List three criteria cells used to select materials to enter or leave the cell

Question

Then, explain the role of each criterion in determining the type of transport a cell will use for different sized molecules. For instance, small molecules move across the membrane by diffusion, given they are moving with the concentration gradient; larger molecules move by facilitated diffusion if they are not charged and not lipid soluble, and very large molecules move by endo/exocytosis

Answer 1

In diffusion:

Materials that can only undergo in diffusion are nonpolar and slightly nonpolar and small molecules. This is because of the hydrophilic head and hydrophobic head of the cell membrane. Examples of these materials are CO2 and O2.

In facilitated diffusion:

Almost any molecules and ions can pass through here, they just need to find the matching protein canal, so that they can pass through. And transport will stop until there is balance of solutes between inside and outside of the environment. Examples of materials are glucose and K+ ions.

In active transport:

All of the needed and "rare" molecules can undergo here, to attain the plant's required nutrient intake. As long as ATP will be used, then it will be possible.