Cardiovascular System- Transportation Of Oxygen

Question 1

Plasma

Answer 1

Fluid part of the blood that surrounds blood cells and transports them

Question 2

Haemoglobin

Answer 2

Haemoglobin an iron containing pingment found in red blood cells, which combines with oxygen to form oxyhaemoglobin

Question 3

Myoglobin

Answer 3

Aka ‘muscle haemoglobin’
It is an iron containing pingment in slow twitch fibres which has a higher affinity for oxygen than haemoglobin. It stores the oxygen in the muscle fibres which can be used quickly when exercise begins

Question 4

Mitochondria

Answer 4

Known as the ‘powerhouse’ of the cell as respiration and energy production occur there

Question 5

Bohr shift

Answer 5

When an increase in blood carbon dioxide and a decrease in pH (measure of acidity) results in a reduction of the affinity of haemoglobin for oxygen
-during exercise S-shaped curve shifts to the right because when muscles require more oxygen, the dissociation of oxygen from haemoglobin in the blood capillaries to the muscle tissue occurs more readily

Question 6

Bohr shift
The 3 factors responsible for this increase in the dissociation of oxygen from haemoglobin which results in more oxygen being available for use by the working muscles are:

Answer 6

Increase in blood pressure
-when blood and muscle temperature increases during exercise, oxygen will dissociate from haemoglobin more readily

Partial pressure of carbon dioxide increases
-as the level of blood carbon dioxide rises during exercise, oxygen will dissociate faster from the haemoglobin

pH
-more carbon dioxide will lower the pH in the blood. A drop in blood pH will cause oxygen to dissociate from haemoglobin more quickly

Question 7

Arterio-venous difference (A-VO2 diff)

Answer 7

The difference between the oxygen content of the arterial blood arriving at the muscles and the venous blood leaving the muscles

• during rest difference is low
• during exercise much more oxygen is needed from the blood for the muscles so the difference is high

This increase will effect gaseous exchange at the alveoli so more oxygen is taken in and more carbon dioxide is moved

Training also increases the A-VO2 diff as trained performers can extract a greater amount of oxygen from the blood

Question 8

Diffusion of oxygen at the alveoli is helped enormously by their structure
Structure acronym

Answer 8

B -big surface area
O- one cell thick
G- good blood supply

BOG