Question

the text defines homeostasis as a \dynamic equilibrium.\ if a cell membrane were suddenly made completely impermeable (nothing could pass through it), how would this affect the cells ability to maintain homeostasis, and why?
homeostasis would fail because the constant adjustments required to maintain \dynamic equilibrium\ would become impossible.
homeostasis would improve because the cells internal environment would become perfectly stable and unchanging.
homeostasis would be unaffected since active transport is an energy - requiring process that happens only within the cell.
homeostasis would be maintained only by passive transport, as this does not require interaction with the external environment.

Explanation:

Homeostasis is a dynamic equilibrium that requires the cell membrane to allow the passage of substances in and out for constant adjustments. A completely impermeable membrane would prevent these necessary exchanges, thus homeostasis would fail.

Answer:

Homeostasis would fail because the constant adjustments required to maintain "dynamic equilibrium" would become impossible.