Nutritional Bioenergetics in Fishes

The maintenance of all living things requires energy. Animals are unable to absorb or emit solar energy. The complex chemicals that the animal eats oxidize to provide them with the energy they need. The feed has energy that isn't available until the digestive process reduces its complex molecules to simpler ones. Following absorption into the animal's body, the digested materials undergo oxidation reactions that release energy. Fish species differ significantly in their capacities for digesting their diet since they vary greatly, spanning from herbivores to carnivores. The word ‘Thermodynamics’ comes from the greek words, ‘thermo’ means heat & ‘dynamics’ means power. It is the ability to do work and the conversion of heat to other forms of energy. An open system allows both heat and matter to enter or leave the system and continuously interact with the environment. The interaction can take the form of information, energy, etc. In these regards, fish acts as an open thermodynamic system, which continuously interacts with its environment for energy, which is used for its growth, feeding, reproduction, etc.