Muscular



The muscular system is an essential part of the human body. Without this unique system, several important organs would shut down, all movement of the body would stop, and eventually leave you dead. Muscles are a band of fibrous tissue that connect to bones. They have the ability to relax and contract, producing movement. There are two types of muscles. They are called Voluntary muscles and Involuntary muscles. The difference in these two muscles comes from the fact that you can move Voluntary muscles, but not Involuntary muscles.

The primary function of the muscular system is simple. The muscular system moves the human body through a variety of several different ways of moving several different organs.The cardiac muscles move the heart, forming the tissue in the heart called the docardium. Skeletal muscles allow humans to make movements that are essential to everyday life, such as picking up things and walking. Abdominal muscles and the muscles in the lower back protect organs from danger that could harm them severely. Smooth muscles that res ide in the stomach and intestines help digest food by moving the food down the digestive tract. Smooth muscles also force blood through the many blood arteries in the human body. Skeletal Muscle Fibers help skeletal muscles move. All of these different things are essential in this important system.

__//Muscle Fibers//__
Skeletal Muscle fibers are bundled together into large tube like packages called fascicles. The muscle fibers (myofibers) are long, circular cells made of actin and myosin moyfibrils. These muscle fibers have more than one nucleus so that they can make the protein that they need. The cytoskeleton inside the muscle fibers allows the  muscle fibers to contract and relax again. There are lots of mitochondria in muscle fibers. These are necessary to provide cellular energy that allows movement. Muscle fibers are very important.
 * //Red Muscle Fibers -// Red Muscle Fibers are fibers containing high levels of myoglobin and oxygen storing proteins have a red appearance. These fibers usally have more mitochondria and blood vessels than the white fibers.
 * //White Muscle Fibers -// White Muscle Fibers have a lower content or mitochondria and blood vessels than Red Muscle Fibers. This gives them a white color.
 * //Slow Twitch Muscle Fibers -// The slow twitch fibers generate energy for ATP re-synthesis. Most of the time they have a low movement level of ATP, a slow speed of contraction, with a not so well developed glycolytic capacity. They contain a vast amount of mitochondria and the high levels of myoglobin that gives them a red color. They have been known to have high concentration of mitochondrial enzymes, which makes them fatigue resistant.
 * //Fast Twitch Muscle Fibers -//Some people describe a fast twitch fiber as one that the myosin can split ATP quickly. However, fast twitch fibers also have a higher capability for electrochemical transmission of action potentials, and have a **rapid** level of calcium release. The fast twitch fibers depend on a well developed glycolytic system for energy transfer and can contract and develop tension at 2-3 times the rate of slow twitch fibers.
 * //Type One Muscle Fibers -// Type one muscle fibers fatigue slowly and provide greater endurance.
 * //Type Two Muscle Fibers -// Type two muscle fibers, otherwise known as anaerobic muscles, produce rapid action and fatigue more quickly than other muscle fibers.

//__Types Of Muscles__//

[[image:muscle_anatomy.jpg width="364" height="242" align="left" caption="Anatomy of A Muscle"]]
Cardiac Muscles are a kind of straited muscle sorrounding the heart that forms the docadorium. These fascinating muscles form striations that have alternating thick and thin protein filaments. These muscles move the heart, pumping the blood through the body, as well as providing some protection to this vital organ. Because this is an involun tary muscle, humans can't control it, and that means that blood is always pumping. This is a truly essential type of muscles that humans just couldn't do without. Cardiac muscles are capable of contracting like skeletal muscles and also stretching like smooth muscles. Cardiac muscles are largely twitch muscles, which means it only shows short single contractions.

//Abdominal Muscles// are a thick type of muscle, and they protect several important organs throught the body from danger. I // Smooth Muscles // are in th e stomach and both intestines, and they exist so that the digestive system can digest the food. Smooth muscles also line the arteries in the body, and assist them by pumping blood through the veins. Smooth muscles are present in the body's internal organs like the digestive system and respiratory system. Smooth muscles are capable of stretching and also maintaining tension over a considerable period of time. These muscles are involuntary muscles. It means we do not have control over them and they are controlled directly by the body's nervous system.

//Skeletal Muscles// are all around the body, and they tighten and relax, moving muscles, and in turn, the body. They are attached to bones by groups of tendons (Collagen Fibers). These muscles are very important because they allow movement in the body, and without this essential function, we would remain immobile. The human body contains about 650 skeletal muscles. Skeletal muscles function in pairs - one makes the body part go in one direction while the other one gets it back again to the original position. These type of muscles are voluntary muscles. It means that when we think about moving the muscle, the message is transferred to the concerned muscle via the nervous system, which makes it contract. Short, long and single are the three types of contractions these muscles are capable of.

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While there are several different types of muscles, there are also many different individual muscles that are in different places and serve their own purposes. ======
 * //The Abdomical Muscles -// The Abdominal muscles are located in the stomach, and their major funnction is to allow postural alignment in the human body
 * //The Biceps -// The Biceps are located in the front of the upper arm, and their main function is lifting and pulling things.
 * //The Deltoids -// The Deltoids are located in the top of the shoulders, and they assist the body with overhead lifting of objects.
 * //The Erector Spinae Muscles -// The Erector Spinae Muscles are located in the lower back, and just like the Abdominal muscles, they help the human body with postural alignment.
 * //Gastrocnemius and Soleus Muscles - //The Gastrocnemius and Soleus Muscles are located in the back of the lower leg, and it assists the human body in walking.
 * //Gluteus Maximus - //The Gluteus Maximus is located in the buttocks.
 * //The Hamsting Muscles -// The Hamstring Muscles are located in the back of the thigh. Their primary function is to allow the human body to walk.
 * //Latissimus Dorsi and Rhomboid Muscles -// The Latissimus Dorsi and Rhomboid Muscles are located in the mid back and shoulder blades, respectively. They both work together to assist in postural alignment.
 * //Oblique Muscles -// The Oblique muscles are located in the side of the human body. Their main purpose is to allow flexibility and side flexion to occur.
 * //Pectoralis Muscles -// The Pectoralis muscles are located in the front of the upper chest. Their function is to give the body upper strength.
 * //Quadricep Muscles -// The Quadricep muscles are located in front of the thigh. They allow the body to have enough strength to propel itself.

All of the muscles in the human body are extremelly important because they all work together as a team. Sometimes several different types of muscles have to work together to do one function. As you can see, the muscular system is an essential part of the human body, and without it we could not survive.

__//**Fun Facts**//__
 * Forty percent of your body weight lies in muscles.﻿We have about 700 muscles in our bodies, thirty of which are facial muscles.
 * The busiest muscles in our bodies are the eye muscles, and they move around one hundred thousand times.
 * The largest muscle in the human body is the Gluteus Maximus.
 * The smallest muscles in the human body are the ear muscles.
 * The longest muscle in the human body is the Starorious muscle.﻿Muscles can only pull, and they can't push.
 * Many muscles are attached to bones.
 * Shivering is caused by miniature muscle contractions.
 * Muscles can mend themselves over time with only minimal help.
 * There are muscles in the root of your hair that give you goose bumps.
 * It takes 17 muscles to smile and 42 muscles to frown.
 * There are 20 muscles in each hand.﻿It takes 200 muscles to take a step.
 * The busiest muscles in your body are the eye muscles, which move approximately more more than 100,000 times in a day.
 * There are muscle cells in the longest body muscle which are more than a foot in length.
 * Muscles in the middle of the ear are the smallest muscles present in the human body.
 * Masseters or chewing muscles are the strongest muscles in the body.
 * Muscles have about 640 individual names and require food and oxygen to function properly.
 * Starorious is the longest muscle in the human body.
 * Most of the muscles in the human body are attached to bones.

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