Microbiology

Microbiology Study Guide

the microorganism in the body through transmission of the lymphatic system. Disinfectants destroy the organisms living on non-living substances. Antiseptics can be categorized as either true germicides or bacteriostatic. The former is used to destroy the microbes while the latter puts a restriction on the growth of the microbes. The antiseptics that are capable to act against bacteria are known as antibacterials, while the microbicides that act against viruses are known as viricides, or antivirals. Sanitation The prevention of human contact with wasteful hazards is known as sanitation. These hazards can be the agents of disease and can be physical, microbiological, biological, or chemical in nature. Waste has the ability to cause infections and diseases. Waste can be feces of animals or humans, solid waste, industrial, domestic, or agricultural wastewater, or other wastes. Some ways to promote sanitation are recycling and engineering solutions like wastewater treatment, personal hygiene (handwashing), using sanitizer, or by incorporating simple hygienic technologies like building septic tanks and latrines. Antibiosis The biological interaction between two or more organisms that causes a threat to at least one of them is known as the process of antibiosis. It is also associated with the antagonistic relationship between the metabolic substances generated by one of the organisms onto the other. An example of antibiosis is the relationship between an organism causing infection in the body and an antibiotic. In this instance, one of the organisms causes threat or kills the other one. Further, the relationship between the human body and infection-causing bacteria is also an instance of antibiosis. In this case, when the person suffers from infection, he is the harmed organism. Antibiosis is studied mostly in relation of host plants and the insects that feed on them. Chemotherapy The treatment of cancer using antineoplastic drugs is termed chemotherapy. This therapy kills those infectious cells that divide and grow rapidly. These cells generally harm the other cells that are produced in the bone marrow, digestive tracts, and hair follicles under normal circumstances. Common side effects of chemotherapy are: • Myelosuppression: The fall in the production of blood cells • Mucositis: Occurs when the lining of the digestive tract gets inflamed • Alopecia: Leads to hair loss Physical Methods of Control Physical methods of control can be subdivided into heat and non-heat methods. The terms used to define the physical methods of control are thermal death time and thermal death point. Thermal death point is the lowest temperature on which all the microorganisms are killed, while thermal death time is the minimum time, at a given temperature, needed to kill the microorganisms. Another term,

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