Question

The dichotomous key illustrated here allows the classification of microorganisms based on their metabolic characteristics. Suppose some organisms ferment lactose but can't use citric acid for all their carbon needs. These organisms must be

Answer 1

The answer is C) Escherichia. When you follow the path down it shows it. Plus,I just answered the question and I got it right

Answer 2

The organism must be Escherichia coli

Escherichia coli is a bacterium of the family Enterobacteriaceae.

Escherichia coli is abundant in the commensal flora, particularly in the digestive tract.

Aerobic bacillus, Gram negative, oxidase negative, nitrate positive and which ferments glucose.

* fermentation of sugars: glucose +, lactose +

* reduction of nitrates to nitrites: NO3 +

* metabolism of tryptophan to indole: ind +