transport systems

Question 1

double circulatory system

Answer 1

blood passes through heart twice on one complete circuit of body

Question 2

closed circulatory system

Answer 2

circulatory system made up of vessels containing blood

Question 3

artery layers

Answer 3

inner endothelium
middle layer made of elastic and collagen fibres
outer layer made of collagen and elastic fibres

Question 4

endothelium adaptations

Answer 4

smooth, single layer of squamous epithelial cells

Question 5

muscles in artery

Answer 5

for constriction and dilation
allow wall to stretch as pulses of blood surge through at high pressure

Question 6

plasma

Answer 6

flows through capillaries and some plasma leaks out through gaps in endothelium flowing into spaces between cells of tissue

Question 7

tissue fluid

Answer 7

less proteins than plasma fluid as they are too large to pass through capillary endothelium. wbc can fit roc too large

Question 8

bohr shift

Answer 8

decrease in affinity of haemoglobin for oxygen that occurs when co2 is present

Question 9

cardiac cycle steps

Answer 9

atrial systole
ventricular systole
ventricular diastole

Question 10

atrial systole

Answer 10

atria contract
blood flows from atria into ventricles
back flow stopped by closure of valves in veins

Question 11

ventricular systole

Answer 11

ventricles contract
atrioventricular valves pushes shut by pressurised blood in ventricles
semilunar valves in aorta and palomanry artery pushed open
blood flows from ventricles to arteries

Question 12

co2 conc dissociation curve

Answer 12

more co2 shift to the right

Question 13

co2 journey

Answer 13

produced by respiring cells
it diffuses from the cells into the blood plasma and then diffuses into rbc
carbonic anhydrase catalyses reaction with co2 and water to make carbonic acid H2co3
carbonic acid dissociates into h+ions and HCO3-
haemoglobin combines with hydrogen ions making haemoglobin acid HHb and oxygen is released

Question 14

chloride shift

Answer 14

chloride ions move into rbc from blood plasma down electrochemical gradient to balance the movement of hydrogencarbonate ions into the plasma from the red blood cells

Question 15

fetal haemoglobin

Answer 15

needs to be better at absorbing oxygen as by the time oxygen reaches placenta oxygen saturation has decreased
higher affinity to survive at low partial pressure
shift to right