Correct Option
The correct option is (c) 1 and 3 only.
Explanation
Ribosomes are granular structures found within the cytoplasm of cells. They are composed of ribonucleic acid (RNA) and proteins and are the primary machinery for protein synthesis.
Statement-wise Analysis
- Statement 1 is Correct: Ribosomes are non-membrane-bound organelles. Unlike organelles such as the nucleus, mitochondria, or lysosomes, ribosomes lack a surrounding lipid membrane.
- Statement 2 is Incorrect: Ribosomes are present in both prokaryotic and eukaryotic cells. While their structure varies slightly (70S in prokaryotes and 80S in eukaryotes), they are a universal feature of all living cells.
- Statement 3 is Correct: Ribosomes are the sites of protein manufacture. They translate genetic information carried by messenger RNA (mRNA) into polypeptide chains to form proteins.
Key Takeaway: Ribosomes are the "protein factories" of the cell; they are non-membrane-bound organelles found in both prokaryotic and eukaryotic organisms.