lesson 6 smear preparation

smear

wet mount

two ways to prepare a specimen to be observed under a light compound microscope

smear

preparation process where a specimen that is spread on a slide

wet mount

preparation process where a live specimen in culture fluid is placed on a concave glass slide or a plane glass slide

basic stains

are cationic and have positive charge

ideal for staining chromosomes and cell membranes of many bacteria

methylene blue

crystal violet

safranin

malachite green

common basic stains

acid stains

used to identify bacteria that have a waxy material in their cell walls

this form of staining differentiates bacteria

simple and differential

two types of stains

simple stain

has a simple basic dye that is used to show shapes of cells and the structures within a cell

differential stain

consists of two or more dice and is used in the procedure to identify bacteria

gram stain and the zehl nelson acid fast stain

commonly used differential stains

hans christian gram

a danish physician develop the gram stain

gram stain

a method for the differential staining of bacteria

gram positive microorganisms stain purple and gram negative microorganisms stain pink

staphylococcus aureus

the gram positive that is a common bacterium that causes food poisoning

ziehl neelsen acid fast staining

developed by franz ziehl and friederick neelsen

ziehl neelsen acid fast staining

a die that attaches to the waxy material in the cell walls of bacteria such as mycobacterium tuberculosis

mycobacterium tuberculosis

a bacterium that causes tuberculosis

mycobacterium leprae

mycobacterium which causes a leprosy

nigrosin and india ink

special stain used as negative stain

schaeffer fulton endospore stain

special stain used to colorize the endospores

endospores

a dormant part of the bacterial cell that protects the bacteria from the environment outside the cell

simple staining

use a single dye

it demonstrates the size, shape, and arrangement of cells

examples of methylene blue and crystal violet

differential staining

uses two or more dyes to distinguish different types or different structures of bacteria

differential staining

cute distinguishes gram positive or gram negative and it distinguishes the member of mycobacteria and nocardia from other bacteria

special staining

this stains identifies specialized structures and it exhibits the presence of flagella