Question

a defining characteristic of eukaryotic organisms is that
multiple choice
transcription occurs in the nucleus and translation in the cytoplasm.
only have operons to assist in gene expression.
they use the leucine zipper primarily for the production of the amino acid tryptophan.
transcription occurs in the cytoplasm and translation in the nucleus.
they carry out protein synthesis only in the presence of the camp molecule.

Explanation:

Eukaryotic organisms have a nucleus. Transcription (DNA - to - RNA conversion) occurs in the nucleus where DNA is located, and translation (RNA - to - protein conversion) occurs in the cytoplasm at ribosomes. Operons are mainly found in prokaryotes, leucine zippers have multiple functions not mainly for tryptophan production, and the correct locations for transcription and translation in eukaryotes are nucleus and cytoplasm respectively, not the other way around. Also, protein synthesis in eukaryotes is not solely dependent on cAMP.

Answer:

transcription occurs in the nucleus and translation in the cytoplasm.