Molecular Biology is the Study of biology at a molecular level. The field overlaps with other areas of biology and chemistry, particularly genetics, Biochemistry and biotechnology. Molecular biology chiefly concerns it self with understanding the interactions between the various systems of a cell, including the interactions between DNA, Rna and protein biosynthesis and learning how these interactions are regulated. The book describes key cell biology concepts needed to study molecular biology, and presents the key concepts of molecular biology necessary for various Fields of biosciences. The book explores the basic concepts of Molecular Biology of the Cell with current understanding of cell biology and intriguing implications and possibilities of that which remains unknown. The book includes the chapter like, Cell, Cell Theory, Molecular Biology and Biochemistry. Historical Development, Origin of Life, Cell Types and Diversity, How Cell is Studied, Microscopy, Chemistry of Cell, Organic Components (Proteins, Carbohydrates, Lipids, Nucleic Acids : DNA, RNA, and Enzymes), Cell Membrane Structure and Functions, Cell Surface and Cellular Interactions, The Cytoskeleton, Mitochondria and Cell Energetics, Plastids and Chloroplasts, Endoplasmic Reticulum, Golgi Complex, Lysosomes, Ribosomes, Centrioles, Interphase Nucleus, Prokaryotic 'chromosome, Plasmids, Cosmid, IS Elements, Transpones and Retroelements, Eukaryotic Chromosome, Cell Cycle : Molecular Basis, Mitosis, Meiosis, Reproduction : Germ Cells, Fertilization, Parthenogenesis and Apomixis, Basic Concepts of Genetics, Metabolism (Carbohydrates, Protein, Lipids, Nucleic Acid, Inborn Errors), Cytoplasmic Inheritance, Linkage and Crossing over in Diploid Organisms, Sexuality and Recombination In Bacteria and Viruses, Mutation (General Concepts, The Molecular Basis, Variation In 'chromosome Number and Structure, in Microorganisms, Inheritance), The Gene, Gene Expression, Gene 'cloning And Recombinant Dna Technology, DNA Fingerprinting, Expression of Induced Genes, Gene Silincing and Antisense Technology, Genetic Engineering Techniques, Gene Therapy, Immunology and Serology, Hybridoma Technology and Monoclonal Antibodies, Cellular Aging and Senessence and Neoplasia with clear and concise concept headings introduce each section.