Why do we need the endocrine system?

Explanation:

The endocrine hormones help control mood, growth and development, the way our organs work, metabolism , and reproduction. The endocrine system regulates how much of each hormone is released. This can depend on levels of hormones already in the blood, or on levels of other substances in the blood, like calcium.

Without your endocrine glands — and the hormones they release — your cells wouldn't know when to do important things. For instance, your bones wouldn't get the message that it's time for you to grow and get bigger.

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