Question

I need help with it. And it includes some things that are happening in the lungs and heart.

Answer 1

Explanation:Adrenaline levels rise , which stimulates the heart to beat fast . Capillaries in the muscles open wider, increasing blood flow there by up to 20 times. The muscles of the rib cage assists the diaphragm to pull in up to 15 times oxygen than at rest. Breathing gets faster but also deeper.