Same chapter3 marksDifficulty: Medium
Why are mitochondria and chloroplasts called semi-autonomous organelles?
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3 marksDifficulty: Medium
What are ribosomes made of, and what is the difference between 70S and 80S ribosomes?
Original Khojo Papers practice question — not from a past board paper.
Answer
Ribosomes are made of ribosomal RNA and proteins, and they have no membrane. The 70S ribosome, of 50S and 30S subunits, is found in prokaryotes and in mitochondria and chloroplasts. The 80S ribosome, of 60S and 40S subunits, is found in the cytoplasm of eukaryotes.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
S refers to the sedimentation coefficient, which is why the subunit values do not add arithmetically.
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