Question

Non-membrane bound cell organelles found in both prokaryotic and eukaryotic cells are:

• A. Mitochondria
• B. Lysosomes
• C. Centrosomes
• D. Ribosomes

Hint:

Logic Tip: Remember the "Universal Organelle". Every living cell must make proteins to survive, so every living cell must have the machinery to do so (Ribosomes). Because prokaryotes lack internal membranes, this universal machine must be non-membrane bound.

Answer 1

The Correct Option is D

Step 1 : Understanding the Question:
The question asks to identify a specific cell organelle that satisfies two criteria: it must not have a surrounding membrane and it must be present in both prokaryotes (like bacteria) and eukaryotes (like plant/animal cells).
Step 2 : Key Formulas and Approach:
1. Membrane-bound organelles (Mitochondria, Plastids, ER, Golgi, Lysosomes) are exclusive to eukaryotes.
2. Non-membrane bound organelles include Ribosomes, Centrioles, and Nucleoli.
3. We must find the one that is universal to all life forms.
Step 3 : Detailed Explanation:

Mitochondria (A): These are double-membrane bound organelles responsible for ATP production. They are found only in eukaryotic cells. Incorrect.

Lysosomes (B): These are single-membrane bound vesicles containing hydrolytic enzymes. They are found only in eukaryotic cells. Incorrect.

Centrosomes (C): These are non-membrane bound, but they are primarily found in animal cells (eukaryotes) to aid in cell division. They are absent in prokaryotes. Incorrect.

Ribosomes (D): Ribosomes are dense, granular particles composed of ribosomal RNA and proteins. They lack any membrane. Most importantly, they are the site of protein synthesis and are present in all living cells, including prokaryotes (70S) and eukaryotes (80S and 70S).

Step 4 : Final Answer:
Ribosomes are the only organelles that are both non-membrane bound and common to every cell type. This leads to option (D).