ACTIVITY 2: SIMPLE STAINING METHOD Flashcards
Live microorganisms, particularly ______ and ______, are almost ______ and do not show contrast with the ______ or the ______ with which they are usually suspended it wet amounts or hanging drops. For this reason, they are usually ______ to make them more visible, and sometimes, even give more definition to specific structures.
bacteria, fungi, colorless, medium, diluent, stained
______ are dyes, mostly ______, which consist of ______ and ______ charged ions. One part of the dye molecule is colored and is called the ______.
Stains, salts, negatively, positively, chromophore
______, a basic dye, reacts with the ______ components of cells, such as ______ and some ______.
Methylene blue, negatively-charged, nucleic acids, polysaccharides
Fixation of smear and staining
Bacterial cells from a sample are fixed by smearing a small amount of sample onto a slide and fixing it by ______. This process “______” the bacteria into the slide to make it more ______ in preparation for staining.
heating, fixes, permanent
Fixation of smear and staining
______ involves the coloration of bacteria with the application of a single dye solution to a fixed smear.
Simple staining
______ and ______ are the most commonly used simple stains.
Crystal violet, methylene blue
Heat fixation served three primary purposes:
- it kills the bacteria
- it adheres the cells to the slide
- it preserves the overall structure of the cell
Heat fixation served three primary purposes
______
- making them safer to handle
it kills the bacteria
Heat fixation served three primary purposes
______
- preventing them from being washed away during the staining process
it adheres the cells to the slide
Heat fixation served three primary purposes
______
- by coagulating proteins
it preserves the overall structure of the cells
______ ensures that the bacterial morphology remains intact for observation under the microscope.
Heat fixation
______ the smear before heat fixation prevents the cells from ______ due to rapid ______ of water.
Drying, bursting, evaporation
If the smear is still wet, the sudden exposure to ______ can cause the remaining moisture to ______, leading to cell ______ and ______.
heat, boil, lysis, distortion
Proper ______ ensures that the bacterial cells remain intact and can be fixed effectively without altering their ______ or ______.
drying, shape, structure
______ can severely damage the bacterial cells, causing them to shrink, distort, or even burn. This can make it difficult to observe their natural ______ and ______ under the microscope.
Overheating, shape, arrangement
Excessive ______ can destroy certain cellular structures, reducing the quality of the staining and making it harder to identify important features.
heat
______ is a basic dye that interacts with the ______ charged compounds of bacterial cells, such as ______ and certain ______. This interaction enhances the ______ between the ______ and the ______, making the cells more visible under the microscope.
Methylene blue, negatively, nucleic acids, polysaccharides, contrast, cells, background
Since it stains the cell structures effectively without being overly harsh, ______ is commonly used in ______ methods to observe bacterial ______ and ______.
methylene blue, simple staining, morphology, arrangement
In conclusion, the ______ is an essential technique for observing bacterial morphology under a microscope.
simple staining method
By using a ______ dye, such as ______, the contrast between the cells and the background is enhanced, making it easier to study their shape and arrangement.
single, methylene blue
Proper ______ preparation, including ______ and ______, is crucial to preserving the integrity of the cells and ensuring accurate observations.
smear, drying, heat fixation
This activity highlights the importance of ______ in microbiology, as it allows for better visualization and understanding of microorganisms, which otherwise nearly invisible under normal light microscopy.
staining
