BIOS 242 Midterm EXAM QUESTIONS AND ANSWERS WITH COMPLETE LATEST UPDATE 2025

BIOS 242 Midterm EXAM QUESTIONS AND ANSWERS WITH COMPLETE LATEST UPDATE 2025 Leave the first rating Terms in this set (194) birth of biotechnology or industrial microbiology mid 19th century, pasteurs investigations into the cause of fermentation led to discovery that yeast can grow with or without oxygen, and that bacteria ferment grape juice to produce acids, whereas yeast cells ferment grape juice to produce alcohol. biotechnology microbes are intentionally manipulated to manufacture products. pasteurization the use of heat to kill pathogens and reduce the number of spoilage microorganisms in food and beverages. 1897 eduard buchner demonstrated process of enzymes and began the field of biochemistry and study of metabolism enzymes cell produced proteins that promote chemical reactions such as fermentation. metabolism sum of all chemical reactions in a organism. germ theory of disease pastuers discovery that bacteria are responsible for spoiling wine led to hypothesis that microorganisms are responsible for causing diseases. today we know diseases are caused by other things like genetics toxins and allergies, so germ theory really only applies to infectious disease. pathogens microorganisms that cause specific diseases etiology study of causation of disease. dominated by Robert Koch Robert Koch search for disease agents such as bacteria responsible for anthrax, developed techniques to isolate bacteria, stain cells, estimate population size, sterilize growth media, transfer bacteria between media, achieved first photomicrograph of bacteria. His greatest achievement was Kochs Postulates. Koch's postulates in his publications on TB, he elaborated on a set of steps that must be taken to prove the cause of any infectious disease: 1- The suspected causative agent must be found in every case of the disease and be absent form healthy hosts. 2- The agent must be isolated and grown outside the host. 3- When the agent is introduced to a healthy susceptible host,the host must get the disease. 4- The same agent must be found int he diseased experimental host. Christian Gram in 1884 Gram developed staining technique using a series of dyes that leave some microbes purple and some pink. Still is most widely used staining technique today. Distinguishes gram positive from gram negative bacteria and reflects differences in composition of bacterial cell wall. Semmelweis hypothesized that cadaver particles on med students hands are what caused puerpural fever and deaths of women giving birth. Had them wash their hands in chlorinated lime water before attending births and the number of deaths from puerpural fever dropped the next year. infection control and epidemiology 2 branches of microbiology, epidemiology=study of the occurrence, distribution, and spread of disease in humans. immunology stuyd of the bodys specific defenses against pathogens. began with experiments of edward Jenner Edward Jenner showed that vaccination with pus collected from cowpox lesions prevented smallpox. Pastuer later built on Jenners work to develop vaccines against fowl cholera, anthrax, and rabies. Chemotherapy, Paul erlich Branch of medical microbiology in which chemicals are studied for their potential to destroy pathogenic microorganisms. Began with Paul erlich who searched for a "magic bullet" that would kill microoganisms but would be nontoxic to humans. He discovered chemicals effective against the agents that cause sleeping sickness and syphilis. Biochemistry study of metabolism. Kluyver and Niel proposed biochemical reactions are shared by all living things, are few in number, and involve the basic transfer of electrons and hydrogen ions. Microbial genetics microbial genetics=study of inheritance in microorganisms. A genes activity is related to the function of the specific protein coded by that gene. We now know the exact way in which genetic info is translated into a protein. Molecular biology combines aspects of biochemistry, cell biology, and genetics to explain cell function at a molecular level. Particularly concerned with genome sequencing. Genetic engineering the manipulation of genes in microbes, plants and animals for practical applications such as development of pest resistant crops and the treatment of disease. Gene therapy use of recombinant DNA (DNA composed of genes from more than one organism) to insert a missing gene or repair a defective gene in human cells. environmental microbiology studies the role microorganims play in their natural environment. Microbial communities play an essential role in decay of dead organisms and recycling of chemicals such as carbon nitrogen and sulfur. Environmental microbiologists also limit the abundance of pathogenic microbes int eh environment, such as water purification and sanitation.