PATHOLOGY

Detailed explanation-1: -Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vessels.

Detailed explanation-2: -In blood vessels, most of the resistance is due to vessel diameter. As vessel diameter decreases, the resistance increases and blood flow decreases. Very little pressure remains by the time blood leaves the capillaries and enters the venules.

Detailed explanation-3: -The constriction of arterioles increases resistance, which causes a decrease in blood flow to downstream capillaries and a larger decrease in blood pressure.

Detailed explanation-4: -vasoconstriction: constriction of the smooth muscle of a blood vessel, resulting in a decreased vascular diameter.

Detailed explanation-5: -Vasoconstriction is the narrowing or even closing of the lumen of a vein, artery, or arteriole as a result of smooth muscle cell constriction in the blood vessel wall. By reducing the diameter of a blood vessel, circulating blood must move through a smaller area under higher pressures.