Muscular System - Meat on the BonesMany advanced animals have muscular systems. You know you do. Did you know that your muscular system is made up of three different types of muscular tissue? You have smooth, cardiac, and voluntary muscle tissue in your body. Smooth muscle is muscle you rarely control such as the muscle in your intestinal tract. Cardiac muscle is very specific tissue found in your heart. Voluntary muscle is the muscle that helps you move. All of those tissues add up to a muscular system that is found through your body. There is more to the muscular system than the muscles that help you move.
What Does This System Do?The big purpose of the muscles found in your body is movement. We could be talking about the movement of your legs while you walk. We could be talking about the beating of your heart. We could also be talking about the contraction of a very small blood vessel in your brain.
You have no control over most of the muscular system. You do control the voluntary muscle in your arms, legs, neck, and torso. You have little or no control over the heart or smooth muscle. Those other muscles are under the control of the autonomic nervous system (ANS).
Interacting with Other SystemsWe just teased the fact that your muscular system is closely connected to the nervous system. That makes sense since you usually have to think before you can move. Even though thinking is not always involved, the neurons of the nervous system are connected to most of the cells in your muscular system. You have smooth muscles that line your digestive system and help move food through your intestines. Smooth muscle also surrounds your circulatory system and lymph system. Those muscle tissues are spread throughout your body and are even involved in controlling the temperature of your body.
Muscles Help You MoveThe main parts of your voluntary muscular system include the muscles, and tendons. The muscle is called the meatus. It happens to be the meat you eat from cows, sheep, and includes the muscle in your biceps. So your bicep it the meat, that meat needs to connect to the bones so that you can move. Tendons connect your muscles to your bone at insertion points.
When the actin and myosin contract in the muscles, the muscle shortens and the bones are pulled closer together. Muscles called flexors force your joints to bend. Muscles called extensors cause your limbs to straighten. A bicep is a flexor and the triceps are extensors. You may have also heard of ligaments. They are batches of connective tissue that bind bones to each other. Muscles, tendons, and ligaments can been found working together in almost all of your joints.
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