List 3 examples of a selectively permeable material or item. explain where it is found or used and why a selectively permeable item is needed

I have this question for homework as well.
Colander - drains water but isn't permeable enough to lager food (used to strain liquid from food)
Vacuum filter - traps dust but allows air through (used to clean)
Coffee filter - allows air through (used to make coffee)

A- phosphate group

B- 5-carbon sugar

C- nitrogenous base (adenine is a purine, just in case)

D- nitrogenous base (uracil is only found in RNA)

E- 5-Carbon sugar

F- phosphate group

Explanation: