Membranes are barriers and “gatekeepers”, they only let certain molecules pass through them.
they also transport nutrients to the cell
Explanation:
In chemistry, water(s) of crystallization or water(s) of hydration are water molecules that are present inside [crystal]s. Water is often incorporated in the formation of crystals from aqueous solutions. ... Water of crystallization can generally be removed by heating a sample but the crystalline properties are often lost
I got this idk if it's correct: For measuring large distances, the kilometer (103 or 1000 meters) is often used. The basic unit of volume in the metric system is the liter (l). The most common derived unit is the milliliter (ml) (10-3 or 1/1000 of a liter). The volume of a milliliter is equal to the volume of a cube 1 centimeter per side.
They are called isotopes.