It helps the body function internally and externally as there are over 600 muscles in a human. These muscles are then broken down into groups known as smooth, cardiac and skeletal muscle. A smooth muscle is an involuntary muscle which we ourselves as humans have know control over. Each of the smooth muscle cell contains one nucleus, they are arranged in layers and usually found throughout the whole body where there are organs, glands and blood vessels. they are also found in the eyes for when we focus and to help the process of urination in the bladder. Cardiac muscle (myocardium) is also involuntary and hence the name it is found in the heart. This muscle helps circulate blood through the body and helps pump the heart allowing the heart to relax and refill. Skeletal muscle is a voluntary muscle which means we have control over it by conscious thought. When the body moves the muscles will work together (antagonistic) to either relax or contract but not both. The muscle will look striped which are called striations which are organised patterns of proteins. The attachment these muscles have to the bone are held together by tough tendons, the only skeletal muscle that doesn't are the facial muscles which allows the face to make expressions. Skeletal muscles will also control body temperature where the heat is produced by muscle