THE MUSCULOSKELETAL SYSTEM The musculoskeletal system is composed of many muscles and bones. Its lets you move different parts of your body and get you around from one place to another. Garfield can runs with his musculoskeletal system
THE FUNCTIONS OF THE SKELETON Humans have got an internal skeleton. It is made of 206 different bones. The skeleton perfoms three main functions: · Its supports the body and helps to keep its shape. · Its protects the body’s soft, internal organs. · It is connected to muscles that move the different bones. Bones are made of bone cells that form bone tissue. These cells can grow and reproduce to repair broken bones.
THE SKELETON: Supports the body Protects the body’s softYour feets carry all the weight of your The ribs protects organs like the heart or body. the lungs
MUSCLES Muscles can contract and relax to move different parts of the body. Some muscles are connected 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 Bones can be different shapes and sizes. There’re long bones, short bones, flat bones and cilyndrical bones ← The femur is a long, cilyndrical bone The parietal is a flat bone → ← The vertebrae is a short bone
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
THE BONES OF THE HEAD The bones of the head form the skull (or cranium). These bones protect the brain and they also form the face.
THE BONES OF THE TRUNK The bones of the trunk include the spinal column, the sternum and the ribs. · The spinal column is made of smaller bones called vertebrae. The spinal column supports the head and it also protects the spinal cord. · The sternum and the ribs form the rib cage. This is protects the heart and the lungs.
THE BONES OF THE EXTREMITIES Each upper extremity is connected to the trunk by: the clavicle at the front, and the scapula at the back. The bones of the upper extremities form the arms, hands and fingers. Each hand has got 27 bones called carpals, metacarpals and phalanges.
THE BONES OF THE EXTREMITIES The lower extremities are connected to the trunk by the pelvis. The bones of the lower extremities form the legs, feets and toes. Each foot has got 26 bones, called tarsals, metatarsals and phalanges.
MUSCLES Muscles can move and apply force. They have got different shapes ans sizes: circular muscles → ← long muscles flat muscles →
MUSCLES We can also clasiffy muscles by the way they function: · Some muscles are voluntary: you can’t control them whenever you want. · Some muscles are involuntary: you can’t control them because they work automatically: Your heart and your intestinal muscles are involuntary.
JOINTS Joints are places when to or more bones are connected. We can clasiffy joints by how much they move: · Fixed joints can’y move. · Semi-moveable joints can’t move very much. · Moveable joints can move a lot. Inside this joints, there is a tough, flexible tissue called cartilage.
JOINTS AND PAIRS OF MUSCLES Muscles often works togheter in pairs.They take turns contracting and relaxing. When one of the muscles contracts, it becomes shorter and pulls on the other muscles. At the same time, the other muscle relaxes and becomes longer.