What substances increase blood flow into a capillary bed?

The vasodilator substances produce local dilation of blood vessels and relaxation of precapillary sphincters. The result is the increase in blood flow to the tissue, organ, or region which increases the oxygen level.

Vasodilation. Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins (called venodilators), large arteries, and smaller arterioles. ... Endogenous substances and drugs that cause vasodilation are termed vasodilators.

you must remain stopped until the stop signal is retracted and the red lights are turned off. approaching traffic in the opposite roadway of a divided highway shall not be required to stop, even if the school bus has the stop-arm extended and the alternately flashing warning signal lamps on.

clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.