The Muscle system BY EWEN MUNRO AND STRUAN

The Muscle system BY EWEN MUNRO AND STRUAN CAIRNS

The muscular system • There are 639 muscles in the human body • At the end of each muscle is a tendon which attaches muscle to bone. • Each muscle has an origin and insertion • The origin is fixed, the insertion moves. • The muscle system is made of 6 trillion fibres – each thinner than a human hair • A fibre can support 1000 times its own weight.

What is muscle • Muscle is a soft tissue found in animals and humans • Muscle cells contain proteins that slide past one another, producing a contraction that changes both the length and the shape of the cell, which gives movement • Muscle tissues are made from cells in a process known as myogenesis. • There are three types of muscle, skeletal, striated, cardiac (your heart), and smooth.

An individual muscle • Skeletal muscle is made of: Ø muscle cells – fibres, Ø connective tissue – facia Ø nerves and blood vessels • Like an orange segment – facia encloses the muscle

Types of skeletal muscle • • • Flat muscle (abs) Triangular (shoulder blade) Fusiform (biceps) Strap muscle (legs) Unipennate (shins) Multibennate (shoulder)

Functions of a muscle • All muscles can contract and relax • Gives elasticity and power to move • Muscle contains blood vessels to supply food and oxygen • Muscles contain nerves which stimulate the tissue and send messages to the brain

Why we need muscle • • • We could not move without them We could not stand without them They keep us alive They protect our bones They make us strong