Page 78 - Science Course 2 (Book 1)

Mo3-L2a: What is Puberty?

Menstruation (periods) happen due to the hormones Key Concept
changing in your body.
What is Puberty?

How is puberty related to the ability to reproduce?

Even before birth, a girl has 1-2 million tiny eggs
(Ovum) in her ovaries. When puberty is reached
usually an egg is released each month from her
ovaries.
SUMMARY
Egg released What is Puberty?

Progesterone Puberty is when a child begins to change into
Estrogen an adult.

Lining of Lining Lining
Menstruation the uterus maintained breaks down
builds up (menstruation)

Day 1 Day 7 Day 14 Day 21 Day 28
uterus lining Puberty starts when extra amounts of
chemicals called hormones start to be
The egg moves from the ovary and along the produced in the body.
fallopian tube and down into the (womb) uterus.

If the egg is fertilized by sperm then a pregnancy
will occur. If the egg is not fertilized then the lining of
the womb and the egg leave the body through the
vagina; this is called menstruation.
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