Any circulatory system has three general components as follows:

• Vehicle
• Conduits
• Motive forces

Vehicle
The vehicle is a fluid (flowing) medium. The materials being carried are dissolved or suspended in this fluid.

This is the blood, lymph, or cerebrospinal fluid.

Conduits
Conduits are like pipes.

They contain the fluids in which materials are transported to and from the various parts of the body.

These are the blood vessels or lymph vessels.

Motive Forces
Motive forces act upon the vehicle to make it flow through the conduits.

In the cardiovascular system these are provided by the heart.

Extra information screen
Some examples of circulatory systems of the human body include:

• the cardiovascular system

• the lymphatic system

• the CSF (cerebrospinal fluid) system

The lesser systems include:

• the aqueous humor of the bulbus oculi (eyeball)

• the endolymph and perilymph, which are fluids of the inner ear

This course focuses on the cardiovascular system.