Advanced Laboratory Techniques in Biology, Chemistry, and Physics

1. What plate is this? What does it test for? What is a positive result?

Milk PlatecaseinaseClearing

Agar Plate - Amylase - Blue Color

Sugar Plate - Cellulase - Swarming

Blood Agar Plate - Lipase - Hemolysis

The correct answer refers to a Milk Plate testing for Caseinase activity resulting in clearing of the plate.

Explanation

The correct answer refers to a Milk Plate testing for Caseinase activity resulting in clearing of the plate.

2. What is the result of a Citrate test? What does it test for and what is the media used?

Negative for Citrate utilization Citrate as sole carbon sourceSimmon's Citrate Slant

Negative for Citrate utilization. Utilization of Sucrose. MacConkey Agar.

Positive for Citrate utilization. Utilization of lactose. Eosin Methylene Blue Agar.

Positive for Citrate utilization. Citrate as glucose source. OF Glucose medium.

The Citrate test is used to determine if an organism can utilize Citrate as a sole carbon source. Negative result implies the organism cannot use Citrate. Simmons Citrate Slant is the specialized media used for this test.

Explanation

The Citrate test is used to determine if an organism can utilize Citrate as a sole carbon source. Negative result implies the organism cannot use Citrate. Simmons Citrate Slant is the specialized media used for this test.

3. What are the results for this pigment test? Name the organism we used and the specific media we used for it.

Intracellular pigment productionM. roseus on NA slant

Extracellular pigment production, E. coli on LB agar

Intracellular pigment production, P. aeruginosa on MacConkey agar

No pigment production, S. aureus on Blood agar

The correct answer describes the results of the pigment test with M. roseus on NA slant. The incorrect answers provide different scenarios with other organisms and media that do not match the given question.

Explanation

The correct answer describes the results of the pigment test with M. roseus on NA slant. The incorrect answers provide different scenarios with other organisms and media that do not match the given question.

4. What test is this? What does it test for? What is the result of this particular tube?

Protein digestion test Tests for breakdown of proteins Positive for protein digestion, Alkaline only.

Nucleic acid synthesis test Tests for synthesis of nucleic acids Positive for nucleic acid synthesis, Alkaline and Acid.

Carbohydrate fermentation testTests for fermentation of sugarsPositive for sugar fermentation, Acid only

Lipid oxidation test Tests for oxidation of lipids Positive for lipid oxidation, Neutral.

The correct answer describes the Carbohydrate fermentation test, which tests for fermentation of sugars and results in acid production. The incorrect answers provide alternative tests with different purposes and results to confuse the test taker.

Explanation

The correct answer describes the Carbohydrate fermentation test, which tests for fermentation of sugars and results in acid production. The incorrect answers provide alternative tests with different purposes and results to confuse the test taker.

5. What is this plate? What does it test? Is it differential or selective? What is the pH indicator in this test? What can we say about organism SA? SP? EC?

MAC plate; Gram Staining; Both; Litmus Red; SA Gram Positive, SP Gram Negative, EC Gram Positive

EMB plate; Lactose Fermentation; Selective; Methyl Red; SA Lactose + Mannitol Fermentation, SP Lactose - Mannitol Fermentation, EC Lactose Negative

BAP plate; Hemolysis and Coagulase Production; Differential; Bromothymol Blue; SA Hemolysis + Coagulase, SP Hemolysis - Coagulase, EC Coagulase Positive

MSA plateHalophile and Mannitol FermBothPhenol RedSA Halophile + Mann. FermSP Halophile - Mann FermEC Not a Halophile

6. What enzyme is tested for in a Lys Test? Is this tube positive or negative for the enzyme?

Lysine Decarboxylase Negative for enzyme

Tryptophan Deaminase, Positive for enzyme.

Arginine Deaminase, Positive for enzyme.

Ornithine Decarboxylase, Negative for enzyme.

The Lys Test specifically tests for Lysine Decarboxylase enzyme. A negative result indicates the absence of this enzyme in the test tube.

Explanation

The Lys Test specifically tests for Lysine Decarboxylase enzyme. A negative result indicates the absence of this enzyme in the test tube.

7. What does a positive citrate test indicate?

Positive for bacterial growth

Positive for protein degradation

Positive for carbohydrate fermentation

Positive for citrate utilization

In the citrate test, a positive result indicates that the bacterium is able to utilize citrate as its sole carbon source, leading to alkaline byproducts and a change in pH of the medium.

Explanation

In the citrate test, a positive result indicates that the bacterium is able to utilize citrate as its sole carbon source, leading to alkaline byproducts and a change in pH of the medium.

8. Barritt's reagent A is used in which test? When this reagent is added to its appropriate test, it gives a red color. Is that positive or negative?

VPPositive for non acidic fermentation (acetoin production)

Indole test. Negative for tryptophan metabolism.

Citrate test. Positive for citrate utilization.

Methyl Red test. Positive for mixed acid fermentation.

Barritt's reagent A is specifically used in the Voges-Proskauer test to detect the presence of acetoin, which results in a red color in the test tube. Therefore, a red color in this test indicates a positive result for non acidic fermentation.

Explanation

Barritt's reagent A is specifically used in the Voges-Proskauer test to detect the presence of acetoin, which results in a red color in the test tube. Therefore, a red color in this test indicates a positive result for non acidic fermentation.

9. Name the respective tests for these reagents. Tell me what those tests are used for.

Simmons citrate test, Benedict's test, Nitrate reduction test

MR test, Starch testMixed acid ferm. Caseinase

Catalase test, Biuret test, Lipase test

Voges-Proskauer test, Iodine test, Urease test

The question is asking for the tests associated with specific reagents and their respective uses. The correct answer provides the tests MR test, Starch testMixed acid ferm. Caseinase. The incorrect answers were chosen to provide a variety of different tests and differentiate them from the correct answer. This multiple-choice question aims to test knowledge of laboratory tests and reagents.

Explanation

The question is asking for the tests associated with specific reagents and their respective uses. The correct answer provides the tests MR test, Starch testMixed acid ferm. Caseinase. The incorrect answers were chosen to provide a variety of different tests and differentiate them from the correct answer. This multiple-choice question aims to test knowledge of laboratory tests and reagents.

10. What are the results of the tubes on the left and right in the given scenario?

-, Alk prod.- NH3 prod. on left, increase in pHno fermentation occurred on right

+, Alk prod.- NH3 prod. on left, no change in pHno fermentation occurred on right

-, Alk prod.- NH3 prod. on left, increase in pHfermentation occurred on right

-, Alk prod.- NH3 prod. on left, decrease in pHfermentation occurred on right

The correct answer indicates a specific set of results observed in the tubes on the left and right side. The incorrect answers either suggest variations in pH or presence of fermentation, which are not consistent with the original scenario described in the question.

Explanation

The correct answer indicates a specific set of results observed in the tubes on the left and right side. The incorrect answers either suggest variations in pH or presence of fermentation, which are not consistent with the original scenario described in the question.

11. Which test is used to test for catalase?

Amylase

Protease

Lipase

Catalase

The correct answer is Catalase, as it is a common test used to detect the presence of the enzyme catalase in biological samples.

Explanation

The correct answer is Catalase, as it is a common test used to detect the presence of the enzyme catalase in biological samples.

12. Describe the result of this test.

Positive for carb. ferm. acid and gas production

Neutral result with no significant findings.

Positive for carb. ferm. acid production, but negative for gas production.

Negative for carb. ferm. acid production, but positive for gas production.

The correct answer indicates a positive result for carbohydrate fermentation with acid and gas production, which are commonly used indicators for certain tests. The incorrect answers provide different scenarios that do not align with the expected outcome of the test.

Explanation

The correct answer indicates a positive result for carbohydrate fermentation with acid and gas production, which are commonly used indicators for certain tests. The incorrect answers provide different scenarios that do not align with the expected outcome of the test.

13. What test is this? What is the media used? What is the result?

H2S testPeptone iron deepPositive for cystein desulfurase

Urease test, Blood agar, Positive for starch hydrolysis.

Methyl Red test, Simmons Citrate media, Positive for indole production.

Catalase test, MacConkey agar, Negative for catalase enzyme.

The correct answer discusses the H2S test using Peptone iron deep media and the positive result for cystein desulfurase. The incorrect answers provide different tests, media, and results, showcasing the importance of understanding specific test procedures.

Explanation

The correct answer discusses the H2S test using Peptone iron deep media and the positive result for cystein desulfurase. The incorrect answers provide different tests, media, and results, showcasing the importance of understanding specific test procedures.

14. What do line A and line B represent in the context of the experiment?

A = susceptible colonies, B = no growth observed

A = killing dose of streptomycinB = highly resistant colonies

A = control group, B = test group

A = growth rate of bacteria, B = antibiotic concentration

In the provided question and correct answer, line A represents the killing dose of streptomycin and line B represents highly resistant colonies based on the experiment being referenced.

Explanation

In the provided question and correct answer, line A represents the killing dose of streptomycin and line B represents highly resistant colonies based on the experiment being referenced.

15. What is the result for this test?

- arginine decarboxylase

# threonine decarboxylase

* ornithine decarboxylase

+ lys decarboxylase

The correct result for this test is positive for lysine decarboxylase, which is indicated by the + sign. Arginine decarboxylase, ornithine decarboxylase, and threonine decarboxylase are not the correct results and therefore considered incorrect answers.

Explanation

The correct result for this test is positive for lysine decarboxylase, which is indicated by the + sign. Arginine decarboxylase, ornithine decarboxylase, and threonine decarboxylase are not the correct results and therefore considered incorrect answers.

16. When do we use Phe test and what color does it produce in a positive reaction?

Phe test, testing for phe aminase, green

Phe test, testing for protein levels, red.

Phe test, testing for glucose levels, blue.

Phe test, testing for vitamin C levels, yellow.

The Phe test is specifically used to test for the presence of phe aminase, and in a positive reaction, it produces a green color.

Explanation

The Phe test is specifically used to test for the presence of phe aminase, and in a positive reaction, it produces a green color.

17. What test is performed using urea slant as the media? What does this test determine? What is the result of this test?

Indole test, Simmons citrate agar, Motility

Urease testUrea slantUrease + for urease

Catalase test, Lysine iron agar, Hydrolysis

Oxidase test, Methyl red broth, Acid production

The urease test is conducted using urea slant as the media to detect the presence of urease enzyme and the ability of bacteria to hydrolyze urea. A positive result for this test indicates the bacteria's ability to produce urease.

Explanation

The urease test is conducted using urea slant as the media to detect the presence of urease enzyme and the ability of bacteria to hydrolyze urea. A positive result for this test indicates the bacteria's ability to produce urease.

18. IMViC test, respective order. Analyze results. What is the reagent for Indole? What does Indole test?

A. MR = + for mixed acid ferm. Reagent: Methyl red. Tests for mixed acid fermentation.

B. VP = - for Non acidic ferm. Reagent: Voges-Proskauer reagent. Tests for non-acidic fermentation.

C. Citrate = - for citrate utilization. Reagent: Simmons citrate agar. Tests for citrate utilization.

IMViC test is a set of four biochemical tests used for the differentiation of Enterobacteriaceae based on their ability to ferment glucose (Glucose Fermentation), produce methyl red (MR), produce acetoin (Voges-Proskauer, VP), and utilize citrate as the sole carbon source. Indole test is used to determine the presence of tryptophanase enzyme in bacteria, where Kovac's reagent is used to detect the formation of indole.

Explanation

IMViC test is a set of four biochemical tests used for the differentiation of Enterobacteriaceae based on their ability to ferment glucose (Glucose Fermentation), produce methyl red (MR), produce acetoin (Voges-Proskauer, VP), and utilize citrate as the sole carbon source. Indole test is used to determine the presence of tryptophanase enzyme in bacteria, where Kovac's reagent is used to detect the formation of indole.

19. What plate is this? What does it test? What is the result?

MacConkey Plate; Tests for coliforms; Red colonies are positive, no growth is negative

Blood Agar Plate; Tests for hemolytic activity of bacteria; Clear zones around colonies indicate beta hemolysis

Mannitol Salt Agar Plate; Tests for mannitol fermentation; Yellow colonies show positive fermentation, pink/red colonies indicate negative fermentation

The correct plate is EMB Plate which tests for G- or G+ organisms. The growth characteristics and color changes on the plate determine the result of the test.

Explanation

The correct plate is EMB Plate which tests for G- or G+ organisms. The growth characteristics and color changes on the plate determine the result of the test.

20. What does a PEA plate test for? Selective or differential?

Both Gram-positive and Gram-negative bacteria

G+ or G-Selective

Only Gram-negative bacteria

Only Gram-positive bacteria

A PEA (Phenylethyl Alcohol) plate is selective for Gram-positive bacteria due to the phenylethyl alcohol inhibiting the growth of Gram-negative bacteria.

Explanation

A PEA (Phenylethyl Alcohol) plate is selective for Gram-positive bacteria due to the phenylethyl alcohol inhibiting the growth of Gram-negative bacteria.

21. What is the purpose of the Gelatin test?

Test for motility. A result of + indicates presence of motility.

Test for urease production. A result of + indicates urease production.

Gelatin testTest for gelatinaseA is + for gelatinase

Test for starch hydrolysis. A result of + indicates complete hydrolysis of starch.

Test for lactose fermentation. A result of + indicates positive lactose fermentation.

The Gelatin test is to determine the presence of gelatinase enzymes. A positive result indicates the ability of the microorganism to hydrolyze gelatin.

Explanation

The Gelatin test is to determine the presence of gelatinase enzymes. A positive result indicates the ability of the microorganism to hydrolyze gelatin.

22. What are some methods for testing motility?

Agglutination testing

Blood agar plate streaking

Acid-fast staining

Soft agar stab inoculation and hanging drop technique

Testing motility involves assessing the ability of microorganisms to move. Soft agar stab inoculation and hanging drop technique are common methods used to determine motility in bacteria. Blood agar plate streaking, agglutination testing, and acid-fast staining are not specific methods for testing motility.

Explanation

Testing motility involves assessing the ability of microorganisms to move. Soft agar stab inoculation and hanging drop technique are common methods used to determine motility in bacteria. Blood agar plate streaking, agglutination testing, and acid-fast staining are not specific methods for testing motility.

23. What are the components of the FTB tube and what are FTB tubes used for?

Water, sugar, and salt; FTB tubes are used for measuring pH levels

Alcohol, hydrogen peroxide, and iodine; FTB tubes are used for testing blood glucose levels

Oil, vinegar, and baking soda; FTB tubes are used for analyzing soil composition

24. What are the characteristics of enterobacteriaceae?

B - Spirochetes, oxidase negative, produce acid in lactose fermentation.

C - Vibrios, oxidase positive, produce gas in glucose fermentation.

A - Cocci, oxidase positive, produce gas in lactose fermentation.

G - Bacillus, oxidase negative, produce acid in glu fermentation

Enterobacteriaceae are typically Bacillus-shaped, oxidase negative bacteria that produce acid in glucose fermentation. Other characteristics mentioned in the incorrect answers do not match the typical characteristics of this bacterial family.

Explanation

Enterobacteriaceae are typically Bacillus-shaped, oxidase negative bacteria that produce acid in glucose fermentation. Other characteristics mentioned in the incorrect answers do not match the typical characteristics of this bacterial family.