Skeletal Muscle

Definition of Skeletal Muscle

Skeletal muscle is a special kind of contractile tissue, present in all animals. It controls the movements of the body. This particular muscle consists of a bunch of muscle tissues with a protective membrane covering them. 

The skeletal muscle tissue function enables humans to perform all sorts of physical activities through its continuous contraction and expansion. 

Let’s proceed with skeletal muscle structure and function in details!

Structure of Skeletal Muscle

The structure of skeletal muscle is divided into several parts. The fundamental unit of this muscle is multinucleated muscle cells. Primarily a tendon connects a skeletal muscle with a bone so that mammals can move their body parts freely. This tendon directly links to the outer layer of muscle, or epimysium. 

Under the epimysium, there are fascicles which are groups of muscle fibres. Again a collagen-based protective layer covers them. Another component of skeletal muscle is perimysium which let the intricate blood vessels and nerves slip into the muscle. As a result, blood flow increases. 

The following skeletal muscle diagram will elucidate all the vital parts of it.

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Kinds of Skeletal Muscles

There are mainly two types of skeletal muscles present in human anatomy, Fast twitch and Slow-twitch muscles. 

  1. Fast-Twitch - These skeletal muscle fibres produce a high flow of energy and speed for a short while. For example, anaerobic respiration. However, they tire quickly. 

  2. Slow-Twitch - This variant of skeletal muscles can effectively supply energy for a longer period. For instance, they are responsible for holding posture like keeping their head upright. Also, marathon runs like endurance exercise takes place because of these muscles. 

Question: What are the other kinds of skeletal muscles? Also, make a table based on the difference between Red and White muscles. 

Skeletal Muscle Location

Among the structural classification of muscles, skeletal ones are of utmost importance because they are plenty in numbers and scattered throughout the whole body. Majorly they situate between bones, in hearts as cardiac muscles, in biceps, triceps, hamstrings and other places. Also, animals like mussels, crabs and other species with exoskeletons have these muscles. 

Now you can prepare an ultrastructure skeletal muscle note. Along with that draw a clear diagram and let your biology teacher check it for you. 

Skeletal Muscle Functions

Skeletal muscles perform several functions depending on its location. For example, when you throw a ball, a lot of actions take place within the skeletal muscle. These include –

  • Movement of Body - Skeletal muscle function is hugely accountable for the body movements like singing, playing, dancing and others. The tendons attached to these muscles pull the organs closer or further making these activities possible. 

  • Protects Organs - These muscles act as a protective barrier that guards the inner organs of the body against external shocks and attacks. 

  • Maintains Posture - This particular type of muscle retains the variable postures of the human body. For example, Sartorius muscles, along with other core muscles, instigate walking.  

  • Works as Hinges - The unique structure of skeletal muscle lets it work through contraction and release of muscle tissues. It regulates the opening and closing of several organs like urinary tracks, mouth, etc. This process makes urination and swallowing food possible, respectively.  

Besides, you should know that one of the excellent properties of skeletal muscle is that it measures almost half of an animal’s body weight. As a result, numerous chemicals target it and leave an adverse effect on the body like body ache, sprains, etc. 

For more information about what is skeletal muscle in other animals than homo sapiens, check the study materials available on our website now! You can also install the phone app for easier access to the course materials.

FAQ (Frequently Asked Questions)

1. What are the Four Main Functions of Skeletal Muscle?

Ans. The four primary functions of skeletal muscle are- 1) helps in movement, 2) maintains a proper posture of the body, 3) generates energy and heat for the body, 4) protects inner organs of the body.

2. Why do Skeletal Muscles Called Striated Muscles?

Ans. Skeletal muscle appears as alternative black and light bands or stripes under a microscope. Hence, they are synonymous with striated muscles.

3. Name the Muscles Which are also Called Skeletal Muscle.

Ans. A few names of skeletal muscle are Biceps brachii, Anconeus, Pronator teres, Palmaris Longus, etc. All of them are parts of human anatomy.