What does the cell membrane do? how do materials cross it?

The cell membrane is a fluid structure. Its molecules are not fixed in place and can move past one another horizontally making it selectively permeable, or, semipermeable, allowing some, but not all, materials to pass through it.

a axis of a graph is a color or shade so we can all go outside and have a party so we can eat   some grilled cheese sammiches and broccoli and have some ugly fun times

i don't know why i put this, i know its not the i was just bored : p

delete this answer while you can