Definition
The muscular system of a human body is the system of organs (muscles) that is responsible for any type of body movement (Muscolino 35). Muscles, of which the titular system is composed, are the tissue that is made of fiber and tissue and can contract and relax (Muscolino 38). The muscular system incorporates not only the skeletal muscular tissue but also the blood vessels, nerves, and tendons, of which muscles are built.
Anatomy
The muscular system is attached to the skeletal one, constituting the locomotor, or musculoskeletal, system (Kisia 110). The number of muscles that it includes exceeds 600, yet the existing classification system allows identifying the key ones (Kisia 112). As a rule, three types of muscles are typically identified:
Visceral
Also known as the smooth tissue, the said type of muscles is typically associated with the internal organs, in general, and the ones located in the abdominal cavity, in particular (Kisia 116). Visceral muscles are also known as smooth (because of their uniform structure) and involuntary (because it is controlled unconsciously by the human brain) (Kisia 119).
Cardiac
The cardiac muscles are located only in the heart and serve to sustain the blood flow (Kisia 115). The muscle is controlled intrinsically, which is why it is traditionally defined as autorhythmic (Kisia 115).
Skeletal
The identified type of muscle is the only one in the musculoskeletal system that is controlled on a conscious level by the human brain (Kisia 118). The tendon that connects the muscle to a bone allows for the contraction of the former and, therefore, the movement of the body. The examples of a skeletal muscle include the biceps brachii, the triceps brachii, the anconeus, etc. (Kisia 119).
Functions
As the definition provided above shows, the movement of the body is the primary function of the muscular system. Furthermore, stability and posture should be mentioned among the characteristics of the human body that the muscular system sustains.
However, the identified function of the muscular system is not the only one. Additionally, the system serves as the means of maintaining posture and allows for blood circulation (Muscolino 74). In other words, while the system is typically associated primarily with lifting a weight, it allows performing a variety of movements as well, not to mention the fact that it helps sustain blood flow. The identified function is performed by the cardiac muscles.
Furthermore, the support of the digestive system can be considered an essential function of the musculoskeletal one. The smooth muscle, which constitutes a range of organs in the digestive system, lines the walls of the stomach. Consequently, when the muscle contracts, the digestive process occurs.
Additionally, the system is also known for helping the human body to produce heat. The identified phenomenon occurs after a movement takes place, therefore, making it possible for the body to function. The production of heat is especially important in the low-temperature environment. Thus, the blood circulation is kept at the required rate even in the cold environment.
Diseases
Traditionally, when considering muscular diseases, one mentions inflammatory myopathies as the most common type of muscular disease. The identified condition triggers the weakening of the muscles. Dermatomyositis, which also implies that muscles should experience inflammation, is followed by a skin rash. Finally, muscular dystrophies should be listed among common muscular disorders (Kisia 121).
Works Cited
Kisia, Steven M. Vertebrates: Structures and Functions. CRC Press, 2016.
Muscolino, Joseph E. The Muscular System Manual – E-Book: The Skeletal Muscles of the Human Body. Elsevier Health Sciences, 2016.