Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Microbiology
Lab - Biochemical Test (Part 2)
| Question | Answer |
|---|---|
| What is the purpose of the Indole test? | Test to see if organism has tryptophanase (an amino acid that hydrolizes tryptophan) |
| What kind of medium is used for the Indole Test? | 1% tryptone broth |
| What kind of inoculation/incubation is used in the Indole Test? | Loop inoculation |
| What does 1% tryptone broth contain? | tryptophan digestive amino acids |
| What is the chemical reaction when tryptophan gets hydrolized? | Tryptophan + H2O ---- tryptophanase ----> Indole + Pyruvic Acid + Ammonia (NH3) |
| What is the reagent used in the indole test? | P-dimethylaminobenzaldehyde (Kovac's) |
| What is Kovac's reagent use to detect? | the presence of indole |
| What is the color produced when the indole tests results are positive? | RED |
| What is the color produced when the indole test results are negative? | Tan/Greenish |
| What is the purpose of the Urease test? | Test to see if organism has urease enzyme that hydrolizes Urea |
| What kind of medium is used for the Urease Test? | Urea broth |
| What are the ingredients in Urea broth? | 1. Urea 2. Phenol red |
| What is the inoculation/incubation method for the Urease test? | Loop inoculation |
| What is the chemical reaction when urea gets hydrolized? | Urea + H2O ---- Urease ----> CO2 + NH3 |
| What does NH3 do in the urease test? | It raises the pH |
| How is the urease test conducted after incubation? | Observe and look for color changes |
| What is the color produced when the urease test results are positive? | Phenol red turns PINKish/RED |
| What is the color produced when the urease test results are negative? | Yellow/Orange |
| What is the purpose of the Casein hydrolysis test? | Test to see if organism has casease enzyme that hydrolyzes casein |
| What kind of medium is used in the Casein hydrolysis test? | Skim milk agar |
| What is casein? | Milk protein |
| How is the casein hydrolysis test inoculated? | By putting a line in the middle of the agar |
| How is the casein hydrolysis test conducted after incubation? | Observe to see if there's a clear zone around line |
| How can you tell when a casein hydrolysis test is postive? | More clear looking area around line inoculation |
| What is the purpose of the starch hydrolysis test? | Test to see if organism has amylase enzyme to hydrolize Amylose |
| What is starch also known as? | Amylose |
| What kind of medium is used in the starch hydrolysis test? | Starch agar |
| How is the starch agar inoculated/incubated? | Draw a line in middle of agar |
| After incubation, how do you run the starch hydrolysis test? | Flood plate with IODINE to react with starch to produce blue/black color |
| How can you tell when a starch hydrolysis test is positive? | Clear zone around line |
| How can you tell when a starch hydrolysis test is negative? | No clear zone, line is blue/black as well |
| What is the purpose of the citrate test? | Test for citrate utilization as the sole carbon source |
| What kind of medium is used in the citrate test? | Simon's citrate agar slant |
| What are the ingredients of the citrate agar slant? | 1. sodium citrate 2. indicator - bromthymol blue |
| How is the medium inoculated in the citrate test? | Zig-zag inoculation on slant |
| How can you tell when the citrate test is positive? | the Green slant turns BLUE when organisms are growing |
| How can you tell when the citrate test is negative? | no color change |
| What is the purpose of the Kligler's iron agar test? | 1. glucose/lactose fermentation 2. gas production 3. hydrogen sulfide production |
| What family of bacteria is the Kligler's iron agar test mostly used on? | Enterobacteriaceae |
| What kind of medium is used in the Kligler's test? | Kligler's iron agar |
| What are the ingredients of the Kligler's iron agar? | 1. Glucose 0.1% 2. Lactose 1.0% 3. peptones 4. indicator: phenol red 5. H2S indicator: Ferrous sulfate |
| How is the Kligler's iron agar inoculated | Use needle inoculation, stabbing the butt, streaking the slant |
| How long should the Kligler's iron agar be incubated for? | 18-24 hours max |
| How can you tell when Hydrogen Sulfide (H2S) is produced? | Black precipitate (only occurs when fermentation occurs in acid condition) |
| T/F In the Kligler's iron agar test, glucose is less than lactose and is used first | True |
| If the results are positive in the KIA test and glucose is fermented, what color is the tube? | Tope of the tube is YELLOW |
| After glucose runs out, and lactose is used at the end of 18-24 hours, if fermentation occured, what color is the tube? | All Yellow = Glucose/lactose BOTH fermented |
| If organism uses up glucose, but doesn't ferment lactose, what happens? | Organism will use peptones causing REVERSION (tube turns RED again) ==> RED SLANT & YELLOW BUTT |
Created by:
lophung
Popular Biology sets