Question

Which of these statements is/are true?

(i) The surface area available for cellular functions in a prokaryotic cell is less than that in a eukaryotic cell.
(ii) The total genome size of a prokaryotic cell is always less than that of a eukaryotic cell.
(iii) Unlike eukaryotes, no special respiratory organelles are found in prokaryotes. Hence they respire at a much less rate than eukaryotes.
(iv) Eukaryotic cells show various membrane-bound organelles such as chloroplasts and nucleus while ribosomes are the only membrane-bound organelles found in prokaryotes.

• A. (i) and (ii)
• B. (iv) only
• C. (iii) only
• D. (i), (ii) and (iv)

Answer 1

Answer: (A)

(i) and (ii)

The cellular and genomic organisation of prokaryotes are fundamentally different from that of eukaryotes.

• Prokaryotic cells have a small, simple structure compared to eukaryotic cells. They have less surface area per volume. Prokaryotes have simpler and smaller genomes than eukaryotes. In the majority of prokaryotes, the genome consists of a ring of DNA with few associated proteins.
• The eukaryotic genome is larger, organised into chromosomes, and is complexed with histone proteins.
• Unlike eukaryotes, prokaryotes do not have membrane-bound organelle for respiration but many enzymes needed for cellular respiration are attached to the plasma membrane, which may fold and extend into the cell. Ribosomes are the only cytoplasmic organelles in prokaryotes and they are not membrane-bound.

So, the correct answer is '(i) and (ii)'.