Page 37 - Active Science 5 Ebook and Activity
P. 37

Let’s Recapitulate

            Fill in the blanks by choosing the correct option from the given words.
                gliding       moveable      ball and socket       backbone      fixed


            1.  __________________ joints are the most movable joints of the body.
            2.  Bones of the skull are ___________.
            3.  ____________ joint is found in the bones of wrist and ankle.

            4.  The skull is connected to the ______________ with a pivot joint.
            5.  ________________ joints are of four types.



        Cartilage

        In various parts of the body like elbow, ankle, knee and also between the vertebrae in the
        backbone, a tough, elastic tissue is found. This is known as cartilage. Bones, cartilage
        and muscles help us in movement. Cartilage prevents the bones from rubbing against

        each other and wearing out.

        Cartilage is also present in the top part of the ear or the tip of the nose. Therefore, these
        parts are soft to touch.

        Cartilage
                                                                         Factual Study
                                                                         Our hands have 54 bones with each
                                                                         hand with 27 bones, and each foot
                                                                         with 26 bones. Therefore, our two
                                                                         hands and two feet together have 106
                                                           Nasal         bones which is more than half of the
                                                          Cartilage
                                                                         bones in our entire body.




        Activity 3.2

        Make the models of the different movable joints in the human body.



        M uscles

        The  movement  of  the  bones  is  made  possible  due  to  muscles.  A  muscle  is  a  fibrous
        structure made up of proteins. We have over 600 muscles in the body. They are under

        the skin and surrounded by bones. Tendons attach muscles to the bones. You now know
        that the joints allow  our body to move in different ways, but for movement to happen,
        the bones must be connected to muscles. When two muscles come into play, there is a
        movement in the bone. When you move your arm or leg, one muscle has to contract and
        another muscle has to relax. There are two types of muscles.


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