Skeletal Muscle Tissue

Skeletal muscle tissue is also extensible and elastic. Tissues that can be stretched are known as extensible skeletal muscle tissue and the type of tissue that can return to its original following shape after distortion is known as elastic skeletal muscle tissue. Through the fusion of individual myoblasts or early muscle cells, skeletal muscle tissue is developed. The result of the process of fission leads to a characteristic multinucleated structure. Because the cells are fused and also multinucleated, they form a structural component known as a syncytium. The nuclei present in the skeletal muscle tissue are oval and are located at the periphery of the cell. The nuclei of the skeletal muscle tissue cells are accompanied by their respective satellite cells between the external lamina and sarcolemma. 

Type I muscle fibres

Type I muscle fibres are also called slow oxidative fibres because they specialize in aerobic activity. Type I muscle fibres are usually small in size, contains a pretty high amount of myoglobin, and also by colour variation, Type I muscle fibres appear in red in fresh tissues. What is a muscle twitch in skeletal muscle tissue notes? A muscle twitch can be described as a single contraction of a muscle. Muscle twitching also got a regular name known as muscle fasciculation. As we know our muscles are made up of fibre, which is controlled by nerves. 

Any kind of simulation or damage caused to the nerve cells which control the muscle, that’s when a particular nerve may lead to twitching of muscle fibres. However in our body, the majority of the muscle twitches go completely unmonitored and cause any concern, but in some cases, some muscle twitches indicate a nervous system condition and you may need a doctor’s attention.

Type I muscle fibres usually tend to make up a slow-twitch ( also known as fatigue-resistant motor units ). For maintaining a proper posture, the muscles present in the deep back are also mainly made up of Type I slow oxidative fibres.

Type IIa muscle fibres

Type IIa muscle fibres are also known as fast oxidative glycolytic fibres. Through colour comparison, these Type IIa muscle fibres appear slightly larger than Type I muscle fibres usually present in fresh tissues. Type II muscle fibres also consist of numerous mitochondria and also have a higher myoglobin content than Type Ia muscle fibres. Unlike Type Ia muscle fibres, Type IIa muscle fibres carry a high amount of oxygen and glycogen in skeletal muscle tissue. Because of this continuous supply, Type IIa muscle fibres can carry out the process of anaerobic glycolysis and form fast-twitch, fatigue-resistant motor units. Type IIa fibres are comparatively more fatigue resistant than Type IIb fibres and are always used in particular movements that require high endured power

Many athletes, mainly competitive swimmers, have a high amount of these Type IIa muscle fibres present in their bodies. These fibres rely on anaerobic processes and are also responsible for the production of lactic acid, so they are not allowed to go as long as type I. Though Type IIa muscle fibres are given a very high capacity for generating ATP by the process of oxidative metabolic processes, and also split ATP at a very fast rate. Type IIa muscle fibres have a rapid contraction speed and also are much more resistant to type IIB fatigue.

Type IIb muscle fibres

Type IIb muscle fibres are also referred to by the name fast glycolytic fibres. Type IIb muscle fibres are large fibres that usually appear in the colour of light pink in particularly fresh tissues. Unlike Type IIa muscle fibres, Type IIb muscle fibres contain fewer quantities of mitochondria in them and also possess a lower amount of myoglobin than Type IIa muscle fibres. Although Type IIb muscle fibres, consist of low levels of oxidative enzymes but are unlikely to show much high-level anaerobic enzyme activity and also contain a particularly high amount of glycogen in them. But like in every type of muscle fibre, Type IIb muscle fibres also are much more prone to fatigue than type II, type IIa muscle fibres which make Type IIb muscle fibres go through fast Twitch, fatigue-prone motor units. Type IIb muscle fibres possess the fastest rate of ATPase activities and also are seen in skeletal muscle tissue used for short, fast bursts of contraction, for example, gastrocnemius, a muscle located in the leg that is used for jumping purposes.

Type IIb muscle fibres are recruited for power bursts such as maximal and also near-maximal lifting and performing short sprints. ATP formation in Type IIb muscle fibres is performed at a fast rate and has a quite fast contraction velocity present in them. Such fibres are found mostly in large numbers in the muscles of the arms.

Conclusion

The characteristics of muscle tissue are mostly categorized based on their only appearance and control over body parts such as either skeletal, cardiac, and smooth or visceral muscle tissue present performs function either voluntarily or involuntarily, and also seen in a structure as either striated or smooth. The main function of skeletal muscle tissue is being able to move by performing actions on the bones of the skeleton. It also pumps blood and gets the substances in motion all over the hollow organ systems. Skeletal muscle tissue engineering applications include:

1. Non-toxic biomaterial, diminishing products, or additives of biochemical products.
2. Non-allergenic biomaterial, diminishing products or additives of particular biochemical products.
3. Residues caused by biomaterial should be digestible.
4. The collagen scaffold should support the process of full maturation of fat tissue in vitro.