Our bodies move because our brain tells different parts of our body to do stuff and then our body listens.
But in order for our bodies to move with these instructions, our bodies must consist of certain features such as bones, joints and muscles.
These different features help our bodies to move and to do things that we do on a daily basis.
If you tell your body to pick up a gallon of milk and hold it over your head, your body will do that, but how? Muscles help us to do things such as lifting, sitting and everyday things that you do.
One great thing about muscle function is that we do not have to tell our muscles to work, they just do.
Your body has over 600 different muscles and most of these are called skeletal muscles. Skeletal muscles are muscles that are attached to the bones and these types of muscles help us to do voluntary movements, which are movement that we can control.
Skeletal muscles are attached to our bones and these are attached with tendons. Tendons are tissue that is strong, and it connects to the bones so that our bones can help the muscles to move.
One interesting fact about muscles is that they can only pull and not push, so oftentimes, muscles are forced to work in pairs in order to make our bodies to move correctly.
An example of this is your arm. In order to raise your forearm, your bicep muscle contracts and at the same time, your triceps muscles that are located on the back of your arm relaxes.
With this pair working together, the muscles help you raise your arms. Many other muscles work together in order to make movement happen.
There are many different muscles that work together to move your eyeball.
Because our eyes can move up, down, sideways and more, there are muscles that are attached to the top, bottom and side of the eyeball and the other end is attached to the bone in the eye socket.
These muscles in your eyes are involuntary muscles, and you will learn what involuntary means below.
Most of the time when we think of muscles, we think of ones that move our bones. There are other muscles that move other parts of your body.
Muscles in the stomach and in the intestine have muscles called smooth muscles.
Smooth muscles are muscles that contract or move involuntarily such as when you swallow food and it moves through your digestive system.
Another type of muscle is a cardiac muscle. Cardiac muscles are located in your heart and these muscles contract so that blood can pump through the heart.
The cardiac muscles are also involuntary muscles.
Remember, voluntary muscles are ones that you control, and involuntary muscles are ones that your body does for you.
Your brain tells these muscles to move and your body is not even aware that your body is using these muscles.
Sometimes, muscles are arranged in bundles. Muscles that are arranged in bundles are called striated (striped) muscles.
There are also threadlike structures that are found in the muscle fiber and these are called myofibrils. The basic functional unit of a muscle is called sarcomere.
The explanation of how muscle fibers contract are called the Sliding Filament Theory.
The Sliding Filament Theory tells us how muscles can only move one way and how muscles work with actin and myosin to form a bridge movement that helps muscles contract.