Answer:
If the active site is altered, the enzyme can no longer perform its catalytic activity
Explanation:
Changes in temperature or pH alters the structure of the enzyme. Enzymes have catalytic activity that lowers the activation energy required for a reaction to proceed.
Enzyme catalytic activity is facilitated by the active site - a specific region of the enzyme where the reactants bind.
At the active site, the conditions are optimal for the reaction to take place (the active site gets the reactants in the perfect position to make contact and react).
If the structure of the active site is compromised, it won't have catalytic activity anymore and won't be able to catalyze the reaction
B) No, many microorganisms, like those in your gut, are beneficial
As is turns out there are only about 100 different bacteria which are pathogenic. All other bacteria are completely harmless and, as this question states, some are crucial for proper human health as we exist in a symbiotic relationship with them. Bacteria in the large colon provide nutrients to us, and play an important role in the development of the immune system.
There in different orders.
The ultimate energy source would be he sun.