The correct answer is :
Some substances but not other can cross the (blank ) membrane of a cell. The blank is to be filled with either cell or plasma. Cell membrane or plasma membrane is the living boundary of a cell which is made of phospholipid. It is a semi-permeable or differentially permeable membrane. It only allows small and non-polar molecules to pass through it. It prevents polar ions or molecules to pass through it
Commensalism :)
in case when bacteria and human, both are benifited.
A beacause not everything happens to all cells
I think it's surface area would be less than it's volume so it means it won't be able to get nutrition as needed.
hope this helps :P
