Question

In the three domain system, the domain Eukarya consists of all organisms that have which of the following?

Contractile vacuole
Nucleus
Chloroplast

Answer 1

I think the correct answer from the choices listed above is the second option. In the three domain system, the domain Eukarya consists a nucleus of all organisms. This is what is unique with this domain, a nucleus is present whereas the the others do not have one.

Answer 2

Answer: The correct answer is Nucleus.

Three domain system is the system of biological classification, which was given by Carl Woese in 1977. Life forms are divided into Archaea, Bacteria, and Eukarya.

Eukarya consists of those living organisms, which possess a membrane bound true nucleus ( unlike archaea and bacteria), which contains the genetic material of the organism.

Thus, nucleus is the right answer for the domain Eukarya.