Question

Match the following:
$\begin{array}{cc}\text{1. Thebesian valve}& \text{a. Left auriculoventricular foramen}\\ \text{2. Mitral valve}& \text{b. Coronary sinus}\\ \text{3. Eustachian valve}& \text{c. Right auriculoventricular foramen}\\ \text{4. Tricuspid valve}& \text{d. Inferior vena cava}\end{array}$

• A. I-b, II-a, III-d, IV-c
• B. I-d, II-c, III-b, IV-a
• C. I-d, II-a, III-b, IV-c
• D. I-b, II-c, III-d, IV-a

Answer 1

The correct option is A I-b, II-a, III-d, IV-c

Valves are the structures which prevent the backflow of blood in the circulatory system.
Thebesian valve is the one which is present at the opening of the coronary sinus into the right atrium.

Mitral valve or the bicuspid valve guards the left auriculoventricular (AV) foramen and prevents the backflow of oxygenated blood from the left ventricle to the left atrium.

The Eustachian valve guards the opening of inferior vena cava (IVC) to the right atrium. The IVC drains the deoxygenated blood from the lower body parts to the right atrium.

The tricuspid valve is present at right AV foramen and prevents the backflow of deoxygenated blood from the right ventricle to the right atrium.