The concept of energy and its trnasformation is useful in explaining and predicting most natural phenomena. (a) What is the concept of energy in the context of chemistry ? (b) How do we associate energy with biology ? (c ) What is the roal of energy transformations in geology ? (d) What role does energy play in life ?

Explanation

(a) In the context of chemistry, energy in an attribute of a substance as a consequence of its atomic, molecular of aggregate structure. Since a chemica transformation is accompanied by a change in one or more of these kinds of struchture, it is invariably accompanied by an increase or decrease of energy of the substances involved.
(b) Energy is stored by the cells in the structures of molecules of substances such as carbohydrates (including sugar), lipids, and proteins which relase energy when reacted with oxygen in respiration.
(c ) In geology, continental drift, mountain ranges volcanoes, and earthquakes and phenomena that can be explained in termsof the Earth's interior.
(d) Life exists because there is energy. All living organisms rely on an external source of energy- radiation from the Sun in case of green plants, chemical energy in some form in the case of animals to grow and reproduce. The daily 1500- 2000 Calories (6.8 MJ) recommended for a human adult are taken as as a combination of oxygen and food molecules.