Final answer:
The word for decreasing the size of the diameter of a vessel is 'vasoconstriction,' which increases resistance to blood flow, especially significant in conditions like arteriosclerosis.
Step-by-step explanation:
Building a word that means decreasing the size of the diameter of a vessel is vasoconstriction. Vasoconstriction refers to the narrowing of the blood vessels resulting from the contraction of the vascular smooth muscle. Vascular tone is a primary determinant of a vessel's diameter and hence of its resistance and blood flow. A decrease in the diameter of a vessel increases the resistance to flow since the resistance is inversely proportional to the radius of the vessel raised to the fourth power. This concept is highly significant in medical conditions such as arteriosclerosis, where plaque accumulation can constrict an artery, dramatically reducing blood flow. An example problem could involve calculating the percentage decrease in the diameter of a coronary artery based on the observed decrease in blood flow rate due to arteriosclerosis.
The word for decreasing the size of the diameter of a vessel is vasoconstriction. Vasoconstriction refers to the narrowing or tightening of blood vessels, which decreases their diameter. This process is controlled by neural and chemical signals that regulate the contractile state of the smooth muscle in the vessel walls. Vasoconstriction increases resistance and decreases blood flow through the vessel.