Basically, the heart is a muscular pump that maintains oxygen and blood circulation through your lungs and body.

The digestive tract is simple and tubular, since the animal feeds entirely on blood, although the mouth is somewhat modified as a muscular pump.

The haemolymph is circulated to the appendages unidirectionally with the aid of muscular pumps or accessory pulsatile organs which are usually found at the base of the antennae or wings and sometimes in the legs.

The continual rolling causes blood to circulate-it uses a form of gravity feed system instead of a muscular pump.

Help your heart:The heart is a muscular pump and, just like the muscles in your arms and legs, it needs regular exercise.

Not the seat of the soul, but merely a muscular pump, unendowed with any more mystical purpose than the lungs or the kidneys.

The heart is a muscular pump made up of four chambers .

In a few cases, however, muscular pumps analogous to a heart are found in various parts of the system.

The orig-inal life-form had used a gravity feed system for circulation rather than a muscular pump, which was why they died quickly when weakness, accident, or an attacking predator caused them to fall on their sides and stop rotating.