Fill in the Blanks Level 3 Facial - The Academy - MusclesOnline version Muscles by Jenny Storey 1 There are almost muscles in the body , which can make up almost half of your body weight . Muscles have three main functions : ? ? Maintaining ? Production of heat The muscular system is also involved in the movement of such as ; ? Blood ? ? Urine Muscles play a part in order to stand upright , the fibres of some muscles create and rigidity . Heat is created by the movement generated by the muscles . Each muscle is approximately 75% , 20% protein and 5% mineral salts , glycogen and fat . Skeletal muscles are composed of bundles of muscles fibres called . These bundles and muscles are surrounded by connective tissue sheaths . The epimysium is the outer layer which encircles the entire muscle . The perimysium surrounds collective bundles of muscles , whilst the surrounds the individual muscle fibre . This layer contains blood capillaries that supply blood containing oxygen and nutrients , and remove waste products . The three main types of muscle are voluntary , which is mainly attached to the bone , , which is found inside the digestive and urinary tracts as well as the walls of blood vessels , and finally cardiac , which is only found in the walls of the heart .
New game