Why should body temperature not be allowed to fluctuate too much? ​

Because that can destroy the helpful enzymes in the body, and therefore cause a lot of problems or maybe cause death

passive transport is a movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy input. unlike active transport, it does not require an input of cellular energy because it is instead driven by the tendency of the system to grow in entropy.

so, according to what that says, i believe it's hypertonic and hypotonic.

good luck!