Question

which structure can be found in both eukaryotic and prokaryotic cells?
a mitochondrion
b nucleus
c chloroplast
d nucleic acid

Explanation:

• Mitochondrion: Prokaryotic cells lack mitochondria. Mitochondria are membrane - bound organelles found in eukaryotic cells (e.g., animal and plant cells) and are responsible for energy production (ATP synthesis) through cellular respiration.
• Nucleus: Prokaryotic cells do not have a true nucleus. In prokaryotes, the genetic material (DNA) is in the nucleoid region (not enclosed by a nuclear membrane), while in eukaryotes, the DNA is enclosed within a double - membrane - bound nucleus.
• Chloroplast: Chloroplasts are membrane - bound organelles found in some eukaryotic cells (such as plant cells) and are involved in photosynthesis. Prokaryotic cells do not have chloroplasts. Some prokaryotes (like cyanobacteria) can perform photosynthesis but use different structures (thylakoid - like membranes in the cytoplasm).
• Nucleic acid: Both prokaryotic and eukaryotic cells contain nucleic acids. Prokaryotes have DNA (usually in a circular form in the nucleoid) and RNA (for processes like transcription and translation). Eukaryotes have DNA (in the nucleus, mitochondria, and chloroplasts in plants) and RNA (in the nucleus, cytoplasm, etc.) which are involved in storing (DNA) and expressing (both DNA and RNA) genetic information.

Answer:

D. Nucleic acid