Biotech EOPA 2 part 2 - Bacteria Cultures & Gram Staining

bacillus

Rod shaped bacteria

coccus

A spherical bacterium.

spirillus

spiral shaped bacteria

Streptococcus pyogenes

strep throat

Staphylococcus aureus

a form of staph infection that commonly infects wounds and causes serious problems such as toxic shock syndrome or produces food poisoning

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where to you label petri dishes for bacterial cultures

upside-down

how do you incubate bacterial cultures in petri dishes

Isolate Colonies

The purpose of streaking a plate

Cool to the Touch

When do you add ampicillin to agar when making amp plates (roughly 50 degrees C).

Serial Dilution

Used to dilute a population to create a standard curve that can be used to estimate the population of an unknown sample.

cell wall

gram staining bacteria is based on the composition of the cell wall

gram +

thick peptidoglycan layer, purple

gram -

Thin peptidoglycan layer, pink

step 1 gram stain

crystal violet (gram + purple stain)

Step 2 Gram Stain

Mordant (iodine ) to fix/set dyes

Step 3 Gram Stain

Decolorization; alcohol (ethanol), removes crystal violet

Step 4 Gram Stain

Safranin (gram - Red Stain)