It's basically a wave that moves back and forth at regular speed through matter. because of that it transfers energy through a medium (matter). however the movement of the wave is limited because of this but it can still move over long distances. so because of this these types of waves don't move far from their original point or Equilibrium position. in short think of throwing a pebble into water and seeing the little ripples from it, that's a mechanical wave. 
        
             
        
        
        
The answer is cell wall.
The best characteristic that distinguishes the kingdom Archaebacteria from the kingdom Eubacteria is the cell wall. Archaebacteria have cell walls made of  uncommon lipids while Eubacteria have cell walls made of peptidoglycan. Speaking of structure and body type, both kingdoms include prokaryotic and unicellular organisms without differences in nutrition source, they could be autotroph or heterotrophs. 
 
        
             
        
        
        
Answer:
Neither
Explanation:
It is important to note:
Enzymes can only be denatured but not killed as enzyme is not a living thing that can be said to be alive
temperature and pH may change the 3D shape of an enzyme, this destroy the active site of the enzyme thereby reducing its activity.