This is one of the 3 main muscle stuctures of the human body
Others are as follows
- Cardiac Muscle
- Skeletal Muscle

Smooth muscles are a non-striated muscle.

The control of smooth muscles is done by the “autonomic nervous system” which allows for
involuntarily control. This means that you may not consciously control these muscles.
Hormones may be released that can affect smooth muscles in some cases.

Smooth muscles are found in several areas such as:

– Large arteries
– Small arteries
– Veins
– Bladder
– Respiratory tract
– Gastrointestinal tract
– Eyes (some aspects)
– Uterus
– Kidney
– and others.

There is a large difference between smooth muscle and skeletal or cardiac muscle.

Smooth muscle can contract and relax. There are 2 types of arrangements of muscle
cells

1.) multi-unit
2.) single-unit

Single Unit is much more common and refers to the visceral smooth muscle because
it is often found on the “viscera” (eternal organs) of the body including intestines

Multi Unit are specific fibers that are activated by a nerve fiber, usually its own.
They can be found to line the large airways and large blood vessels.

Smooth muscles have a single nucleus and several mitochondria
Within the cytoskeleton of proteins is myosin and actinare proten filament. This is the action process of the muscle.
However, smooth muscle does not contain troponin like skeletal and cardiac but
rather calmodulin.

ATP continues to be very important for contraction of smooth muscles.

The function of smooth muscle is to maintain the dimensions and structure of organs and other
areas. When the organ may need to contract or function – smooth muscles allow for this function.