Recapitulation is a bold and influential idea that is particularly associated with Ernst Haeckel though many other biologists also supported it in the nineteenth and early twentieth centuries. According to the theory of recapitulation, the stages of an organism’s development correspond to the species’ phylogenetic history- in a phrase, “ontogeny recapitulates phylogeny.” Each stage in development corresponds to (that is, [...]
Among the various methods followed for controlling microbial activity, the best by far is sterilization as it eliminates all the microbes. Sterilization is achieved by the following methods: 1. Physical Methods 2. Radiation Methods 3. Ultrasonic Methods 4. Chemical Methods. 1. Physical Methods: Physical methods of sterilization include killing of microbes by applying moist heat as in steaming or dry [...]
In this article we will discuss about:- 1. Meaning of Antimicrobial Action 2. Mechanisms of Antimicrobial Action 3. Effects on on Microbial Cells. Meaning of Antimicrobial Action: Microorganisms can be killed, eliminated or inhibited by a number of physical, chemical and other means. All these agents which act against the microbes are called ‘Antimicrobial agents'. Varieties of microorganisms differ greatly [...]