Which among the following are the smallest living cells, known without a definite cell wall, pathogenic to plants as well as animals and can survive without oxygen?
Answer: (C) Mycoplasma. Answer: (C) Mycoplasma Solution: Mycoplasmas are the smallest cells, only about 0.3 µm in length, and uniquely among prokaryotes they lack a cell wall (all prokaryotes have a cell wall surrounding the cell membrane except mycoplasma).
- A.Bacillus
- B.Pseudomonas
- C.Mycoplasma✓
- D.Nostoc
Correct Answer
(C) Mycoplasma
Solution & Explanation
Answer: (C) Mycoplasma Solution: Mycoplasmas are the smallest cells, only about 0.3 µm in length, and uniquely among prokaryotes they lack a cell wall (all prokaryotes have a cell wall surrounding the cell membrane except mycoplasma). They are pleuro-pneumonia-like organisms that are pathogenic and can survive anaerobically. Bacillus, Pseudomonas and Nostoc all possess cell walls. NCERT Reference: Ch 8, p.88, line 45: "Mycoplasmas, the smallest cells, are only 0.3 mm in length while bacteria"