Question

Which of the following are characteristics of prokaryotic cells? (a) Ribosomes are made of 50S and 30S subunits (b) They can have plasmids (c) They contain mesosome (d) They have peroxisomes Choose the correct answer from the options given below :

• A. (a), (b) and (c) only
• B. (b) and (c) only
• C. (a) and (c) only
• D. (a), (c) and (d) only

Hint:

Remember the key features of prokaryotes:

• 70S ribosomes (50S + 30S)

• Plasmids may be present

• Mesosomes present

• No membrane-bound organelles

• No mitochondria, ER, Golgi bodies or peroxisomes

Answer 1

The Correct Option is A

Step 1: Understand the task.
We must decide which of statements (a) to (d) are true for prokaryotic cells.
Step 2: Check statement (a).
Prokaryotic ribosomes are $70S$, made of a $50S$ large subunit and a $30S$ small subunit, so statement (a) is correct.
Step 3: Check statement (b).
Prokaryotes can carry plasmids, small circular DNA pieces that replicate on their own, so statement (b) is correct.
Step 4: Check statement (c).
Mesosomes are infoldings of the plasma membrane found in prokaryotes that help in cell wall formation and DNA distribution, so statement (c) is correct.
Step 5: Check statement (d).
Peroxisomes are membrane-bound organelles found only in eukaryotes, so prokaryotes do not have them and statement (d) is incorrect.
Step 6: Combine and conclude.
Statements (a), (b), and (c) are correct while (d) is wrong, so the right option is (a), (b) and (c) only.
\[ \boxed{(a),\ (b)\ \text{and}\ (c)\ \text{only}} \]