D) Enzymes make nonspontaneous reactions become spontaneous
Explanation:
Being spontaneous or non-spontaneous in nature depends on the difference in energy levels between substrates and products of the reactions. A reaction with substrates at higher energy levels than the products are spontaneous ones. On the other hand, the reactions wherein products have higher energy content than the substrates are non-spontaneous.
Enzymes do not change the energy levels of substrates and products, so, they can not make a non-spontaneous reaction to become a spontaneous one. Enzymes only lower down the activation energy for a reaction and thereby make the non-spontaneous reaction to occur at a faster rate.
If a person is shot, and the bullet destroys the part of the brain called the medulla, which maintains basic life functions (heart rate, breathing), there is virtually no chance for surviving that injury
Necessary because it keeps heat in and keeps the planet at the right temperature for life. It can harm the planet if more pollution occurs and the greenhouse gas effect traps too much heat and causes global warming
