Question

Which organism does not have a cell wall and is the smallest living cell?
A) Algae
B) Bacteriophage
C) Cyanobacteria
D) Mycoplasmas

Answer 1

Hint: Biological classification is the scientific classification of bacteria, fungi, protests, plants and animals. There are five –kingdom systems of classification.

Complete answer:
Kingdom Monera , Kingdom fungi,Kingdom protests, Kingdom plants and Kingdom animals come under the five-kingdom classification.
These five kingdoms further divided into sub groups or classification.
From the above five groups only kingdom monera have the organisms which do not have the cell walls and the smallest cell.
Kingdom monera is further divided into bacteria, actinomycetes, mycoplasma, cyanobacteria, and archaebacteria.
Bacteria are unicellular and they play an important role in decaying the organic waste material, sewage disposal, improving soil fertility and in industry for fomentation.
Actinomycetes are unicellular and also known as ray fungi. They are used in the medicine industry because various species of these produce antibiotics.
Mycoplasma are unicellular; they don’t have cell walls around their cellular system and they survive without the oxygen. They are the smallest living organisms.
Cyanobacteria are used to fix the environmental nitrogen.
Archaebacteria are living in extreme environments like hydrothermal vents.

So, the correct answer is Mycoplasma organism does not have a cell wall and is the smallest living cell.

Note:These organisms do not have the specific shape that is why they are called jokers of the plant kingdom.These organisms can be either parasitic or saprotrophic.