Microbiology-Lab 1 Exam Questions and Answers | 100% Pass

Microbiology-Lab 1 Exam Questions and Answers | 100% Pass BSL -Answer-Bio-safety Levels, the classification of microbes BSL-1 -Answer-"Organisms that don't typically cause disease" & are a minimal threat. Standard microbiological practices are adequate. They can be handled out in the open with no special equipment required. Examples are Bacillus subtilis & E. coli BSL-2 -Answer-Organisms encountered commonly in the community, "they present a moderate threat" of environmental and/or health hazard. They're associated with a variety of human diseases, most can be successfully treated if identified in a timely manner. Infectious routes are inhalation or penetration of the skin. Standard microbiological practices are adequate with the addition of a biological safety cabinet in case of splashes or aerosol. Examples are Salmonella, S. aureus & C. dificile BSL-3 -Answer-Organisms of local or exotic origin & are associated w/respiratory transmission & serious or lethal diseases where treatment and/or vaccines aren't available. Special ventilation systems are used & access to the lab is restricted & "not handled on the open bench". Examples are B. anthracis, M. TB & West Nile Virus BSL-4 -Answer-"Organisms w/great potential for lethal infection". Inhalation, exposure to infectious droplets & autoinoculation are of primary concern. The lab is isolated off & access is controlled. One-piece body suits w/a life support system, are worn. Examples are Ebola virus, Marburg virus & Lassa fever Free-Living -Answer-Microorganisms that don't reside on or in a specific plant or animal host & are not known to cause disease Pathogens -Answer-Microorganisms that cause disease Microscope -Answer-An optical instrument used for viewing very small objects, such as animal or plants cells, typically magnified several hundred times Condenser Lens -Answer-Located above the light source & under the specimen. It focuses the light on the specimen Objective Lenses -Answer-The primary lenses of the microscope and they provide the majority of the image enhancement. Our microscopes have 4X, 10X, 40X & 100X Refraction -Answer-The 'bending" of light as it passes through the objective lens Virtual Image -Answer-The real image is magnified by the ocular lens to produce the virtual image seen by your eye Resolution -Answer-Clarity of an image Limit of Resolution -Answer-A measurement of how far apart two points must be for the microscope to view them as being separate Numerical Aperture -Answer-The measure of a lens's ability to "capture" light coming from the specimen & use it to make the image Dark-Field Microscopy -Answer-A special condenser used so only the light reflected off the specimen enters the objective Phase Contrast Microscopy -Answer-A contrast-enhancing technique used to produce high-contrast images of transparent specimens, such as living cells or microorganisms Fluorescence Microscopy -Answer-The sample you want to study is the light source. The technique is used to study specimens, which can be made to fluoresce Control -Answer-The component in an experiment that never changes, in order to receive accurate results