Why do Organisms need a way of storing energy?
Organisms have to work in order to survive. The work that is done by the organisms uses energy which is essential for the survival of it. Every biological cell needs some energy to carry out its own activities. Likewise all the cells and in turn the whole organism are actually carrying out all the metabolic processes like respiration, excretion, locomotion, thinking, doing some action, and digestion. These processes are performed by the organism by utilizing the energy released from the food. The energy that is essential for the body of the organism to perform all its processes should be available to it.
This energy obtained from the food is used by all the systems to function properly. The energy is transformed from glucose into ATP and NADH2 in animals and ATP+NADPH2 in plants. These two types of molecules act as energy molecules which are utilized in all the metabolic processes to sustain life. These energy molecules are stored in the cell organelle called as mitochondria.
Every cell absorbs glucose from simple or complex carbohydrates. Glucose also results from the proteins and fatty acids. The resultant glucose is utilized to gain energy molecules through glycolysis, Kreb’s cycle and electron transport. Cellular respiration is the process that occurs to obtain cellular energy. Cellular respiration releases the glucose into energy molecules and stores it in the mitochondria. The raw materials used for cellular respiration are glucose, oxygen and water. The glycolysis step of cellular respiration produces 2 ATPs, Kreb’s cycle produces 1 ATP and electron transport chain produces 34 ATP molecules.
The bonds that exist between ATP molecules store lot of energy and the cells store this energy for making them to be used in metabolic reactions. If the energy is not stored as ATP molecules, the metabolic reactions cannot use glucose directly as source of energy. So, there is necessity for the organisms to store energy in their cells.