Quiz 1, Ch. 1, 2, 3, 4 Flashcards
What important contributions did Edward Jenner make toward microbiology?
created first immunization
What important contributions did Joseph Lister make toward microbiology?
aseptic techniques: decreased wound infections, carbolic acid on bandages to reduce infection
What important contributions did Robert Koch make toward microbiology?
Koch’s postulates: whether an organism was pathogenic and what disease it caused
What important contributions did Louis Pasteur make toward microbiology?
germ theory of disease
Staphylo looks like
a cluster
Coccus looks like
round ball
Strepto looks like
chain
bacillus looks like
rod shaped
spirillum looks like
spiral
What are bacteriophages?
viruses that infect and kill bacteria
Why are bacteriophages important?
antibiotic resistance, they are receptor specific and leave good bacteria alone
How do you calculate total magnification?
ocular lens x objective lens
When would we want to use a wet mount vs a smear?
wet mounts: to view living organisms and observe motility; ex. hanging drop technique
smear: used to view killed organisms
What is heat fixation and why is it important?
a slide is passed through an open flame several times.
kills the organism, adheres it to the slide, alters it to readily accept stains
Gram stain first step:
crystal violet is added to the slide for one minute and stains all cells purple; rinse w water
Gram stain second step:
Gram’s iodine add for 1 min: acts as mordent
How does the mordent in a Gram stain affect Gram positive and Gram negative differently?
It will trap the purple dye firmly into the thick wall of the Gram positive cell and only loosely associate into the Gram negative cell
Gram stain step 3
application of alcohol dissolves lipids in the outer cell membrane of negative cell and removes the dye from the peptidoglycan layer; rinse w water
Gram stain step 4
stain w safranin; the Gram negative cell will stain pink
Concise version of the Gram stain
Fixation, Crystal violet, Iodine treatment, Decolorization, Counter stain safranin