9

What is normal Po2 arterial

Answer 9

13.3 kPa

Question 10

What is a normal Hb conc

Answer 10

15 grams/100ml

Question 11

What are the two present forms of oxygen in the blood

Answer 11

Bound to Hb

Physically dos solved

Question 12

What is the interaction between Hb nd oxygen

Answer 12

Reversible combination
Hb has 4 haem groups which each bunds an oxygen
Hb fully saturated when oxygen binds

Question 13

What is the primary factor which determine the percent saturation of Hb with oxygen

Answer 13

Po2

Question 14

What is the oxygen delivery index

Answer 14

DO2I = CaO2 x C

CaO2 - oxygen content arterial blood
CI - cardiac index

Question 15

Oxygen delivery to tissues is a function of

Answer 15

Oxygen content of arterial blood and the cardiac output

Question 16

How do u work out the oxygen content of arterial blood

Answer 16

CaO2 = 1.34 x Hb x SaO2

1.34 - one gram Hb can carry this much oxygen when fully saturated
SaO2 - percent Hb saturated with oxygen (determined by Po2)

Question 17

What can impair oxygen delivery to the tissue

Answer 17

RESP disease
Heart failure
Anaemia

Question 18

What does binding oxygen to Hb do

Answer 18

Increases the affinity of Hb for oxygen for

Cooperatively and sigmoid

Question 19

What is the significance of sigmoid

Answer 19

Flat upper portions meads there is a moderate fall in alv po2 and will not affect oxygen loading

Steep loser part - tissues get lot of oxygen for a small drop in capillary po2

Question 20

What is the Bohr effect

Answer 20

When the Hb and oxygen curve of spdissociatikn shift to the right
Increased release oxygen by conditions at the tissue

Question 21

What is foetal Hb

Answer 21

HbF differs as has 2 alpha and 2 gamma subunits

Interacts less with 2,3- biphosphoglcerate in RBC

HbF has a higher affinity for oxygen
So dissociation curve shift to left

Allow oxygen to move form mother to foetus even is po2 low

Question 22

Where is myoglobin present

Answer 22

Skeletal and cardiac muscle

Question 23

What does myoglobin have and do

Answer 23

Has one haem group per mol 
No coop binding with oxygen 
Dissociation curve hyperbolic 
Myoglobin releases oxygen at low po2 
Short time storage for oxygen for anaerobic conditions 
If in tissue indicate muscle damage