Question

after incubation in tryptone broth, what reagent is added to test for indole production?
iodine
hydrogen peroxide
methyl red
kovacs reagent
question 6 (1 point)
phenol red in the phenol red broth is a(n)_______________.
end product
carbohydrate
reagent
ph indicator

Explanation:

• For the first question: Kovac's reagent is used to test for indole production. It reacts with indole (if present) to form a red - colored complex. Iodine is used in tests like the starch - iodine test. Hydrogen peroxide is used in catalase tests. Methyl red is used in the methyl red test for pH changes related to mixed acid fermentation.
• For the second question: Phenol red in phenol red broth is a pH indicator. It changes color depending on the pH of the broth. An end product would be something like an acid or gas produced by bacterial metabolism. A carbohydrate is a nutrient source in the broth. A reagent is a general term for a chemical used in a test, but more specifically, phenol red's role is as a pH - sensitive color - changing substance.

Answer:

• First question: Kovac's reagent
• Second question: pH indicator