Science, asked by psneShahRakesha, 1 year ago

why we yawn when we are sleepy or drowsy.

Answers

Answered by Lipimishra2
285
When we are tired,feel sleepy,drowsy,bored, we breathe slowly and don't take much oxygen to make energy.So we open our mouth wide open and take more oxygen to fulfil our requirement of breathing.
Answered by HARSHGARG
132
When you feel sleepy..it is actually the brain cells which are in a sense of saying..going to fall asleep for lack of oxygen (hypoxia or hypoxemia). Also when we feel drowsy, our respiratory rate being controlled by reflex centres in our brain falls. This is a vicious cycle. The yawn breaks this cycle.
Similar questions