The cell membrane controls what comes in and out of cells.
the cell membrane
If you mean the cell membrane, it keeps lets things in and out of the cell.
What is the word thatWhen a membrane allows some things in but keeps others out
gravity keeps things in orbit
For one thing, it's spelled PLASTIC WRAP and two. Aluminum foil keeps things cool, or cooler by how good it is as a insulator. It lets the temperature sort of flow through where it needs to go. And you can kind of control this by rolling the foil thicker or thinner.
The male keeps it safe and when there ready he lets them go.
so you bagge keeps things in and storaged, what keeps things out and available?
It keeps the eyes moist which keeps them healthy which lets us see properly which can help us survive.
Because they are bifocals. Bi=two. The lower half lets you see things Close, the upper half lets you see things farther away. Like two glasses in one.
sprinkler
Because it lets you think and it keeps you hydrated so you can think proper.
gravity keeps us in a circle