The _______ of a compound light microscope focuses light from the light source on the specimen.
Condenser lens OR condenser
Which of the following is the most convenient and appropriate unit for expressing the size of an average bacterial cell?
Micrometer
All of the following are visible through a compound light microscope except____.
0.02-AUM ribosome
Bacterial motility and flagellar movement can readily be viewed using transmission electron microscopy.
False
A____________ is equal to 0.000001m.
micrometer
Acid-fast Mycobacteria differ from non-acid-fast bacteria by the presence of ____. In the decolorizing step of the acid -fast stain, which reagent is used?
carbol fuchsin waxy material in their cell wall
When stained, bacteria in the genus Mycobacterium are ____. When using a 10x ocular lens and a 40x objective, the total magnification achieved is
acid-fast 400x
Which of the following is not a modification of a compound microscope?
electron microscope
Flagella are too ________ to be seen with the light microscope without adding a mordant.
small or thin
Immersion oil acts to decrease refraction of light rays and thus increase resolution.
True
In the Gram stain, if the decolorizing step is deleted, gram-negative cells will appear _______ at the completion of the staining procedure.
Purple
Magnification is the quality of the microscope that allows on to distinguish between two points that are very close together.
False
Place these structures of the compound light microscope in order that light passes through them on the way to the observer's eyes: (1) condenser,(2)ocular lens, (3) illuminator, (4)specimen, (5) objective lens.
3-1-4-5-2
Response feedback: The path of light begins with the illuminator, then passes through the condenser, the specimen, the objective lens, then then the ocular lens.
Bacterial smears must be heat-fixed before all staining procedures.
False
The ______ charge of a basic dye adheres to the ______ charge of bacterial cell surfaces.
positive;negative
The _____ is the part of the microscope that controls the amount of the light entering the condenser.
diaphragm
The Gram stain is important in medical microbiology because the results help physicians select appropriate antibiotics for treatment.
True
Which of the following kinds of microscopy would be most appropriate for viewing the shape and arrangement of pili or fimbriae on the surface of the bacterial cell?
scanning electron microscopy
Which of the following types of microscopy is most useful for viewing the internal structures of unstained specimens?
Phase-contrast
You are viewing a sputum smear that has been stained with an acid-fast stain. On this smear you see 5-Aum-long red cells. You can conclude that _______.
there are acid-fast bacteria in the specimen