One of the most important features of a living body is the ability to move. Movement helps us carry out various activities and complete different types of physical work. Movement is not only external, but also occurs internally. The beating of a heart is also a type of movement that helps keeps a body alive. Movement of the digestive system helps us digest food and give nutrition to the body. The reason our bodies can move is due to presence of muscles. Without muscles, we will be totally immobile like a plant. Muscles are divided into three types based on their structure. These include smooth muscle tissue, skeletal muscle tissue and cardiac muscle tissue. As we are talking about movement, this Bodytomy article will concentrate totally on skeletal muscle functions.
What are Skeletal Muscles?
Skeletal muscles are a type of striated muscle tissues. These tissues come under the somatic nervous system, and therefore are controlled by voluntary actions. They are also called striated muscles, somatic muscles or voluntary muscles. These skeletal muscles are made up of muscle fibers that are formed by fusion of myoblasts. The action and myosin myofibrils that make up these muscles give them the striated appearance. The muscle fibers running all the way from the point of origin to the insertion point of the skeletal muscles are bound together by a connective tissue. Through these connective tissues, blood vessels and nerves pass through. These muscle fibers contain myofibrils, mitochondria, smooth endoplasmic reticulum (SER) and many nuclei. The cells contain many nuclei because the myofibrils arise from fusion of many myoblasts. Thus, skeletal muscle fiber is also known as a syncytium. The skeletal muscle tissue cover the bones all over the body. They are attached to the bones with the helps of tendons or are directly connected to the rough bone patches. The arrangement of muscle fibers of the fascicles causes production of different types of skeletal muscles. These include the parallel muscles, pennate muscles, sphincter muscles and the convergent muscles. The skeletal muscles are under the control of the cerebral cortex.
Functions of Skeletal Muscle Tissue
Skeletal muscle contraction and relaxation leads to many body movement. These movements right from walking, holding, tilting your neck, blinking of eyes and many more are due to movement of skeletal muscle tissue. The skeletal muscle function and location makes it one of the most important tissues of the body. The skeletal muscle function includes 5 activities performed by these tissues. These functions are explained below:
Since the beginning of this write-up, I have focused on movement. Skeletal muscle contraction helps in pulling the tendons on the bones that causes movement. These movements include the extension of your arm, breathing, cycling, typing, writing, etc. The diaphragm, the important muscle for breathing helps a person not only to inhale and exhale, but also laugh, sneeze and cough. The deltoids in the shoulders help raise our arms above our head. The contraction of biceps and triceps helps in bending and unbending the arm at the elbow. The gluteal muscles help stabilize the hips for walking and running.
Posture and Body Balance
The skeletal muscles helps one maintain their body posture. For example, the gluteal muscle also helps one stand up and maintain the erect posture. The sartorius muscle in the thigh is the longest muscle in the body. This muscle along with four other muscles of the quadriceps help in movement of the leg. Not only that, they also help in maintaining the body balance.
Soft Tissue Support
The visceral organs and other internal tissues as well as organs that are very delicate are supported by the skeletal muscles. The abdominal wall and the pelvic cavity is made up of skeletal muscle tissues. These tissue not only support the weight of the internal organs, but also help protect them from a possible injury.
Help Support the Entry and Exit Points of Body
The various opening of the body, like the mouth, anus, urinary tract, etc. are covered by the sphincter muscles. These muscles are arranged concentrically around these openings. When these muscles contract, they opening gets smaller. Thus, they help in swallowing of food, urination as well as defecation.
Skeletal muscles help in maintaining body temperature as their contractions coverts energy into heat. Thus, after carrying out a strenuous activity one often feels very hot as the body releases heat due to the action of skeletal muscles system.
These were some of the skeletal muscle functions. As you can see, without skeletal muscles, our body will not be able to support itself and maintain posture. Each and every voluntary and in some cases involuntary movements, is due to the action of skeletal muscle tissue.