Why Do We Sleep at Night and Stay Up During the Day?

Your body has a little clock inside it. It tells you when to be awake and when to sleep, like a tiny timer in your head! This clock is affected by light, when the sun goes down, your body starts feeling sleepy, and when it comes up, you feel more alert.

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Examples

A child goes to bed when it gets dark, just like their parents.
An office worker feels tired at night and wakes up when the sun comes out.
A cat sleeps during the day and is active at night.

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Categories: Biology · circadian rhythms,sleep patterns,biological clocks