Smear Prep and Simple Stain

Flashcards covering key vocabulary and concepts from the Smear Prep and Simple Stain lecture notes.

Smear Prep

Attaching a microbial sample to a microscope slide for staining.

Fixation

A process to attach or "fix" cells to a microscope slide by gently heating the slide or by chemical means like methanol.

Simple Staining

Cells are stained with a colored dye to make them more visible under the microscope using only one dye to stain all bacterial cells the same color, allowing determination of cell morphology, size, and arrangement.

Chromophore

The charged region of a dye molecule that gives it color and stains bacteria by forming covalent or ionic bonds to the cell.

Basic Stains

Stains with a positively charged chromophore that easily color bacterial cells due to the negatively charged bacterial cell surfaces (examples: methylene blue, crystal violet, and safranin).

What happens if the culture does not air dry before fixation?

The cells will be washed away during staining.

What happens if too much bacteria are in one big clump on the slide?

Too much dye will be concentrated in one area that obscures the morphology and arrangement of the cells.