PATHOLOGY

Detailed explanation-1: -The capillaries, where the gaseous exchange occurs, merge into venules and these converge to form larger and larger veins until the blood reaches either the superior vena cava or inferior vena cava, which drain into the right atrium.

Detailed explanation-2: -Venules which are small vessels that collect blood from the tissues, converge to form veins.

Detailed explanation-3: -The arteries diverge into narrow arterioles, and then further diverge into capillaries. The blood in the capillaries is collected into venules. The venules converge into veins that carry the blood to the heart.