Muscles, skeleton and skin give the body shape and form. But it’s the muscle tissues that clearly give the features and shape of the human body. Much effort is given to muscles that it has even become a large global industry just to maintain it.
Among the specialized tissues in the body, the muscle tissue is highly specialized. Muscle tissues have contracting abilities and conducting abilities. Muscles are found to carry out electrical impulses. Voluntary muscles are differentiated from involuntary muscles. In terms of structure, muscles can either be striated or smooth. Muscles are commonly known as smooth, skeletal and cardiac.
Different organs use different kinds of muscles. Small intestines have smooth muscles. Smooth muscles are neat and form parallel lines. Intestine muscles are involuntary muscles. They contract without conscious thought. These muscles fit the intestines because digestion is not an act of will. Whether you like it or not, intestines will move according to the contents of your stomach either when they are full or empty. The uterus also has smooth muscles. Other organs such as the bladder, blood vessels and other internal organs also have involuntary muscles.
Skeletal muscles are confused to be fibres of connective tissues. Skeletal muscles are not of connective tissues because these muscles are not extracellular elements. These muscles describe the individual skeletal muscle cells. These tissues are fibres that are thin and very long. They almost look like threads like the one we see in clothing. Under the microscope, these cells are cylindrical and unbranched. The nuclei of these tissues are neatly arranged that goes around the periphery of the cell.
This neat and orderly arrangement is made up of actin and myosin filaments found inside the muscle cell. Skeletal muscle cells that are arranged and form large bundles are called fascicles. These bundles are enveloped with thin layers of connective. Continuous arrangements of these fascicles become parts of a particular muscle organ, for example biceps.
Cardiac muscles are almost an integration of smooth muscles and skeletal muscles. These muscle tissues make up the wall of the heart. They are striated and multinucleate like skeletal muscles however, they also seem to be smooth because their nuclei are located at the center and that a lot of cells are required to occupy the length of the muscle.
“It differs from both skeletal muscle and smooth muscle in that its cells branch and are joined to one another via intercalated discs. Intercalated discs allow communication between the cells such that there is a sequential contraction of the cells from the bottom of the ventricle to the top, facilitating maximal ejection of blood from the ventricle during contraction. This occurs with out nervous innervation to each cell or group of cells. Cardiac muscle also differs from the other two muscle types in that contraction can occur even without an initial nervous input. The cells that produce the stimulation for contraction without nervous input are called the pacemaker cells.” (Ackerley, 2006)
These three types of muscles help the body more than make it look good. There are many important benefits from proper maintenance of muscle tissues. The muscle is fit when one is strong, has endurance, is flexible and can carry out everyday tasks without injury. Keeping the muscle fit will also keep the organs fit. Programs such as weight lifting or weight bearing help the muscle build endurance and flexibility.
One need not be a weight lifter to have properly maintained muscles. Weak muscles are cause of lower back and posture-related diseases that can lead to painful problems. If the muscles are healthy, it will help the skeletons to cope up with stressful activities of the body.
Both voluntary and involuntary muscles are important to keep the body balanced. Massaging muscle tissues are almost the basic human instinct that is first aid to muscle pains. Massaging the muscles specially the ones that are in pain or are with disease is a way to increase body chemical flow in and out of the muscles. Given that muscles are smooth, skeletal or cardiac, massaging the muscles will help the muscle tissues from stagnating and being rigid.
Ackerley, Sandra K. 2006. Muscles. Department of Zoology, University of Guelph, Guelph, Ontario, Canada. Retrieved April 1, 2006 <http://www.uoguelph.ca/zoology/devobio/210labs/muscle1.html>
Bourne, GH. 1960. The Structure and Function of Muscle. Academic Press