While examining a rock surface, you have discovered an interesting new organism. Which of the

following criteria will allow you to classify the organism as belonging to Bacteria but not Archaea

or Eukarya?

A) It is unicellular.

B) Cell walls are made primarily of peptidoglycan.

C) The lipids in its plasma membrane consist of glycerol bonded to straight-chain fatty acids.

D) It can survive at a temperature over 100°C.

E) Organism does not have nucleus.

B) Cell walls are made primarily of peptidoglycan.

Explanation:

The presence of peptidoglycan in the cell walls of the organism is enough to classify the organism as belonging ot bacteria.

A is incorrect because being unicellular is not exclusive to bacteria only. Members of Archaea and some members of Eukarya are also unicellular.

C is not correct because because the component of the plasma membrane is similar in the three classes of organisms.

D is not correct because only members of Archaea have the ability to survive in extreme environments such as very high temperature.

E is incorrect because both bacteria and archaea lack nucleus.

The correct option is B.

option B

Explanation:

The bacteria cell walls is made up of mainly peptidoglycans. Archae is made up e. g pseudo-peptidogycans and others instead of peptidoglycans and eukarya are made up of many more substances other than peptidoglycans. Archae are also unicellular. Some groups of archae can survive at this temperature too. Thus what differentiates this organism from eukarya and archae is that its cell wall is made primarily of peptidoglycans.