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What is the skeleton? What does it do?
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The skeleton is the entire collection of bones, cartilages, joints, tendons and ligaments inside our body.
Bone is a type of tissue that contains collagen and calcium phosphate, a mineral crystal. Bones provide support and protection for body organs.
Cartilage is a form of tissue that contains chondrin. Cartilage provides flexible support for certain structures in adult humans including the nose, trachea, and ears.
Tendon is a fibrous band of connective tissue that is bonded to bone and connects bone to bone.
Ligament is a fibrous band of connective tissue that joins bones and other connective tissues together at joints.
Joint is a site where two or more bones or other skeletal components are joined together.
The skeletal system is one of the major systems of the human body, and has four major functions:
• It protects vital organs, such as the brain, heart, and lungs.
• It supports the body and gives us our distinctive shape. Without our skeleton, we would look more like a slug.
• It allows us to move in particular ways.
• It makes new blood cells to maintain a healthy bloodstream.
With so many important jobs to do, the skeleton is a vital part of the human body.
The skeletal system in an adult body is made up of 206 individual bones. The bones form the skeleton of the body. The bones which form the skeleton or bony framework of the body include the bones of the head and the face, the bones of the trunk, the bones of the lower and upper limbs.
The bones of the head and the face:
At the upper end of the backbone there is the skull (cranium). Inside the skull is the brain. The bones of the head include the bones which make up the box-like structure, the skull, and freely movable bone which forms our lower jaw. Our face is made up of 14 bones. The most important boned of the face are mandible (lower jawbone) and maxilla (the upper jawbone).
The bones of the trunk:
The most important part of the skeleton is the backbone (spinal cord,vertebral column). It is so important that naturalists divided all animals into two classes - those which have a backbone and those which have none. All the higher animals have a backbone, or vertebral column and they are therefore called (называются) vertebrate animals. The others are called invertebrate animals. The vertebral column, or the spinal column, is made up of 24 small bones, each of which is known as a vertebra.
There is another box of bones in front of the backbone. The ribs, which join the backbone behind and bend round towards the breastbone in front, form a strong cage — the chest.
The shoulder is made of two bones that together allow the attachment of the arm to the body. The bones of the shoulder are Scapula and Clavicle. The scapula is a flat, triangular bone that connects the humerus (upper arm) with the clavicle. The clavicle is a pair of small long bones that join the scapula to the sternum. The clavicle is the only long bone that lies horizontally.
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The bones of the lower and upper limbs:
The bones of the hands can be divided into those that make up the upper arm, the lower arm, the wrist, the palm and the fingers.
Between the shouldet and the elbow there is only one bone (humerus).
The Humerus is a single long bone of the upper arm. It runs from the shoulder to the elbow. The humerus connects the scapula to the bones of the forearm.
Between the elbow and the wrist there are two bones (radius and ulna).
The Radius is one of the long bones of the forearm. It starts from the elbow and continues to the wrist.
The Ulna is a long bone that runs parallel to the radius, along the forearm.
In the wrist there are eight small bones. They are bound (связаны) together, but their large number allows the wrist to bend freely. The Carpal Bones are the bones of the wrist.
In the bones of the hand there are five long bones — one for each finger and one for the thumb. Each of the fingers has three bones, and the thumb has two. Thus we have twenty-seven bones in the framework of the hand and wrist alone. The Metacarpal Bones are the bones of the palm. Phalanges are the bones of the fingers.
The bones of the legs are those that make up the thigh, the lower half of the legs, and the feet.
The Pelvis is a bone attaches to the spinal cord that joints the femur and the trunk.
Between the pelvis and the knee cap (patella) there is only one bone (femur).
The Femur is the longest bone in the human body, and is also known as the thigh bone.
Between the patella and the ankle there are two bones (tibia and fibula).
The tibia is the second longest bone in the human body. Along with the fibula, it forms the lower part of the leg below the knee. The tibia is considered to be the strongest bone of the body. It is commonly known as the shin bone.
The fibula is a long but thin bone which, along with the tibia, forms the lower part of the human leg. It is attached to the tibia at both the ends. The fibula is also known as the calf bone.
The patella is a triangular bone that forms a protective cap over the knee joint. Also known as the kneecap. It is the largest sesamoid bone in the human body.
The tarsal bones are the bones of the ankle, and there are 14 tarsal bones, 7 on each foot.
There are 5 metatarsal bones in each foot, one corresponding to each digit. These lie between the tarsal bones and the phalanges.
The Phalanges are bones of the toes of the feet. There are 5 phalanges in each foot.
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