S<span>mall
charged molecules such as ions can</span> pass <span>through cell</span> membranes
by facilitated diffusion using specific transmembrane protein channels, which act as
transporters that are implanted into the plasma membrane. Such transport proteins regulate the selective
permeability of cell membranes and play a critical function in cell membrane.
<span>Moreover,
this specific transmembrane protein have multiple membrane-spanning regions
that create a passage through the phospholipid bilayer, allowing charged
molecules to pass the membrane through a protein pore without interacting with
the fatty acid chains of the membrane. </span>
The water is warmed up by the sun and then it evaporates into the atmosphere. The sunlight warms the water by its heat.
Water is then cooled down and condensation takes place.
The water then finally returns back to the earth by the process of precipitation in the form of rain or ice.
Water and nutrients that are not recycled on earth are stored in the form of reservoirs.