Observing Bacteria and Blood
Cynthia Alonzo, M.S. Version 42-0249-00-01
Lab Report Assistant This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor.
Exercise 1: Viewing Prepared Slides
A.…show more content…
The thickness of glass that covers the specimen slide also affects the ability one has to focus the image. If the glass is too thick for the objective lens then one will have a difficult time getting a focused view (Alonzo p55).
The resolution in microscopy terms refers to the numerical aperture of the objective lens. The higher the numerical number the better the resolution of the image; also the shorter the wavelength the better the resolution (Alonzo p55).
Contrast is directly related to the illumination system and can be adjusted by changing the intensity of the light and the diaphragm. Chemical stains applied to the specimen can also enhance contrast elements (Alonzo p56)
B. What is the purpose of immersion oil? Why does it work?
The purpose of using immersion oil is to help view bacteria that would not be able to not be seen otherwise. The immersion oil that is put on the slide between the objective and the slide to prevent the loss of light because of bending light rays as they pass through the air. The oil in turn enhances the resolving power of the microscope. (Alonzo p62).
Exercise 2: Observing Bacteria Cultures in Yogurt Questions A. Describe your observations of the fresh yogurt slide.
The yogurt slide had small particles that were constantly moving. They were small and round like the Cocci form of bacteria as well.
B. Were there observable differences between your fresh