How do biological clocks affect organisms?

biological clock is nothing but the rhythm which an organism follows.

it is very important for an organism to maintain biological clock, because of various reasons. some of them being

(following human examples are based on the natural rhythm where we work in the day and during night we sleep)

1. changes in the hormones of the organism (cortisol levels in the humans during sleep decreases and then it rises during the morning time when you are about to wake up)
2. reduction or increase in the activity of different organs or parts of tissue (brain activity in the sleep time increases)
3. relaxation of the muscles during night

there are ill effects once the rhythm is broken

1. stress in the human
2. feeling weakness
3. disruption in the hormone balances

I hope you get the idea of how the biological clock is affecting an organism example here was human

other organism like plants, animals also exhibit a similar kind of rhythm which is maintained and changed during a particular season too.

anybody is welcome to improve the answer
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