MUSCLES AND BONES The musculoskeletalm system is composes of many muscles and bones Humans have got an internal skeleton. It is made of 206 different bones The functions of the skeleton:► It suports the body and helps to keep ist shape.► It protects the body’s soft, internal organs.► It is connected to muscles that move the different bones. Bones are made of bone cels that form bone tissue. Joints are parts of the skeleton where two or more bones are connected. In some joints there are elastic tissues called ligaments that keep the bones together
MUSCLES► Muscles are made of many muscle cells.► These cells can contrac and become shorter.► They can also relax and become longer again.► Muscles contrac and relax to move different parts of the body.► Some muscles are conected to bones by long, non-elastic fibres called tendons.► When the muscles contract, they pull on the tendons and move the bones
THE HUMAN SKELETON WE CAN PUT THE BONES OF THE HUMAN SKELETON INTO THREE GROUPS:► The bones of the head.► The bones of the trunk.► The bones of the extremities. BONES CAN BE DIFFERENT SHAPES AND SIZES.► Long bones.► Short bones.► Flat bones.► Cylindrical bones.
THE CRANIUM► The bones of the head form the skull (or cranium).► These bones protect the brain and they also form the face.
SHAPES OF THE BONES► THE FEMUR IS A LONG BONE. THE CARPALS ARE SHORT BONES. THE SCAPULA IS A FLAT BONE
BONES OF THE TRUNK AND EXTREMITIES► The bones of the trunk include the spinal column, the sternum and the ribs. The spinal column is made of vertebrae. The spinal column supports the head and protecs the spinal cord. The sternum and the ribs form the rib cage. This protects the heart and the lungs. Upper extremities is connected to the trunk by two bones: the clavicle and the scapula. Each hand has got 27 bones: carpals, metacarpals and phalages . The lower extremities are connected to the trunk by the pelvis. Each foot has got 26 bones: tarsals, metatarsals and phalanges
MUSCULAR SYSTEM All the muscles of the body form the muscular system. Muscles can move and apply force. They have got different shapes. There are long muscles, flat muscles and cicular muscles. We can also classify muscles by the way they function: Some muscles are voluntary: you can control them whenever you want. Some muscles are involuntary: they work automatically. Your heart is an involuntary muscle. The muscles in your intestines are also involuntary
MUSCLES OF THE FACE The FRONTAL muscle pulls the eyebrows up. It also moves the forehead. The ORBICULAR eye muscles close the eyelids. The STERNOCLEIDOMASTOID muscles turn the head.
JOINTS► Joints are places where two or more bones are connected. We can classify joints by how much they move: FIXED joints can´t move. SEMI-MOVEABLE joints can´t move very much. MOVEABLE joints can move a lot. Inside these joints, there is a tough, flexible tissue called CARTILAGE to protect them from friction.
GOOD HABITS FOR YOUR MUSCULOSKELETAL SYSTEM Eat food with lots of calcium, phosphorus, vitamin C and vitamin D. Do different types of sport and exercise. Try to sleep on your back or on your side. Sit up straight. Bend your knees when you pick up heavy things. Wear your rucksack properly. Use both straps.