This chapter discusses skeletal muscle since, as its name suggests, it is directly or indirectly attached to the bones of the skeletal system by bands of fibrous connective tissue called tendons. It shows that the edges of the skull bones don't completely ossify until much later to allow for moulding of the head during birth and expansion as the child grows. The chapter suggests that the bones of the cranium do not completely fuse together until the child reaches 12–18 months old and that it is still possible to feel the anterior fontanelle during this time. The muscular-skeletal system consists of muscles, bones, cartilage, tendons, ligaments and other connective tissue that helps to stabilise and support the skeleton. Skeletal muscle is the most abundant type of muscle in the body and accounts for about 40% of total body weight. The skeletal system accounts for about 20% of total body weight and consists of 206 bones of varying shapes and sizes.