(Study material) questions from micro-organisms and bacteria's morphology

Microorganisms include all unicellular organisms and so are extremely diverse.These were previously grouped together in the two domain system as Prokaryotic, the other being the Eukaryotas.The third domain Eukaryota includes all multi cellular organisms and many unicellular protagonists and protozoans.Some protagonists are related to animals and some to green plants.

Many of the multi cellular organisms are microscopic, namely micro-animals, some fungi and some algae,

The earliest known idea to indicate the possibility of diseases spreading by yet unseen organisms was that of the Roman scholar Marcus Pretentious Alvaro
in a 1st-century BC book titled On Agriculture
in which he called the unseen creatures animalcules,and warns against locating a homestead near a swamp
And because there are bred certain minute creatures that cannot be seen by the eyes,
which float in the air and enter the body through the mouth and nose and they cause serious diseases.
Of the three domains of life identified by Carl Worse, all of the Archean and Bacteria are microorganisms.

The basic forms are spheres (coccus) and round-ended cylinders (bacillus).
But there may be others such as helically twisted cylinders (spirochetes),
cylinders curved in one plane (Selenomonads) and unusual morphologies (such as the square Archaea Haloquadratum).
They also conform diplos, tetrads, staphylos, streptos, Palisades etc.