Enzymes are proteins. When the temperature rises above the optimum temperature, the protein will denature and thus loose its functional shape.
No they aren't scavengers they are parasites.
If 2n = 52, then in case of monosomy the equation becomes
2n - 1, which is equal to 51.
Monosomy is the existence of only 1 chromosome in a particular cell instead of the normal diploma pair.
The correct answer here is "cell membrane". Generally it makes sure that nothing enters or leaves the cell, except by its highly guarded "gates", such as ion channels, that let some particles through - but they're very picky about whom to let in!