Capillaries and Precapillary Sphincters

Flashcards covering key concepts regarding capillaries and precapillary sphincters.

What is the function of the precapillary sphincter?

Regulates blood flow into the capillary bed at its origin.

What happens if all capillary beds open simultaneously?

They would hold every drop of blood.

Define capillary bed.

A small area where 10 to 100 capillaries are located to exchange substances.

What is a vascular shunt?

A bypass that occurs when precapillary sphincters are closed, shutting down the entire capillary bed.

What is Vasomotion?

The irregular rising and falling of pressure and flow in capillaries.

What is a pericyte?

A specialized cell wrapped around capillaries that connects the nervous system, brain, and vascular system.

What is the average lumen diameter of capillaries?

5-10 micrometers.

What type of capillary has a complete endothelial lining with tight junctions?

Continuous capillaries.

Where are fenestrated capillaries commonly found?

In the kidneys and small intestine.

Which type of capillary has the largest gaps and is found in the liver?

Sinusoid capillaries.