The differing thickness of the chambers in the mammalian heart comes from the amount of cardiac muscle each one contains. The atria contain less cardiac muscle than the ventricles, so their walls are thinner.
(a)[2]
Using their functions, explain why the atria have thinner walls than the ventricles.
(b)[1]
Name the wall that separates the right and left sides of the mammalian heart.
(c(i))[1]
State one clear difference between transpiration and translocation.
(c(ii))[1]
State one similarity between transpiration and translocation.
Worked solution & mark scheme
This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Atria pump blood over a short distance; ventricles pump blood over a long distance” …