Greetings to all and sundry on this platform once again. As a biochemistry student, today I researched "The Human Muscular System" and decided to share it with you guys here. I hope that you will enjoy it and also learn from it. Stay tuned with me as I discuss this topic in my article.
The human muscular system is a system that is comprised of a collection of complex tissues with specific functions. We need to understand the muscular system including the functions of these complex structures in order to understand the principle behind our movement and other physical movements. Let's generally look at some of the functions of the muscular system.
Functions of the muscular system
The human muscular system helps in the movement of the body that is locomoting from one place to the other. It is also responsible for the maintenance of the human body posture. It also helps during contractions and relaxations of the diaphragm during the respiration process. Furthermore, this system also plays a vital role in communication that is the movement of the lips helps one to talk. Moreover, the muscular system is responsible for the production of heat in the body and this is termed thermogenesis. Constriction of organs and vessels is also a function of the muscular system as well as the regulation of the heartbeat.
Some Characteristics of Muscles
Elasticity: muscles have the ability to recoil to the original length after it has been stretched.
Contractility: muscles have the ability to become short and generate some pulling force.
Excitability: muscles have the ability to respond to stimuli.
Extensibility: this is the ability of a muscle that allows it to stretch to its original length.
Basically, there are three types of muscle and they are; skeletal muscle, smooth muscle, and cardiac muscle. '
Skeletal muscles are responsible for movement, posture, respiratory movements, and facial expressions. Smooth muscles are also responsible for regulating blood flow, constricting pupils, mixing food in the digestive tract, and also propelling urine. Lastly, the cardiac muscles are responsible for regulating the flow or movement of blood in the human body.
The Skeletal Muscle Structure
It has nuclei that are peripherally located. Also, it has long fibers, which are cylindrical and multinucleated. It has a striated appearance and it is composed of connective tissues, nerves, muscle fibers, and blood vessels.
The Smooth Muscle Structure
They are not arranged symmetrically when compared to the skeletal muscle (no sarcomeres). The cells are not striated and they have more actin than myosin. it has a single, spindle-shaped, central nucleus. The fibers in smooth muscle are smaller than those in skeletal muscle.
The Cardiac Muscle Structure
The cardiac muscle has striated fibers bit are branched. They can be found in the heart only and they form the myocardium, a thick layer. They are under the regulation of the endocrine system and involuntary. Some cardiac muscle cells are autorhythmic indicating that the fibers can contract spontaneously. The fibers are also joined by intercalated disks. Each cell found in the cardiac muscle has a single centrally located nucleus.