The Anatomy and Physiology of Animals/Heart Worksheet/Worksheet Answers

1. The diagram below shows an external view of the mammalian heart.



2. The diagram below shows a section through the heart seen from the same direction as the external view in question 1.



3. Choose words from the list to complete the sentences below.


 * a) The top two chambers of the heart are called atria.
 * b) These structures stop blood flowing backwards into the atria. Atrioventricular valves
 * b) This side of the heart receives oxygenated blood. Left hand side
 * c) This is the largest artery in the body. Aorta
 * d These are blood vessels that carry blood towards the heart. Veins
 * e) This structure sets the speed of the heat beats. Pacemaker
 * g) This blood vessel supplies the heart muscle with oxygenated blood. Coronary artery

4. Fill in the name of the blood vessel in the table below. 5. What is the odd one out?
 * a) Right atrium, right ventricle, pulmonary artery, caudal vena cava, aorta.


 * The aorta is the only structure in the list that carries oxygenated blood.
 * b) Left atrium, left ventricle, right ventricle, pulmonary veins, aorta, coronary artery.


 * The right ventricle is the only structure in the list that carries deoxygenated blood.

6. Arrange these events of one complete heart beat cycle in the correct order starting with F.
 * F. Deoxygenated blood flows from the caudal and cranial vena cavae into the right atrium.
 * H. The right atrium contracts
 * B. The blood flows through the right atrio-ventricular valve into the right ventricle.
 * I. The right ventricle contracts and blood flows along the pulmonary artery to the lungs
 * G. The deoxygenated blood picks up oxygen
 * C. Oxygenated blood flows along the pulmonary veins into the left atrium
 * E. The left atrium contracts
 * D. The blood passes through the left atrio-ventricular valve into the left ventricle
 * A. The left ventricle contracts and blood flows along the aorta to the body

7. The first hearts sound is produced by:


 * b) The atrio-ventricular valves closing

8 The second heart sound is caused by:
 * a) The semilunar valves closing