Video Transcript
Organisms belonging to kingdom
Fungi are eukaryotic. Which of the following best
explains what this means? (A) Their cells have the majority
of their genetic material contained in a plasmid. (B) Their cells have the majority
of their genetic material contained in a single chromosome loop. (C) Their cells have the majority
of their genetic material freely moving within the cytoplasm. (D) Their cells have the majority
of their genetic material contained in a membrane-bound nucleus.
We know from this question that
fungi are eukaryotic, but what does this mean? To explain this, let’s first
discuss the three domains of life: Eukarya, Archaea, and Bacteria.
The domain of Eukarya is defined as
having membrane-bound organelles, such as the nucleus, where the majority of their
DNA is stored as multiple linear chromosomes. Eukarya are, as the name suggests,
eukaryotic. Archaea and Bacteria are
prokaryotic, meaning they do not have membrane-bound organelles or nuclei. In general, prokaryotes have their
DNA exist as a single chromosome loop contained in the cytoplasm.
Now let’s look at these answer
choices again and eliminate the incorrect ones.
Answer choice (A) is incorrect
because the majority of genetic material in a eukaryote is contained within the
nucleus. Plasmids are generally found in
prokaryotic organisms and contain extrachromosomal DNA.
Answer choice (B) is also incorrect
because eukaryotes generally have their DNA exist as multiple linear chromosomes,
whereas prokaryotes generally have a single chromosomal loop.
Answer choice (C) is incorrect
because eukaryotes contain their DNA within a nucleus and not freely moving within
the cytoplasm. This is a characteristic of
prokaryotic DNA.
Answer choice (D) is correct
because eukaryotes contain their DNA within a nucleus.
Therefore, the term “eukaryotic” is
best explained by answer choice (D). Their cells have the majority of
their genetic material contained in a membrane-bound nucleus.
