1. The dye eosinate of methylene blue belongs to which group?a) Acidic dyeb) Basic dyec) Neutral dyed) Oxazine dye

2. What is the correct order of staining reagents in Gram-Staining?

a) Crystal violet, alcohol, iodine solution, safranin

b) Crystal violet, iodine solution, alcohol, safranin

c) Crystal violet, safranin, alcohol, iodine solution

d) Iodine solution, crystal violet, alcohol, safranin

3. Which bacteria appears purple-violet colour after staining?

a) Gram-positive

b) Gram-negative

c) Both Gram-positive and Gram-negative

d) Neither Gram-positive nor Gram-negative

4. Which of the following are true for Gram-negative bacteria?

a) upon alcohol treatment, the permeability of the cell wall increases

b) crystal violet-iodine (CV-I) complex is extracted

c) pore size decreases and the CV-I complex cannot be extracted

d) alcohol treatment increases the permeability of the cell wall and the CV-I complex can be extracted

5. Gram-positive bacteria are usually more susceptible to?

a) streptomycin

b) tetracyclin

c) penicillin

d) ampicillin

6. Which of the staining technique helps in demonstrating spore structure in bacteria as well as free spores?

a) Acid-fast stain

b) Endospore stain

c) Capsule stain

d) Flagella stain

7. In Gram-staining, iodine is used as a ______________

a) fixative

b) mordant

c) solublizer

d) stain

8. Which of the following is the example of Gram-negative bacteria?

a) Lactobacillus

b) Eschericia coli

c) Staphylococcus aureus

d) Bacillus subtilis