Page 36 - Active Science 5 Ebook and Activity
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Joints
          A joint is the place in the body where two bones meet. Strong bands of tissue called

          ligaments hold two bones together at a joint.

          There are two types of joints in our body – immovable and movable. Since bones of the
          skull are fixed, the joints between them are immovable. Joints in other parts of the body
          are movable and are of four types.

           1.  Hinge Joint:  The  hinge  joints  are

               similar to the movement of the hinges                                                        Knee
                                                                                                            Joint
               of a door. They can move back and forth.
               Bones in fingers, knees, toes and elbows                         Elbow
               are  all  hinge  joints.  For  example,  we                       Joint

               can fold our elbows to touch our neck
               and  shoulders.  It  enables  movement               Finger                                    Toe
               similar to the opening and closing of a               Joint          Hinge Joints             Joint
               hinged door.




           2.  Ball and Socket Joint: These joints
               are the most flexible joints of the body.                                                        Hip

               You  can  move  these  joints  around                                                           Joint
               very comfortably. These joints help in
               movement  such  as  rotating,  bending                   Shoulder
               and  stretching.  The  shoulder  joint                     Joint

               and hip joint are examples of ball and                          Ball and Socket Joint
               socket joints.




           3.  Pivot Joint:  The  skull  is  connected                                        Joints between
               to the backbone with a pivot joint. It                                          the skull and
               allows us to move our head downwards,                                             backbone

               upwards and sideways by nodding and
               shaking of the head.                                             Pivot Joint



           4.  Gliding Joint: The type of joint which                              Ankle

               allows the bones to slide over each other                           Joint
               is called gliding joint. This type of joint
               is found in bones of wrist and ankle.                                                         Wrist
                                                                                                              Joint
                                                                                    Gliding Joint

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