Biochemistry can be defined as the science of the chemical basis of life (Gk bios "life"). The cell is the structural unit of living systems. Thus, biochemistry can also be described as the science of the chemical constituents of living cells and of the reactions and processes they undergo.

Pharmacology and pharmacy rest on a sound knowledge of biochemistry and physiology; in particular, most drugs are metabolized by enzyme-catalyzed reactions. Poisons act on biochemical reactions or processes; this is the subject matter of toxicology. Biochemical approaches are being used increasingly to study basic aspects of pathology (the study of disease), such as inflammation, cell injury, and cancer. Biochemistry and medicine are intimately related. Health depends on a harmonious balance of biochemical reactions occurring in the body, and disease reflects abnormalities in biomolecules, biochemical reactions, or biochemical processes. One major prerequisite for the maintenance of health is that there be optimal dietary intake of a number of chemicals; the chief of these are vitamins, certain amino acids, certain fatty acids, various minerals, and water. Because much of the subject matter of both biochemistry and nutrition is concerned with the study of various aspects of these chemicals, there is a close relationship between these two sciences.

Biomolecules to Cells

Biomolecules can be looked at in two major categories: Small molecules and macromolecules. The small molecules are going to be either metabolites or monomers from which the macromolecules are built. The "inorganic" (sometimes called mineral) molecules and molecular ions: oxygen , water, carbon dioxide ,ammonia, nitrate ion, nitrogen ,phosphate ion and sulphate ion .These are mostly metabolites, though the ions can also serve as counter ions along with chloride in creating the intracellular media. These molecules and ions In turn can be made into metabolites, small organic molecules used in energy transformation and as precursors to monomers and macromolecules.

This book has been written for ME/M.TECH/BE/B.Tech students of All University with latest syllabus for All Department especially Chemistry Department.

The basic aim of this book is to provide a basic knowledge in Bio Chemistry for engineering students of UG and PG degree, diploma & AMIE courses and a useful reference for these preparing for competitive examinations. Also it is very useful for Arts and Science Students.

All the concepts are explained in a simple, clear and complete manner to achieve progressive learning.

This book is divided into five chapters. Each chapter is well supported with the necessary illustration practical examples.