BIOCHEMISTRY The study of compounds, chemical reactions, and molecular interactions that are involved in the production, maintenance and reproduction of living organisms.

ATTRIBUTES OF LIFE Adaptation – the presence of body structures that make living things fit to live in its habitat Growth and repair – the ability to add new tissue or to replace damaged parts Reproduction – the ability to beget offsprings Metabolism – the biological or chemical activities or functions that provide energy Complexity and organization. Complexity refers to elaborate structures needed to carry out laborious functions like metabolism. Organization is putting the different body structures into order, so that the organism can function effectively and efficiently Regulation – the ability to keep the functions under control through the use of substances like hormones and enzymes Characteristic size and shape Responsiveness to stimuli or sensitivity – the ability to respond favorably or unfavorably to its environment Locomotion – the ability to move on its initiative, under its control Variation and Change – no two organisms are exactly alike (variation) and no organism remains unchanged forever. Adaptation and evolution are mechanisms of change Stereospecificity – the ability of certain molecules present in an organism to interact with nature in a left- or right-handed manner.

The Chemicals of Life  Water – all life forms contain water  Organic Compounds - nucleic acids - proteins - carbohydrates - fats and lipids  Inorganic elements - bulk elements (N, Na, Mg, P, S, Cl, K and Ca  Trace elements (Fe, Zn, I)