Arteries, veins, capillaries

What is the function of arteries?

Carry oxygen-rich blood from the heart to the body (except pulmonary artery).

What is the function of veins?

Carry oxygen-poor blood back to the heart (except pulmonary veins).

What is the function of capillaries?

Facilitate gas exchange (oxygen and carbon dioxide) and nutrient/waste exchange between blood and cells.

What is the pressure in arteries?

High

What is the pressure in veins?

Low

What is the pressure in capillaries?

Very Low

What is the lumen diameter of arteries?

Narrow

What is the lumen diameter of veins?

Wide

What is the lumen diameter of capillaries?

Very narrow

What is the wall thickness of arteries?

Thick

What is the wall thickness of veins?

Thin

What is the wall thickness of capillaries?

Very thin

How many wall layers do arteries have?

Three

How many wall layers do veins have?

Three

How many wall layers do capillaries have?

One

How much muscle & elastic fibers do arteries have?

Lots of smooth muscle and elastic fibers

How much muscle & elastic fibers do veins have?

Less smooth muscle and fewer elastic fibers

How much muscle & elastic fibers do capillaries have?

No smooth muscle

Do arteries have valves? If yes, what is the function?

No

Do veins have valves? If yes, what is the function?

Yes, to prevent backflow and ensure blood flows toward the heart.

Do capillaries have valves? If yes, what is the function?

No