CHAPTER 2 - BACTERIAL GROWTH AND FACTORS AFFECTING BACTERIAL GROWTH

Abstract

This chapter discusses the bacterial growth and factors affecting bacterial growth. The bacterial cell has been considered as a single entity; normally, cells are seen collectively as aggregations of many cells on a solid medium which are known as bacterial colonies or in liquid culture conferring turbidity on an originally optically clear medium. The morphology of bacterial colonies is of importance in systematic bacteriology. The chance cultivation of microorganisms had occurred long before their nature or existence was proved; their growth in carbohydrate-containing media. However, for practical study in the laboratory, an array of culture media have been evolved, some designed to grow all types of bacteria, others to select from a mixed environment a particular bacterial species. Most culture media used routinely are based on the products made from meat extracts or digests. There is, for each bacterial species, a set of interrelated conditions which give optimum growth. These conditions are: the supply and balance of solid nutrients, the supply of gaseous nutrients, hydrogen ion concentration, temperature, osmotic pressure, and the presence of water.