Our cells get their energy from Choose...chemicalbiologicalelectricalnone of the above energy held in molecular bonds of carbohydrates, fats and proteins. Green plants use light energy from the sun to make carbohydrate in a process called Choose...oxidationcarboxylationphotosynthesischlorphyllization. Our bodies extract energy from food in three stages. Stage 1 consists of digestion, absorption, and Choose...break downsynthesismetabolismtransportation. Stage 2 includes the breakdown of many small molecules into a few key metabolites. In Stage 3, the complete breakdown of metabolites to water and Choose...carbon dioxidehydrogenoxygencarbon liberates large amounts of energy.

The term Choose...catabolysismetabolic pathwaymetaboliteroute of metabolism describes a series of chemical reactions that either break down a large compound (catabolism) or build more complex molecules (anabolism). Cells are known as the 'work centers' of metabolism. The basic animal cell is divided into two parts – the Choose...nucleusmitochrondriagolgi apparatuscell membrane and the Choose...ribosomeendoplasmic reticulumcytoplasmlysosome, which is filled with a fluid called cystosol. The Choose...mitochondrionribosomeslysosomesnuclei are power generators that contain many important energy-producing pathways. Choose...NeurotransmittersEnzymesHormonesGenes and their cofactors speed up chemical reactions in metabolic pathways.