3.3 Transport of Gases

Question 1

what percentage of blood is plasma

Answer 1

55%

Question 2

what percentage of blood is red blood cells

Answer 2

45%

Question 3

what percentage of blood is white blood cells and platelets

Answer 3

less than 1%

Question 4

another name for red blood cells

Answer 4

erythrocytes

Question 5

another name for white blood cells

Answer 5

leucocytes

Question 6

another name for platelets

Answer 6

thrombocytes

Question 7

what percentage of plasma is water

Answer 7

90%

Question 8

what is plasmas function

Answer 8

contains digested food products and distributes hear around the body

Question 9

3 adaptations of red blood cells

Answer 9

1. biconcave shape- giving them a large surface area so more oxygen can diffuse across the membrane
2. no nucleus- more room for haemoglobin so more oxygen can be transported
3. flexible- they can fit through very narrow lumen of the capillaries

Question 10

what are the two types of white blood cells

Answer 10

granulocytes

agranulocytes

Question 11

granulocytes

Answer 11

have granular cytoplasm and lobed nuclei, function is to engulf pathogens by phagocytosis

Question 12

agranulocytes

Answer 12

have a clear cytoplasm and spherical nucleus, produce antibodies and antitoxins

Question 13

platelets function

Answer 13

involved in blood clotting

Question 14

how many polypeptide chains does haemoglobin have

Answer 14

4

Question 15

what is the reversible reaction between haemoglobin and oxygen

Answer 15

Hb + 4O2 ——> Hb4O2

Question 16

affinity

Answer 16

one molecule having a chemical attraction for another

Question 17

saturation

Answer 17

percentage of oxygen associated compared with the maximum possible

Question 18

association

Answer 18

uptake of oxygen by haemoglobin to form oxyhemoglobin at the lungs

Question 19

dissociation

Answer 19

release of oxygen at the respiring tissues to form haemoglobin

Question 20

cooperative binding

Answer 20

describes the ease with which a haemoglobin molecule binds to a second and then a third oxygen molecule, compared with the first and fourth

Question 21

what is the shape of the oxygen dissociation curve

Answer 21

sigmoid

Question 22

foetal haemoglobin dissociation curve

Answer 22

shifted to left, has a nigher affinity for oxygen and therefore can load oxygen from the mothers blood at all partial pressures of oxygen

Question 23

llama and lugworm dissociation curve

Answer 23

shifted to left, llamas live at high altitude with low atmospheric pressure and lugworms in seawater where there is low oxygen saturation. The haemoglobin has a higher affinity for oxygen and so more readily takes it up at the lungs

Question 24

myoglobin

Answer 24

tertiary structured protein that is more stable than haemoglobin and acts as an oxygen store in muscle cells

Question 25

myoglobin dissociation curve

Answer 25

very far to the left, at every partial pressure of oxygen myoglobin has a higher percentage oxygen saturation than haemoglobin.
If oxygen partial pressure becomes very low, oxymyoghobin unloads its oxygen

Question 26

the Bohr effect dissociation curve

Answer 26

curve is shifted to the right, when partial pressure of co2 is high (due to production in respiring tissues) the conditions become more acidic. This causes haemoglobin to change shape slightly and so haemoglobin now has a lower affinity for oxygen, unloading oxygen to respiring tissues more readily.

Question 27

tissue fluid

Answer 27

fluid in tissues which is plasma

Question 28

lymph

Answer 28

fluid from tissues which does not drain back into the capillaries of the circulatory system