The one that makes the most since is b. Hope this helps some !
They help defend you main cells i think i learned this
False, i think. I believe men and women are the same in terms of exercising
What I do before a big exam is study, get goods amount of sleep, stretch your body, practice any breathing Technics, etc. You shouldn't be stressed out from a test, just study and do things to release the stress and ace that test!
If the respiratory system is not working, then breathing would be very difficult. That would lead to problems with the cardiovasculary system (Another name for the circulatory system) because pumping oxygen and blood places would be very difficult. Can't get oxygen around your body if your having a lot of trouble breathing.
~Silver