19 Mighty Muscles

Mighty Muscles written by Samantha Montgomerie

what are muscles? Trapezius Deltoid Pectoralis major Serratus anterior Biceps Linea alba External abdominal oblique Rectus abdominus Tendinous inscription The human body has more than 600 different muscles. All of these muscles make up the body's muscular system. These muscles help us to do many things. We use our muscles every time we move. Sometimes we think about moving our muscles. We do this when we use them to lift heavy things. Some muscles also work without us having to think about them. They can help to pump our blood. Our heart is a muscle that works to pump blood around the body.

how muscles work Skeletal muscle Cardiac muscle Smooth muscle Muscles have thin cells that are in bundles. Our brains or bodies tell them when they have to move. They contract or relax, pulling our bones. They can also work in pairs to move parts of the body. One muscle will contract and the other will relax. There are three different types of muscles in the human body. Skeletal Muscles, Smooth Muscles and Cardiac Muscles. These all do different jobs.

skeletal muscles Skeletal muscles cover our bones and move our skeletom These are the muscles that show how strong we are. These muscles give our body power. They help us to be quick and able to lift heavy things. We can control what we want these muscles to do. These are called voluntary muscles. If we want to kick a ball, we are able to make our leg do this. If we want to lift our backpack, we can make our arm do this.

smooth muscles Smooth muscles work the organs in our bodies. These work on their own and are called involuntary muscles. Our brain tells these muscles what to do without us even thinking about it. Smooth muscles help to push food through our body. They help our eyes to focus and make the hair on our bodies stand up when we are cold.

cardiac muscles Muscle Tissue Heart Cardiac Muscle Muscle cells The cardiac muscle is the muscle that makes up the heart. Like a smooth muscle, it works without us thinking about it. It works hard to keep our heart beating quickly. It beats 60 to 100 times a minute. The cardiac muscles work like a pump. They contract to pump and push blood through the heart. They pump blood into the rest of the body then relax to let the blood back into the heart.