biochemical reactions

Each time you chop onions, you have to find ways to cut them together so that you don't make eye contact with the onions so you don't have to 'shed tears'. Why is this happening?

Have you ever wondered why our body releases carbon dioxide (CO2) when breathing, not another gas?

Certainly everyone used to have a childhood attached to a bug named fireflies, a light flickering every night that any child is interested and curious.