Page 7 - Active Science 5 Ebook and Activity
P. 7

Why do geckos lick their eyes?
          Gecko belongs to the lizard family. Most lizards
          have eyelids to wipe their eyes but the gecko
          does not have any. The eye in the gecko is
          covered with a scale. Thus, in order to keep its
          eyes moist and clean, the gecko licks them using
          its long tongue.



          Why do lizards lose their tails?
          You must have noticed when you chase a lizard for quite long. It leaves behind its dancing tail
          that keeps you busy for a while. This is an adaptation in the lizard that puzzles its enemy and gives
          it time to escape.  A new tail grows in a few weeks.



                                                    Why don’t non-stick frying pans stick?
                                                  Non-stick frying pans are a necessity in every kitchen now a
                                              days. The inside of these pans is coated with teflon, a kind of
                                           plastic invented in the late 1930s. The teflon coating has fluorine a
                                          chemical molecule which repel almost all other materials to
                                         stick. This is the reason this coating provides a non-
                                       sticky quality to the pan.






          Why do leaves change colour in autumn?
          Inside the leaf are millions of little packets of colour
          pigments. The green ones are called chlorophyll, the
          yellow ones are called xanthophyll and the orange
          ones are called carotene. All through the winters,
          chlorophyll is busy catching sunlight and preparing
          food for the plant. Thus, it covers all the other colours. It
          uses water that is transported up the water tubes from
          the roots. But when winter comes, a thin layer of cells
          grows over the water tubes and no water can enter the
          leaf. Without water, the chlorophyll starts disappearing
          and the other colours can finally be seen. So it is not the
          leaf that changes colour but the green colour in leaves
          diminishes.
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