Question

The outermost limiting layer of Mycoplasma is made up of
A) Cell wall
B) Cell membrane
C) Mucilaginous sheath
D) Slime layer

Answer 1

Hint: Mycoplasma or PPLO (Pleomorphic pneumonia like organisms) have no cell walls which makes them get into many shapes.

Complete Answer:
- Mycoplasma is a genus of the kingdom Monera which lacks a cell wall. They have the outermost layer made up of cell membrane. So, their cells lack a specific shape.
- Plants and cyanobacteria show the presence of a mucilaginous sheath that is made up of a thick and gluey substance called mucilage. Slime layer is a glycoprotein layer which is loosely associated and is present outside the cell wall.

Thus, the correct answer is option (B) Cell membrane.

Additional information:
Mycoplasma is a genus of the smallest bacteria. Its outer limiting layer is formed of cell membrane. They do not have a cell wall around the cell membrane. In the absence of a cell wall, they are found to be resistant to many antibiotics like penicillin.

Note: Mycoplasma is the simplest and smallest free-living Gram-negative monerans or prokaryotes. Cell wall is absent in them. The plasma membrane has a trilipid layer forming the outer boundary of the cell. There is a high amount of polysaccharides (acetyl glucosamine ) associated with the cell membrane.