Term
|
Definition
Exact composition ratio of media is known
-inorganic broths- lacks good carbon source
-glucose salts broth- glucose as only carbon source |
|
|
Term
|
Definition
Made from plant or animal tissue extract- exact amounts are unknown- good source of organic compounds (sugar, AA's vitamins, minerals)
-nutrient broth
-yeast extract broth |
|
|
Term
| What does a spectrophotometer check? |
|
Definition
| Turbidity- cloudiness- amount of bacterial growth |
|
|
Term
| Disadvantages of Spectrophotometer |
|
Definition
| Doesn't differentiate between living and dead cells. Requires incubation, prone to human error (pipetting) |
|
|
Term
| advantages of Spectrophotometer |
|
Definition
| instant reading, more quantitative measurement than using your naked eye to approximate cloudiness. |
|
|
Term
|
Definition
| Carbon source is from organic molecules |
|
|
Term
|
Definition
| Carbon source is from inorganic molecules- CO2 |
|
|
Term
|
Definition
| energy is obtained from chemical reactions (redox)- inorganic and organic chemicals |
|
|
Term
|
Definition
| energy is obtained from light |
|
|
Term
| For carbohydrate fermentation, what media and pH indicator were used to identify fermentation? |
|
Definition
| media was nutrient broth with phenol red |
|
|
Term
| what were the three sugars used to measure carbohydrate fermentation? |
|
Definition
| lactose, glucose, sucrose |
|
|
Term
| Which bacteria showed acid production with no gas formation? (yellow) |
|
Definition
|
|
Term
| Which bacteria had acid and gas productions (yellow with bubble)? |
|
Definition
|
|
Term
| Which bacteria had no fermentation (no acid or gas)? |
|
Definition
| A. faecalis and Pseudomonas |
|
|
Term
|
Definition
| selects among a specific groups of bacteria- usually share common trait (gram positive, gram negative, halophiles) |
|
|
Term
| 3 types of selective Media |
|
Definition
-Crystal Violet Agar
-Phenylethyl Alcohol Agar
-7.5% Sodium Chloride Agar |
|
|
Term
Phenylethyl Alcohol Agar
(what does it inhibit, what does it select for) |
|
Definition
Inhibits Gram negative (alcohol disrupts membrane)
Selects for Gram Positive cocci |
|
|
Term
Crystal Violet Agar
(what does it inhibit, what does it select for) |
|
Definition
Inhibits Gram Positive
Selects for Gram Negative |
|
|
Term
7.5% Sodium Chloride Agar
(what does it inhibit, what class of bacteria does it select for, give an example of a bacteria in this class) |
|
Definition
inhibits anything non-halophilic
Selects for halophiles
Ex: Staphylococcus |
|
|
Term
|
Definition
| Selects specific organism within a group of bacteria (identifies species) |
|
|
Term
| 3 types of Differential Media |
|
Definition
-Mannitol Salt Agar
-MacConkey Agar
-Eosin-Methylene Blue Agar |
|
|
Term
Mannitol Salt Agar
(What group does it select for, what does it differentiate and how, provide examples) |
|
Definition
salt selects for halophiles- Staphylococcus
Mannitol fermentation (pathogenic trait) differentiates epidermidis from aureus
Ex: S. aureus ferments mannitol and turns red media yellow |
|
|
Term
MacConkey Agar
(What group does it select for, what does it differentiate and how, provide examples) |
|
Definition
Selects for gram negative (crystal violet inhibits gram positive)
Differentiates lactose fermenting bacteria (coliforms)
Lactose fermentation produces acids which turn the pH indicator red
Ex: E. coli, citrobacter, Enterobacter, Klebsiella |
|
|
Term
Eosin-Methylene Blue Agar
(What group does it select for, what does it differentiate and how, provide examples) |
|
Definition
Selects for gram negative lactose fermenters (coliforms)
Differentiates between E. coli and all other coliforms- E. coli produces metallic green color
-Enterobacter aerogenes (coliforms)- pink colonies w central dark purple spot |
|
|
Term
|
Definition
Contain nutrients to support a wide variety of bacterial growth as well as additional unique requirements of fastidious growers
Ex: blood agar |
|
|
Term
Blood Agar
(what does it differentiate? what are the three types of growth?) |
|
Definition
Differentiates hemolytic Streptococcus species (enriched and differential media)
1. Alpha hemolysis
2. Beta hemolysis
3. Gamma hemolysis |
|
|
Term
Alpha hemolysis
(what does it look like and what organism shows this type of growth?) |
|
Definition
Partial breakdown of hemoglobin shows green/light brown sheen around colonies (biliverden)
Ex. E. coli |
|
|
Term
Betta hemolysis
(what does it look like and what organism shows this type of growth?) |
|
Definition
Full breakdown of red blood cells leaves clear space- lyse cells using beta-hemolysin (streptolycin)
Ex: S. pyogenes |
|
|
Term
Gamma hemolysis
(what does it look like and what organism shows this type of growth?) |
|
Definition
no hemolysis- whitish grey sheen on surface of media
Ex: S. epidermidis |
|
|
Term
| Enteric Bacteria (2 types) |
|
Definition
Bacteria that colonize the intestinal tract- coliform and non-coliform
-ferment glucose
-facultative anaerobes
-usually gram negative bacilli |
|
|
Term
|
Definition
lactose fermenting enterics
Ex: E. coli, citrobacter, Enterobacter, Klebsiella |
|
|
Term
|
Definition
non-lactose fermenting enterics
Ex: Salmonella, Shigella, serretia, proteus |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Alpha Hemolysis (Blood Agar) |
|
|
Term
|
Definition
| Betta Hemolysis (Blood Agar) |
|
|
Term
|
Definition
| Gamma Hemolysis (Blood Agar) |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Eosin Methylene Blue Agar (E. coli) |
|
|
Term
|
Definition
| Eosin Methylene Blue Agar (Enterobacter Aerogenes) |
|
|
