The concept of energy and its transformations is useful in explaining and predicting most natural phenomena. Within an organism it is responsible for growth and development of a biological cell organism. Energy is thus often said to be stored by cells in the structures of molecules of substances such as carbohydrates which release energy when reacted with oxygen.
The direction of transformations in energy is often described by entropy equal energy spread among all available degrees of freedom considerations are permitted on a but certain larger transformations are not permitted because it is statistically unlikely that energy or matter will randomly move into more concentrated forms or smaller spaces.
The human equivalent assists understanding of energy flows in physical and biological systems by expressing energy provides a for the use of a given amount of energy. In geology mountain ranges, volcanoes, and earthquakes are phenomena that can be explained in terms of energy transformations .The concept of energy is widespread in all sciences.
In biology, energy is an attribute of all biological systems from the biosphere to the smallest living organism. In human terms the human equivalent human equivalent energy for a given amount of energy expenditure, the relative quantity of energy needed for human metabolism, assuming an average human energy expenditure of are driven by various kinds of energy transformations.