Page 3 - 8.4 JOINTS
P. 3

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                    • •The places where two or more bones meet are called
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                    joints. The bones are held together by a special tissue
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                    c  a l l e d   t h e    l i g a me    n t .
                    called the ligament.
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                    • •For example: our arm bends at the elbow, our legs can
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                    bend at the knee and our head can rotate around our
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                    neck. These junctions are known as joints.
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                    • •When bones move at the joints, they rub against each
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                    other. If the bones kept rubbing against each other over a
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                        n
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                    long period, they would wear out. Therefore, to prevent
                                                                                                                                 e
                    l l l o n g   p e r i o d ,   t h e y   w o u  l d   w  e  a r   o u  t .   T h e r e  f o r e  ,   t o   p r e v e n  t
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                    t t t h e   b o n e s   f r o m   w   e  a r i n g    o u t ,   t h e r e   i s   a   p r e s e  n  c e    o f   s o f t ,
                                       s
                    the bones from wearing out, there is a presence of soft,
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                    f f f
                    flexible and elastic tissues called cartilage which covers
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                    the ends of the bones where they meet to form a joint.
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                    t t t h e   e n d s   o f   t h e   b o n e  s   w   h e  r e   t h e  y   me    e  t   t o   f o r m   a    j o i n t .

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                    • •The tip of our nose and the outermost part of our ear are

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                                  p
                                                                                                                             u
                                                                                                               r
                                                                                                             a
                                                    n
                                                                                                          p
                                                                                                          p

                                                                                                             a
                                                                                                             a
                                 i
                                         f

                                                                                                                    o
                                                                                                                          o
                                      o
                                                                                                                       f


                                                                                                                 t
                                                                                                                 t
                                                                                                                 t

                                            o


                               t
                                                                                                       t
                                                                                                       t
                                                                                                       t



                                                       o
                                                                                                    s
                                                                                                    s
                                                            e
                                                                                                    s

                                                          s
                                                                                                                                   e
                                                                                                          p

                                                                                                                               r
                                                                                    a
                                                                                    a
                                                                                    a
                                                                        c
                                                                        c
                    soft due to presence of cartilage.
                    s
                                                         n

                         f
                                                            c
                                         o
                                                                                   l
                                                                                   l

                                                              e
                                                                        c

                                                                                   l
                                                                                 i
                                                                                 i
                                                                                 i
                                       t

                                                                  o
                                             p

                           t
                                                                              r
                                                                                       g
                      o
                                                                     f
                                               r
                                                                           a
                                                                           a
                                                                           a
                                                      e
                                                                                            .
                                                 e
                                                                                       g
                                                                               t
                                                                               t
                                                                               t
                                                                                         e
                                                                                         e
                                                                                         e
                                   e
                                                                              r
                                                                              r
                                                                                       g
                                u
                                                    s
                              d
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