When biomedical researchers design drugs that must enter cells to be effective, they sometimes add different groups to make the drug molecules more likely to pass through plasma membranes. what kind of chemical group would you choose to add to your drug? 2. responding to their environment, plants alter the permeability of their phospholipid bilayer by incorporating different percentage of different components. cold temperatures would decrease the permeability of the plant’s membrane. how should it respond?

1. Non-polar group

2. Increase cholesterol in the phospholipid bilayer

Explanation:

1. The plasma membrane of cells is made up of two layers of phospholipids, this is to insure that there is a distinct separation in the contents of the inside of the cell, from the outside. Water (a polar molecule) cannot easily pass through the membrane, hence a non-polar molecule would pass through easier.

2. Cholesterol in the plasma membrane increases fluidity, hence if the plasma membrane's permeability is decreasing due to the cold temperature, increasing fluidity and permeability would then allow the membrane to retain its function.