Page 148 - DK Children's Encyclopedia

Life cycle SEE ALSO

▸ ▸ Body cells p.41
▸ ▸ Cells p.56
Like all animals, humans are born, grow up, and can have ▸ ▸ Genes p.119
children of their own. This is called a life cycle. There are ▸ ▸ Human body
many different stages that a human goes through on their p.130

journey from birth to adulthood. ▸ ▸ Metamorphosis
p.166

▸ ▸ Skeleton p.228

Baby Toddler
Babies are very small and Toddlers learn how to walk,
can’t feed themselves or talk. talk, and feed themselves.
They need parents or carers They grow teeth called milk
to take care of them. teeth, which fall out and are
replaced with adult teeth.

Growing up
Everyone starts life as just
two cells. We grow into
children and eventually adults. Child
Children grow
and learn quickly.
Sperm and egg They are smaller
than adults and
A sperm cell joins still have a lot of
an egg cell inside skills to learn.
the mother’s womb.
After nine months,
the cells have grown
into a baby.

Unborn baby

Babies grow inside the
mother’s womb. Doctors look
at the growing baby using a
The process called an ultrasound.
oldest person At 12 weeks a baby is about
the size of a lime.
recorded died at 122
years and 164
days old.

Adult Teenager
Adults can make their own Chemical signals called
children. Males produce hormones tell the body to
sperm cells and females start changing from a child
produce egg cells. into an adult.
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