THE HUMAN BODY UNIT 3 THE LOCOMOTOR SYSTEM

THE HUMAN BODY UNIT 3

THE LOCOMOTOR SYSTEM bones • short • Long • Flat ribs They protect internal organs and support the body. • Voluntary muscle biceps/triceps s • Involuntary • Fixed • Semi-flexible joints vertebrae • Flexible elbow They move bones when they contract and relax. They join bones together and help make the skeleton flexible.

B O N E S Short: provide support and stability. In our backs, hands and feet. Flat: protect our internal organs. Our ribs. Long: are used for movement. In our arms and legs. J O I N T S Fixed: do not move. Semi-flexible : allow a little movement. Flexible: allow a lot of movement. M U S C L E S Voluntary: are controlled by our brain. Involuntary: move automatically.

The skeleton is made up of all the bones and cartilage in our body. Bones are made of hard bone tissue. Cartilage is made of a more flexible tissue. maxilla mandible Short: provide support and stability. In our backs, BONES hands and feet. Flat: protect our internal organs. Our ribs. Long: are used for movement. In our arms and legs. patella

Joints Our bones are connected at joints. Flexible cartilage protects the end of these bones. J O I N T S Strong elastic bands of tissue called ligaments connect bones at a joint. Fixed: do not move. Semi-flexible : allow a little movement. Flexible: allow a lot of movement. A fracture is a broken bone. A sprain is when we tear a ligament. A dislocation is when a bone is moved from its normal position in a joint.

Muscles There are over six hundred muscles in the human body. intercostals Muscles help to: • Give our bodies shape. • Move. • Protect our internal organs. Muscles are made up of muscle fibres and the muscles in our body respond to the nervous system by contracting and relaxing Tendons tissues which connect muscles to bones. The musculoskeletal system is made up of bones, ligaments, muscles and tendons. Voluntary: are controlled by our brain. Involuntary: move automatically.

The nervous system central nervous system The nervous system receives and responds to information from the five sense organs. It controls the working of the internal organs and body systems, such as the circulatory and respiratory systems. It produces reflex actions that protect our bodies from danger. Cerebellum: controls balancem movement Brain stem: Cerebrum: and connects the biggest coordination. brain to the part and spinal cord controls and controls voluntary involuntary movements. 1. movements. BRAIN The control centre 2. - SPINAL CORD: is made up of nerve tissue and runs from our brain down our spine. It controls reflex actions. Peripheral nervous system Our nerves are made up of nerve cells called neurons. They are connected by tiny branches.

The nervous system and the senses Our sense organs detect information from the environment and neurons transmit this information to our brain. Sight Hearing Smell Taste Touch Can detect colour, shape and size. Can detect loud, soft, high and loud sounds. Can detect chemicals – pleasant or unpleasant in the air. Can detect tastes – bitter, sweet, sour, salty Can detect temperature, texture, pressure and pain. • Cornea • Pupil • iris • lens • retina • Nerve receptors – Optic nerve • eardrum • three small bones • cochlea • auditory nerve • nostrils • Nerve receptors – Olfactory nerve • taste bud • epidermis • dermis