Section 3 pqs

Question 1

Describe +explain how the structure of the human heart is adapted to it’s function in maintaining an efficient blood supply to the body [6]

Answer 1

.4 chambers-ensures separation of oxygenated and deoxygenated blood
.left ventricle has a thicker wall-generate higher pressure to pump blood
.right ventricle has thinner wall-low pressure short distance to ventricles
.ATRIOVENTRICULAR valves (tricuspid and bicuspid)- prevents backflow of blood
.Semilunar valves-prevent backflow of blood into ventricles
.septum separates left+ right ventricles-maintaining different pressures+ preventing mixing of blood

Question 2

Explain how water from tissue fluid is returned to the circulatory system

Answer 2

.(plasma) proteins remain
.crates water potential gradient
.water moves (to blood) by osmosis
.returns (to blood) by lymphatic system

Question 3

Why does the hydrostatic pressure falls from the arteriole end of the capillary to the venule end of the capillary

Answer 3

Loss of water

Question 4

High blood pressure leads to an accumulation of tissue fluid. Explain how

Answer 4

High blood pressure=high hydrostatic pressure
increase outward pressure from (arterial) end of capillary
. so more tissue fluid formed/less tissue fluid reabsorbed

Question 5

Why is the water potential of the blood plasma more negative at the venule and of the capillary than the arteriole end of the capillary

Answer 5

.water has left capillary
.proteins (in blood) too large to leave capillary
.increasing conc of blood proteins