The pure culture of E. coli was inoculated in the Kligler iron agar. The possible results of E. coli growth are which of the following: 1. yellow slant 2. gas bubbles in the butt 3. yellow butt 4. black dots in the butt

Question

The pure culture of E. coli was inoculated in the Kligler iron agar. The possible results of E. coli growth are which of the following: 1. yellow slant 2. gas bubbles in the butt 3. yellow butt 4. black dots in the butt

Answer 1

The correct answer is 1, 2, and 4.Explanation:1. Yellow slant: E. coli ferments glucose and lactose, producing acid that lowers the pH of the medium. The yellow color indicates acid production.2. Gas bubbles in the butt: E. coli produces gas as a byproduct of fermentation.4. Black dots in the butt: E. coli reduces sulfur compounds, forming hydrogen sulfide (H2S), which reacts with iron salts to produceitates.Option 3 (yellow butt) is incorrect because E. coli does not ferment lactose to acid, so the butt should remain red.

Вопрос

The pure culture of E. coli was inoculated in the Kligler iron agar. The possible results of E. coli growth are which of the following: 1. yellow slant 2. gas bubbles in the butt 3. yellow butt 4. black dots in the butt

Решения

Ответ