Parasites are usually macroscopic organisms of various genera that infect man, animals and plants, However, our interest in this chapter is on human parasites. The process of examination of clinical specimens for parasites begins with parasite specimen collection. Again, two types of specimens are generally examined. These are fresh specimens and preserved specimens. FRESH SPECIMEN … Read more
Detection of Animal Viruses The presence of viruses in an animal or plant is recognised by the manifestation of some abnormality in whole organisms or host cells. In whole organisms the manifestation of the presence of a virus varies from inapparent infections which may only be detected by the formation of antibodies or by the … Read more
Sometimes, it is necessary to inhibit the activities of microorganisms and at other times to destroy them completely, on a given object or within living tissues. Several methods can be used to achieve these objectives. These include methods in sterilization, Disinfection, Antisepsis and antibiotics. Sterilization This is the process of complete destruction of all microorganisms … Read more
Microbiologists working in the laboratory often have to determine the microbial cell concentration in a given sample and may ‘also compare the amount of microbial growth under various conditions. The enumeration of microorganisms is very important in dairy microbiology, water microbiology, food microbiology as well as in research. In process engineering the knowledge of biomass … Read more
Preservation Of Microbial Cultures Culture handling and storage are very essential in Microbiology. Pure cultures, of microorganisms can be easily contaminated, undergo genetic changes or even die off if not properly handled. Scientists preserve one microorganism or-the other for various reasons. Research scientists trying to characterize microorganisms and identify them need to produce reliable subcultures … Read more
Unstained bacterial cells are nearly always transparent when observed under the light microscope and hence are difficult to see. In wet preparations, due to the closeness of the refractive indices of glass, water anq bacteria, the problem is compounded. To increase the contrast between the bacterium and its surroundings therefore, staining is employed. Most bacteria … Read more