Biological Classification Test - 4

Prions are abnormally folded proteins which are made of amino acids.

Nucleic acids are used in the reproduction of DNA and play a role in protein synthesis, but they are not directly embedded into the protein.

Therefore, prions do not contain any nucleic acid (or genetic information) within them.

Mycology is the branch of biology which deals with the study of fungi, including their properties, taxonomy and whether they are useful or harmful.

Plant virus such as cauliflower mosaic virus causes plant diseases. The symptoms include mosaic formation, leaf rolling and curling, yellowing of plant parts, vein clearing, dwarfing and stunted growth. 

Unicellular eukaryotes (except some unicellular algae and fungi) are grouped under kingdom Protista. Protists are considered as the phylogenetic link between kingdom Monera and multicellular eukaryotic organisms.

Monerans are prokaryotic organisms. Prokaryotic cells do not have membrane-bound organelles and a distinct nucleus bound by the nuclear membrane.

Lichens do not grow in polluted air. Hence, the regions where there is minimal growth of lichens despite the suitable condition for their growth may indicate increased pollution in that region.

Bacteria belong to kingdom Monera, and it is a prokaryote. A prokaryote does not have membrane-bound cell organelles.

M. W. Beijerinck demonstrated that the extract of infected tobacco plant can infect the healthy plant. He named this extract as Contagium vivum fluidum.

Rust, smut and mushroom belong to phylum basidiomycetes of kingdom Fungi. Basidiomycetes decompose the woody structure of trees. They decompose cellulose and lignin. Rusts are parasitic on certain species of wheat and coffee. Smuts infect corn, wheat etc., and mushrooms are parasitic on the bark and roots of certain trees.

Lichens are a symbiotic association between fungi and algae. The fungal component is heterotrophic and known as mycobiont, while the algal component is autotrophic and known as phycobiont.