Haemoglobin And Gas Transport

Question 1

What doe haemoglobin increase the oxygen carrying capacity to?

Answer 1

200ml

Question 2

Why do gases not travel in the gaseous phase in plasma?

Answer 2

It would result in bubbles = air embolism

Question 3

What percentage of arterial 02 is extracted by tissues at rest?

Answer 3

25%

Question 4

What percentage of oxygen in arterial blood is bound to Hb?

Answer 4

98%

Question 5

How many molecules of oxygen bind to have ogle in and therefore what volume of oxygen is bound to each gram of Hb?

Answer 5

4 molecules per 1 Hb molecule

1.34ml 02 per gram of Hb

Question 6

What is the main Hb in RBC?

Answer 6

HbA2

Question 7

The degree to which Hb is saturated with oxygen is determined by?

Answer 7

Partial pressure of oxygen

Question 8

Hb saturation is complete when in contact with alveoli for how long?

Answer 8

0.25s

Total contact time 0.75s

Question 9

The resting cell has a partial pressure of 40mmHg, what is the percentage of 02 bound to Hb?

Answer 9

75%

Question 10

What is anaemia?

Answer 10

Anaemia is defined as any condition where the oxygen carrying capacity of the blood is compromised

Question 11

What are causes of deficiency’s in oxygen carrying capacity in anaemia?

Answer 11

Haemorrhage
Iron deficiency
Vitamin B12 deficiency

Question 12

In anaemia is the partial pressure of oxygen low or is the total blood oxygen low?

Answer 12

The Pa02 is normal despite there being a low total blood 02 content.
Note: it is not possible to have a low Pa02 but normal blood 02

Question 13

Is it possible for RBC to be fully saturated with 02 in anaemia?

Answer 13

Yes because Pa02 is normal
Only exception is in iron deficiency where the number of 02 binding sites on Hb will be reduced, but those present will still be saturated.

Question 14

What factors cause a decrease in haemoglobin saturation?

Answer 14

Decrease in PH
Increase in PC02
Increase in temp
Increase in DPG

Question 15

What factors cause an increase in haemoglobin saturation %?

Answer 15

Increase in PH
Decrease in temp
Decrease in PC02
Decrease in DPG

Question 16

What are the symptoms of CO poisoning?

Answer 16

Hypoxia 
Anaemia
Nausea
Headaches
Cherry red skin
Mucous membranes
Respiratory rate unaffected due to normal arterial PC02

Question 17

A PC0 of only ….. causes progressive carboxyhaemoglobin formation?

Answer 17

0.4mmHg

Question 18

By how many times greater is the affinity of Hb to C0 compared to 02?

Answer 18

250 times greater

Question 19

What are the 5 main types of hypoxia?

Answer 19

Hypoaemia hypoxia
Anaemia hypoxia
Stagnant hypoxia
Histotoxic hypoxia
Metabolic hypoxia

Question 20

Does hyperventilation bring about respiratory acidosis or alkalosis?

Answer 20

Blowing off more C02 will result in a decrease of H+ bringing about respiratory alkalosis

Question 21

Will hypoventillation bring about respiratory acidosis or alkalosis?

Answer 21

Acidosis because hypoventillation causes C02 retention which leads to increased H+

Question 22

Carbon dioxide travels in venous blood mostly in which form?

Answer 22

As carbonic acid within red blood cells

Question 23

What does the term chloride shift refer to?

Answer 23

The exchange of chloride ions for bicarbonate ions across the red blood cell membrane
(In the C02 process)

Question 24

What is the main determinant of haemoglobin oxygen saturation?

Answer 24

Plasma p02

Question 25

Levels of what haemoglobin molecule can indicate blood glucose levels over a long period of time?

Answer 25

HbA1a-c

Question 26

During a period of intense excessive, what happens to the affinity of haemoglobin for oxygen at skeletal muscle?

Answer 26

During intense exercise, the C02 would increase as the oxygen demands increase, and therefore would cause the affinity to decrease

Question 27

In a patient with haemorrhaging anaemia they have a low blood oxygen content.
Would you expect the plasma P02 to be increase/decreased or normal?

Answer 27

P02 would be normal because there is no problems with the lungs so diffusion is unimpaired.