Question

I want to know why we yawn when we are sleepy or drowsy?​

Answer 1

Explanation:

When we are sleepy or feel drowsy, we yawn because our brain cells lack sufficient amount of oxygen. The deep breath associated with yawning helps us to drawn in more oxygen and supply the much needed oxygen to the tired body organs including the brain..

Answer 2

Answer:

Explanation:

When we are sleepy or feel drowsy, we yawn because our brain cells lack sufficient amount of oxygen. The deep breath associated with yawning helps us to drawn in more oxygen and supply the much needed oxygen to the tired body organs including the brain..