Micro Lab 1 Exam

What bacteria is this

E. coli

Proper pour plate

Method used to isolate and count viable microorganisms by mixing a diluted liquid sample with cooled molten agar in a sterile Petri dish

Is this a countable plate?

No, TFTC indicates Too Few To Count, meaning the number of colonies (30) is less than the minimum needed.

Is this a countable plate?

No, TMTC indicates Too Many To Count, meaning the number of colonies (300+) is more than the maximum needed.

Is this plate countable?

Yes, it is between 30-300 colonies

What is this called

Colony counter

What is this called

Spectrophometer

% transmittance

amount of light passing through a substance

Optical density

how dense a substance is

Rheostat

(on switch) controls power to bulb

Iris

Controls amount of light to specimen

Total Magnification

Ocular x objective

Oil immersion

Reduces refraction

Staphylococcus aureus transmission route

Human to human contact, aerosols

What type of organism is Staphylococcus aureus

Bacteria

Bacillus anthracis transmission route

Contact with wool or goat hair, contaminated meat

What type of organism is Bacillus anthracis

Bacteria

Klebsiella pneumoniae transmission route

Aerosol droplets

What type of organism is Klebsiella pneumoniae

Bacteria

Corynebacterium diphtheriae transmission route

Aerosol droplets

What type of organism is corynebacterium diphtheriae

Bacteria

Treponema pallidum transmission route

Sexual contact

What type of organism is treponema pallidum

Bacteria

Rhizopus nigricans transmission route

Aerosols

What type of organism is rhizopus nigricans

Fungus

Aspergillus niger

Spore aerosol

What type of organism is Aspergillus niger

Fungus

What type of organism is Penicillium notatum

Fungus

What organism is this

Staphylococcus aureus

What organism is this

Bacillus anthracis

What organism is this

Klebsiella pneumoniae

What organism is this

Cornybacterium diphtheriae

What organism is this

Treponema pallidum

What organism is this

Rhizopus nigricans, asexual sporangium

What organism is this

Rhizopus nigricans, sexual zygospore

What organism is this

Aspergillus niger

What organism is this

Penicillium notatum

What does staining do

Adds contrast

What is simple staining

Single dye to color a specimen, making cells visible and distinct from their background

What is differential staining

Two or more chemical dyes (decolorizer and mordant) to distinguish between different types of microorganisms or specific cellular structure

Simple- Positive stain

Basic dye: stains organism

Simple- Negative stain

Acidic dye: stains background

Differential- Gram stain

Stains cell wall structure

Differential- Gram positive stain

Has thick PG

Differential- Gram negative stain

Has thin PG

Differential- Endospore stain (green)

See dormant, highly resistant bacterial endospores

Differential- Vegetative stain (pink)

See bacterial active stains

Simple positve stain examples

Methylene blue, crystal violet

Simple negative stain example

India ink

Differential stain steps

Must create smear first: primary stain, mordant, decolorizer, counter stain

Gram stain steps

Crystal violet, iodine, alcohol, safranin

Endospore stain steps

Malachite green, heat/steam, water, safranin

Smear steps

Draw circle, add water, add bacteria, air dry, and heat fix

How to properly, incubate, lable and inoculate broths, agar petri dishes, agar tubes

Label bottom of plate, incubate agar side up, proper sterilization of loop, hold tube with non-dominant hand and cap with dominant hand with ring and pinky finger

Aseptic technique

Set of specific practices and procedures used to prevent the contamination of cultures, sterile media, and the surrounding environment by unwanted microorganisms

Primary containment

Protects laboratory personnel and the immediate workspace from exposure to infectious agents

Secondary containment

Protects the outside environment and the surrounding community from release

BSL

Set of containment practices, safety equipment, and facility designs used to safely manage biological agents

PPE

Specialized gear worn to shield workers from infectious agents, biohazards, and chemical splashes

Transient organisms

Organisms that come and go from the body

Resident organisms

Organisms that inhabit the body on a regular basis

What diseases are caused by staphylococcus aureus

Toxic shock syndrome, food poisoning

What disease is caused by bacillus anthracis

Anthrax

What diseases are caused by klebsiella pneumoniae

Pneumonia, urinary tract infections

What disease is caused by corynebacterium diphtheriae

Diphtheria

What disease is caused by treponema pallidum

Syphilis

What disease is caused by rhizopus nigricans

Allergies

What disease is caused by aspergillus niger

Aspergillosis otomycosis

What disease is caused by penicillium notatum

None

Obligate aerobe

Requires oxygen to survive

Obligate anaerobe

Must have oxygen free environment

Facultative anaerobe

Can survive with or without oxygen

Aerobic respiration causes build up of what

Peroxide and superoxide

What is fluid thioglycollate for

Testing aerobic and anaerobic in tubes

What is is anaerobe jar for

Plates

Where would growth be located at in obligate aerobe tube

Top

Where would growth be located at in micro-aerophile tube

Middle

Where would growth be located in obligate anerobe tube

Bottom

Where would growth be located in facultative anerobe

Spread all throughout

Fungal spores

Reproductive

Endospores

Survive in harsh conditions

Asepsis

state of being free from disease-causing microorganisms

Pipette

a narrow tube instrument used to measure and move exact volumes of liquid

Pipette dispenser

used to automatically measure and dispense precise volumes of liquids.

Pour plate

Technique used to isolate and count viable organisms in liquid samples

Agar

Jelly-like substance made from algae that is used as a solidifying agent

Media

A solid, liquid, or semi-liquid substance containing nutrients designed to support the growth, proliferation, and survival of microorganisms

Petri dish

Lidded dish used to culture microorganisms

Microbiome

Community of tiny living organisms that live together in a specific environment

What does EMB agar test for

Gram negative enteric rods and lactose fermenters

Common diseases spread through feces

Norovirus, Hepatitis A

Why is it important to protect against fecal contamination

Feces carry many germs that can cause life threatening diseases

Colony

A visible cluster of microorganisms growing on/inside medium

Fomite

Inanimate objects that harbor microorganisms

Ubiquity

Being in many places simultaneously or everywhere at all times

Inoculum

Small amount of microorganism sample that is introduced into a fresh culture medium to start a new population of growth

Media

Liquid, solid, or semi-solid nutrient solutions used to grow, and isolate microorganisms

What is TSA medium

Rich medium that supports the growth of many kinds of microorganisms

Why do some bacterial samples incubate at 37 celcius

This temperature matches normal human body temperature

Why do some bacterial samples incubate at 25 celcius

Their natural environments or optimal growth conditions match that cooler range rather than human body temperature