Applied biochemistry called biological chemistry, is the study of chemical process within and relating to living organisms. Animal Biochemistry is the study of different chemical reactions going on in the body of animal for life. Plant biochemistry is not only an important field of basic science explaining the molecular function of a plant, but is also an applied science that is in the position to contribute to the solution of agricultural and pharmaceutical problems. . Plant biochemistry consists of the chemical elements of which plants are constructed—principally carbon, oxygen, hydrogen, nitrogen, phosphorus, sulfur, etc. Molecular biology concerns the molecular basis of biological activity between the various systems of a cell, including the interactions between the different types of DNA, RNA and proteins and their biosynthesis, and studies how these interactions are regulated. Genetics is the study of genes, heredity, and genetic variation in living organisms. It is generally considered a field of biology, many of the life sciences. Molecular Enzymology deals with enzymes, enzymes are macromolecular biological catalysts. Enzymes accelerate, or catalyze, chemical reactions. Metabolism is the set of life-sustaining chemical transformations within the cells of living organisms. Immunology is a branch of biomedical science that covers the study of all aspects of the immune system in all organisms. It deals with the physiological functioning of the immune system in states of both health and diseases malfunctions of the immune system in immunological disorders.