I think its a hope that helped :)
Carbon is the only element that can form so many different compounds because each carbon atom can form four chemical bonds to other atoms, and because the carbon atom is just the right, small size to fit in comfortably as parts of very large molecules. ... They can even join "head-to-tail" to make rings of carbon atoms.
3 is b PROKARYOTIC AND EUCARIOTIC
ANSWER:
Needed to form cell membranes
I hope I was of help to you :)
What organ integrates the brain nervous organs with the endocrine system? Hypothalamus
