Nitrogen-fixing bacteria change nitrogen into a form of soluble nitrates that plants can use ...the air is 80% nitrogen but it is in N2 form which plants cannot use
The circulatory system - hemoglobin in the blood transports oxygen :)
OK so I'll give you two examples you can catch it if someone who is infected coughs or sneezes so basically it can be spread via airborne or you can even get it from sharing food or drinks also the best way to get rid of strep will be antibiotics/over the counter medicines or gargling warm salt water
Protons are equal to atomic number. Meaning the answer would be 64.