Yard is to fence as cell is to membrane. Just like a fence surrounds a yard and allows certain objects in and out, a membrane surrounds the cell and only allows specific nutrients inside of it.
The fence
It would be the walls of the school or the fence around it.
A fence that keeps wolves from raging at you.
cell membrane fence nucleus townhall cytoskeleton bridges and buildings scrap yard lysosomes
The fence/wall surrounding an amusement park.
The Fence because it keeps everything safe from the surrounding environment.
the cell membrane is like a guard because it only allows chemicals in and out of the cell
I think the border of the city or like a fence or wall would be the best one I can think of.
true
True.
The plasma membrane could be considered the gate to the city. :)