Changes in humans during their lifetime

Part ofScienceAnimals including humansYear 5

Human life cycles

An illustration of women and children at the park
Image caption,
All humans go through the same life cycle

As we grow from being babies to elderly adults, our bodies go through lots of changes.

These human life cycle changes happen gradually over time.

All humans go through the same life cycle.

Humans are small at the start of their life. Over time they grow bigger and their bodies change.

When they are grown up, they might have children of their own.

An illustration of women and children at the park
Image caption,
All humans go through the same life cycle
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Watch: How humans change during their lifetime.

Learn about the life cycle of humans.

Fascinating facts

An illustration of a pregnant woman and a foetus
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The human life cycle starts when a woman becomes pregnant and a baby develops in her womb
  • When you grow older, you might become a bit shorter. With age, bones tend to shrink in size and density, weakening them and making them more susceptible to fracture.

  • As people age, their skin wrinkles, their hair can often thin and it may even turn grey.

  • Unlike sharks which have multiple sets of teeth throughout their lifetime, humans only have two sets of teeth, our baby (or milk) teeth and adult teeth.

  • Babies in the womb can hear everything around them, from around 20 weeks. A developing baby can identify different noises and the tones of people's voices.

  • Our brain stops growing as we reach adolescence but keeps developing and maturing until adulthood.

  • Babies are born with all of the brain cells they will have throughout their life.

An illustration of a pregnant woman and a foetus
Image caption,
The human life cycle starts when a woman becomes pregnant and a baby develops in her womb
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Slideshow: Human changes throughout a lifetime

Image gallerySkip image gallerySlide1 of 6, An ultrasound of a foetus., Foetus At the foetal stage, a baby is growing inside its mother's womb.

The six stages of a human life cycle

The six stages of the human life cycle
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The six stages of the human life cycle
A human skeleton
Image caption,
A human skeleton

Did you know?

A baby is born with around 300 bones. Some of these eventually join together leaving adults with 206 bones that make up their skeleton.

Animals which have a backbone, including humans, are called vertebrates. The human spinal column is made up of 33 bones called vertebrae.

A human skeleton
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A human skeleton
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Important words

A baby crawling
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A baby crawling

Adolescence – The period of transition between childhood and adulthood.

Adulthood – The period where humans reach maturity and the stage where some women may have babies.

Baby – A baby is born after spending around nine months inside its mother’s womb.

Childhood – In childhood children learn to walk and talk.

Foetus – An unborn human that develops and grows inside the uterus (womb) of its mother.

Life cycle – A life cycle is the different stages of life for a living thing.

Old age – The last stage in the life cycle of a human.

Womb – An organ in a woman where offspring are conceived, and where babies develop and grow before being born.

A baby crawling
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A baby crawling
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Activities

Activity 1 – Stages in a human life cycle

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Activity 2 – Take the quiz

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