Practice MCQ Questions and answers on Biology-GK

A virus is an infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. They range in size from about 20 to 300 nanometres in diameter.

Two scientists contributed to the discovery of the first virus, Tobacco mosaic virus. Ivanoski reported in 1892 that extracts from infected leaves were still infectious after filtration through a Chamberland filter-candle.

The correct answer is Microbiology.

Microbiology is the branch of science that deals with the study of microorganisms. Microorganisms are very, very small living things that you can't see with your bare eyes, like bacteria, viruses, fungi, and protozoa. You need a microscope to see them! Microbiologists study how these tiny creatures live, where they live, what they do, and how they affect us (both good and bad).

Now let's quickly look at why the other options are not correct:

Option A: Evolution is the study of how different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the Earth. It's about changes over a very long time, not specifically about microorganisms.

Option C: Zoology is the scientific study of animals. This includes everything from insects to elephants, but not the tiny, microscopic organisms.

Option D: Palaeontology is the scientific study of life that existed in prehistoric times through the examination of fossils. It focuses on ancient life forms, usually much larger than microorganisms, and is based on their preserved remains (fossils).

So, when you hear 'microorganisms', think 'Microbiology'!

Entamoeba histolytica is a protozoan parasite that accounts for an estimated 100,000 annual deaths globally.

Amoeba belongs to which group protozoa.

Late blight is caused by the oomycete Phytophthora infestans. Oomycetes are fungus-like organisms also called water molds, but they are not true fungi.

The earliest record of an amoeboid organism was produced in 1755 by August Johann Rösel von Rosenhof, who named his discovery "Der Kleine Proteus" ("the Little Proteus").

Rhizopus stolonifer is commonly known as black bread mold. It is a member of Zygomycota and considered the most important species in the genus Rhizopus.

In N₂ - fixation process, nitrite is converted to nitrate by nitrobacter.

Green mould is common name for Penicillium digitatum.