The function of smooth muscle differs from other muscles. However, smooth muscle has an equally important function in the body. This cellular tissue that is part of the body’s anatomy has a particular shape.
Muscles are the most important part of the human body. There are various types of muscles with their respective roles.
The existence of this muscle serves to help humans make movements. The bones of the body cannot move without muscle.
Muscles can also move vital organs in the body to function properly. Well, one type is smooth muscle.
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It turns out that this is the function of smooth muscle!
In contrast to the skeletal and heart muscles, smooth muscle in the human body has a fairly special anatomy.
This muscle functions including the involuntary type of muscle. This means that smooth muscle will function reflexively. Of course, this muscle is also made up of extraordinary cells.
The cell has a simple spindle-like shape with a pointed or pointed end on a nucleus.
The actin and myosin in the smooth muscle will move, triggering the contraction. Furthermore, smooth muscle also contains tropomyosin but without troponin.
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The important role of smooth muscles in the human body
The role or function of smooth muscle is quite varied. This will depend on where they are located.
First, the smooth muscle in the womb will work to help the baby’s birth process. This smooth muscle will push the baby out of the womb.
While the smooth muscle in the bladder serves to help expel water. If in the blood vessels, smooth muscle will help in the circulation of blood flow in the arteries.
So smooth muscle is also found in the digestive tract. Here, smooth muscle works to move food. Meanwhile, in the eye, the task is to help the pupil shrink after the observation process.
There is also smooth muscle tissue in the lungs to regulate airflow and also expand the contact that the lungs need.
This muscle is also in the veins and testicles. The veins work to regulate blood pressure and the testicles to regulate ejaculation through the contraction of the sphincter muscles.
Smooth muscle structure
To perform the function of smooth muscles, they also have their own structure. Smooth muscle tissue with a single unit or a single unit is part of the muscle in the form of fibers.
The muscle will then contract with the cell membranes attached to each other. Therefore, this smooth muscle does not require the contraction of the external nerve.
Generally, this smooth muscle is found in the hollow organs or viscera. However, there is also smooth muscle which has a multi-unit structure.
This type of smooth muscle with this structure is present in the trachea, iris and elastic arteries. Smooth muscle with a different fiber structure will work alone or not to help each other.
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How smooth muscles work
Smooth muscle function works by contracting. The actin and myosin filaments contract and interact with each other.
The contraction will be activated with the help of calcium ions and ATP or adenosine triphosphate. Therefore, energy will appear in the contraction process.
Actin filaments in smooth muscle are generally smaller in diameter than myosin filaments. The number of actin filaments is also greater, which is about 15 times the number of myosin.
As a result, actin filaments will be seen more often in a muscle slice than these myosin. Smooth muscle has a working mechanism that does not follow the commands of the brain.
That is, this muscle will either work or contract reflexively or unconsciously, which makes it an involuntary (autonomous) muscle. The functioning of this smooth muscle will work slowly but continuously.
Smooth muscle will work tirelessly on parts of the body such as the urinary tract, uterus, eyes, and many more.
In addition, the function of smooth muscle in the body is very effective. Two thirds of the length of the stroke can be contracted at most. (R10 / HR-Online)
