Circulatory systems: Practice Questions

What is the primary function of the circulatory system?

In the mammalian heart, the thickness of the muscular walls varies significantly between chambers. Which statement correctly explains the relative thickness of the muscle walls of the heart?

Which statement correctly compares the blood pressure in the two circuits of a mammalian double circulatory system?

In a double circulatory system, there are two distinct circuits. One circuit passes to the lungs; which structure does the other circuit primarily supply?

A diagram shows the following blood flow pathway in an organism:
Heart \(\rightarrow\) Lungs \(\rightarrow\) Heart \(\rightarrow\) Body \(\rightarrow\) Heart.
Which type of system does this diagram represent?

What is the crucial role of valves in the circulatory system?

Explain the key advantage of a double circulatory system, as found in mammals, over a single circulatory system.

Describe the specific role of platelets in the process of blood clotting and explain why the conversion of soluble fibrinogen to insoluble fibrin is essential for this process.

The circulatory system is responsible for the transport of materials around the body.
(a) Name the organ that provides the pressure to move blood through the vessels.
(b) Mammals have a double circulation. Identify the organ where the blood picks up oxygen.
(c) Fish have a single circulation. State the name of the organs where blood becomes oxygenated in a fish.
(d) State whether the blood entering the heart of a fish is oxygenated or deoxygenated.

(a) Explain why the muscular wall of the left ventricle in the mammalian heart is significantly thicker than the muscular wall of the right ventricle.
(b) Describe the importance of the septum in separating different types of blood.
(c) State the name of the blood vessels that supply the heart muscle itself with oxygen and nutrients.
(d) Identify two ways the activity of the heart can be monitored by a doctor.