Astudent notices that animal cells behave differently when exposed to solutions that are hypotonic compared to certain fungi, plant, and bacterial cell. the animal cell lyses while the other three do not. what structural difference accounts for the unique way animal cells react when exposed to water.

Rigid cell walls that prevent the expansion of the cells

Explanation:

The structural difference that accounts for the unique way animal cells react when exposed to water is the absence of cell wall in animal cells.

Explanation:

Plant, certain fungi and bacterial cells have an outer covering of cell walls that protects their cell in different and adverse environmental conditions.

The cell wall of the plant is made up of cellulose, the cell wall of fungus is mainly composed of chitin and bacterial cell wall is made up of peptidoglycan.  

This cell wall prevent bursting of cell in hypotonic environment because they are rigid structures. Animal cell does not have a cell wall outside their cell membrane therefore in hypotonic condition animal cells burst due to the diffusion of excess water inside the cell.

Therefore absence of cell in an animal cell is the structural difference accounts for the unique way animal cells react when exposed to water.

the answer to your question is:

c. complementary base-pairing