Culture and Sensitivity Flashcards
What is a prokaryote?
Unicellular organism that lacks organelles and membrane bound structures
What are the 4 requirements for a prokaryote to live?
Temperature, ph, oxygen, nutrients
What prokaryotes need oxygen?
Obligate anaerobe
What prokaryote can survive in oxygen but growth is limited?
Facultative anaerobes
Which prokaryote needs oxygen, cannot ferment but will die in high amounts of oxygen?
Microaerophilic
What is capnophilic?
Requiring high amounts of carbon dioxide.
What is the ideal prokaryotic ph?
6.5-7.5
What are 4 methods of IDing prokaryotes?
Size, shape (coccus, bacillus, spirilli, pleomorphic), arrangement (single, pairs, chains, tetrads, clusters, palisades), chemical reactivity
What are the 4 stages of bacterial growth?
Initial, exponential, stationary, final
What are fungi?
Filamentous strands of cells that secrete enzymes and feed on the organic material they grow on.
Fungi are either:
parasitic or saprophytic (uses decaying material as energy)
How does yeast reproduce?
Asexual budding
Which need living cells to survive, virus or bacteria?
Virus
What is selective grow media and an example?
Allows one specific bacteria to grow. MacConkey agar
What is enrichment grow media?
Inhibits growth of some organisms while promoting likely pathogens
What is nutrient rich grow media?
Allows most bacteria to grow, blood agar
What is differential grow media?
Contains indicator that allows user to ID and differentiate organisms
Which agar contains both differential and enrichment media?
Blood agar
What is the most common agar?
Trypticase soy agar with sheep blood
What are the 4 types of hemolysis? Describe each.
Alpha, beta, gamma, delta. Alpha is partial hemolysis with green/slimy discoloration. Beta is complete hemolysis with a clear zone around the colony. Gamma is hemolysis that produces no change in medium. Delta has double zone hemolysis, both alpha and beta
MacConkey medium grows what?
Gram negative bacteria. Lactose producing bacteria turn pink.
If there is growth on MacConkey but growth on Blood agar, what bacteria is growing?
Gram positive
THIOGLYCOLLATE BROTH is a common liquid medium used for which bacteria?
Anaerobic
Triple sugar iron is used to grow which bacteria?
Gram negative enterobacteria like salmonella, e.coli, which ferment glucose and become acidic
What does SLANT and BUTT detect?
SLANT detects utilization of lactose and sucrose, BUTT detects glucose fermentation
In the triple sugar iron test, acidic and alkaline changes are what color?
Acidic are yellow, alkaline are red
How are agar plates/jars disposed of?
Add dilute bleach or chlorhex, seal container and let sit 4-5 minutes, then trash.
What things are the most commonly cultured?
Blood, urine, spinal fluid, joint fluid, milk, solid organs, respiratory tract
