Mutualism is when two organisms are involved and they both benefit where as parasites is when two organisms are involved, but one is benefitted while the other is harmed.
-Hope I helped!
The R group varies, and it is the carbon-phosphate backbone
Both they willo still look a like
The main function of the PNS is to connect the CNS to the limbs and organs. The PNS sends information to the CNS as quickly as possible.
I hope this helps :)