Making a baby (Reproduction and growth)

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					Reproduction   and   growth

Making a baby
You need a mother and a father to
make a baby. The mother’s body does
most of the work, but the father also
has an important job – his sperm joins
with the mother’s egg and a new                        The first cells
                                                       After 36 hours, the cell has
life begins...                                         divided and made an exact
                                                       copy of itself. These are the
                                                       first two cells of a baby.

                                                                 Eggs are the biggest cells in
                                                                 the human body. But they
                                                                 are still very small – ten
                                                                 would fit across a pinhead.

                                                            Sperm are amazing
                                                            viewed under a microscope.
                                                            They look like tiny tadpoles. You
                                                            can see their tails wriggling as
                                                            they swim.

                                                        By the time the
                                                         baby is born,
     Sperm race                                        the fertilized cell
     Millions of sperm swim towards                    will have become
     the egg cell. Only one sperm can
     join with the egg to make a new cell.             100 trillion cells.
                     What is another name for the uterus?
                                                                              Making a baby

Divide again                   The future you                         At three days
You don’t grow much in         Each cell is unique to                 The cells have carried on
the first few days. The two    you. Cells are full of                 dividing. There are now 16 cells
cells divide to make four,     instructions about what                and they are almost ready to
then eight, and so on.         you will look like.                    plant themselves in the uterus.

                    Where it all happens
The sperm fertilizes the egg in a tunnel, called a                       The cells start dividing as
                                                                         they move down the
 Fallopian tube. The fertilized egg moves down                           Fallopian tube towards
                                                                         the uterus.
    the tunnel towards the mother’s uterus.
      The journey takes about five days.                                                           Millions of sperm
                                                                                                   from the father
                                                                                                   travel up here
                                                                                                   towards the egg..

                                               This is the mother’s
                                               ovary. It releases
                                               one egg every month.

  This is the uterus. It                    Arriving in the uterus
  is about the size of a
  pear and has
                                            The ball of cells plants
  muscular walls.                           itself in the wall of the
                                            uterus. In this warm,
                                            dark place the baby
                                            will spend the next
                                            40 weeks growing
                                            and developing.
                                       The womb.                                                                 95

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Tags: Human, body