Species are single organisms that are able to reproduce, while a population is a group of species living in the same general area.
Do you want the catholic answer or do you just want a general answer, because it could be an opinion.
I believe Enthalpy is the scientific term for the changes. The specific changes each item listed undergoes is hard to say correctly without knowing the options. Could you list the answers to choose from so I can get a better understanding of what they want in the answer?
