Question

lets apply the concepts you just learned about selective permeability. predict which of the following substances will cross a lipid bilayer that lacks transport proteins more readily than others. then, move the options in order from most likely to cross at the top to least likely to cross at the bottom. potassium ions (k⁺) nitrogen molecule (an n atom triple - bonded to an n atom, written n₂) water (h₂o) glycerol ch₂—oh ch—oh ch₂—oh

Explanation:

Small, non - polar molecules cross lipid bilayers most readily without transport proteins. Nitrogen ($N_2$) is a small, non - polar molecule. Water is small but polar. Glycerol is larger and more polar than water. Potassium ions ($K^+$) are charged and the least likely to cross as the lipid bilayer is non - polar and repels charged species.

Answer:

1. Nitrogen molecule ($N_2$)
2. Water ($H_2O$)
3. Glycerol
4. Potassium ions ($K^+$)