Question

Which of the following is called as "Jokers of microbiological park"?
A. Bacteria
B. Mycoplasma
C. Nostoc
D. None of the above

Answer 1

Hint: Pleomorphic organisms are the ones which do have any definite shape and size. Therefore, they are known as “jokers of the microbiological park”. Their shape ranges from spherical to filamentous branched structure.

Complete step by step answer:
Mycoplasma are the pleomorphic microorganisms (in greek, “pleo” refers to many and “morph” refers to forms). The size of these microorganisms ranges in terms of diameter from 0.125 to 0.150 micrometer. These are the smallest known free living microorganisms. These organisms are capable of carrying out reproduction. Also, their cell walls do not contain murein or peptidoglycans therefore they can stretch and change their size and shape as per the environmental conditions. The mycoplasmas can inhabit as parasites on plants and have got the ability to pass through filters that are bacteria-proof.
Moreover, mycoplasma falls in the genus of bacteria only. They lack cell walls and are bounded by cell membranes. On the other hand filaments of nostoc comprises barrel-shaped or spherical cells. All these cells are of uniform size. Their color ranges from olive green to blue green. Also, the coiled, bent or kinked filaments of nostoc are isopolar and lengthy. These filaments are held to each other with the help of firm mucilage.
So, the correct answer is option “B” that is mycoplasma is called "Jokers of the microbiological park".

Note:
Lack of a cell wall in mycoplasma makes them resistant to various antibiotics. Therefore they are parasitic or saprophytic in nature thus harming the plants on which they live.