A joint is a place where two or more bones meet or articulated.
Types of Joint
These are joints or regions where two or more bones are firmly attaches to one another or firmly fixed by ligament in such a way that movement of these bones are not possible. Example of some places in the body where
Immovable joints are present are skull and pelvic girdle.
The immovable joint of the skull are called suture
They are joint or region of the body where movement of joint is possible. Most of the bones are held together by movable joint
Types of movable joint
- Ball and socket joint
These are joints that allow movement in all directions <3600>the joint are found in the shoulder and hip joint
. 2. Hinge joints
It is found at the elbows and knee it allow movement in only one direction
3. Gliding and sliding joint
It allows gliding of the bones over one another. Example of this joint are found in the wrist and ankle
4. Pivot joint
Pivot joint are found in the neck between the atlas and axis. It permits nodding and rotation of one part of the body on another Structure of joint.
The main part of the joint consist of the followings
These are though partly elastic bands of tissue which hold two bones together at a joint
Tendons are extension of connecting tissue which join muscle to the bones
Articular cartilage these are found at the surface of the bones at joint plays the role of cushioning by protecting them from wear and tear during movement
Synovial Membrane is responsible for the secretion of synovial fluid
Synovial fluid is the fluid which lubricate the joint and thus reduce shock as well as friction between bone.
Capsule is the space which contain the synovial fluid
The skeleton can be move due to the muscular contraction. Muscle are joined to the bone by means of tendons . Tendon transmit the pull from a muscle into the bone, antagonist pair of muscle work against each other moving the same limb into opposite direction, thus the biceps bend the arm while the triceps straightened. The contraction of the flexor muscle attains elongation of the biceps. The flexor muscle antagonistic pair i.e triceps the limbs while the extensor muscle e.g triceps straighten the arm.
FUNCTIONS OF SKELETON (Review)
1.It gives support ,shape, and rigidity
2.It protects the delicate organs of the body such as the brain, spinal cord and heart
3.It helps in movement
4.The bone marrows manufacture the red blood cells
5.It provides space for the attachment of the muscles
6.The ribs and sternum help the respiration
7.The skeleton stores some mineral salt e.g calcium and phosphorus