Question

Which structures of the heart control the flow of the blood?
A) Arteries
B) Veins
C) Valves
D) Capillaries

Answer 1

Hint: It acts as an inlet and outlet of the blood and present on each end of the ventricles. They prevent the backflow of the blood and allow the blood to flow in one direction only.

Complete step-by-step answer:
A. The arteries are the blood vessels, which carry oxygenated blood from the heart to all body parts. These are muscular tubes and lined by smooth tissue. It has three layers that are intima, media and adventitia. The aorta is the largest artery, which connects to the left ventricle. The deoxygenated blood carried by the pulmonary arteries from the heart to the lungs.
B. The veins are the blood vessels which carry deoxygenated blood from tissue (body part) back to the heart. Except for the umbilical vein and pulmonary vein, they carry oxygen-rich blood to the heart. It also has three layers like arteries (intima, media and adventitia).
C. The heart is a four-chambered, two atria (upper chamber) and two ventricles (lower chamber). Before the blood leaves each chamber it passes through the valves. It prevents the backflow of the blood. These valves are actual muscular flaps and located on each end of the lower chamber that is (each ventricle). All valves have three flaps or cusps called tricuspid valves except the mitral valve, it is a bicuspid valve.
D. The capillaries are the tiny blood vessels. It connects the arteries to the veins. They help to deliver the oxygen and other nutrients to individual cells of the body. It also exchanges the wastes between the body and tissues.

Hence the correct answer is option B.

Note: The heart has the following valves:
Tricuspid valves – guard the opening between the right atrium and right ventricle
Pulmonary valve - guard the opening between the pulmonary artery and right ventricle
Mitral valve - guard the opening between the left ventricle and left atrium
Aortic valve - guard the opening between the aorta and left ventricle