performs the work of the heart 20 The A fibrous skeleton B p

performs the work of the heart. 20. The A, fibrous skeleton B. pericardial cavity C. endocardium D. myocardium E. epicardium 21. The tricuspid valve regulates the opening between A. the right atrium and the left atrium. B. the right atrium and right ventricle. C. the right atrium and the left ventricle. D. the left atrium and the left ventricle. E. the left ventricle and the right ventricle. 22. oxygen-poor blood passes through A. the right AV (tricuspid) valve and pulmonary valve. B. the right AV (tricuspid) valve only. C. the left AV (bicuspid) valve and aortic valve. D. the left AV (bicuspid) valve only. E. the pulmonary and aortic valves

Solution

Option D is correct. Myocardium has voluntary action for pumping of blood.

Option B is correct. The valve is in between the both.

Option D is correct. Impure blood moves trhough bicuspid valve and then aortic semilunar valve.

Option B is correct. The gravity affects here, when blood enter in the right atrium to right ventricle, it gets closed.

Option C is correct. It is aortic semilunar valve.

Option B is correct. These pulmonary arteries carry impure blood to lungs.

Option D is correct. These are pulmonary veins.

Option C is correct. It also called Chordae tendineae.

Option D is correct. Through right atrium, it moves from pulmonary trunk to ascending aorta.