Subject Experts Solutions for Exercise 1: MCQS CORNER

Which one of the following is an incorrect pair?

In plants, mosaic formation, leaf rolling and curling, yellowing of plant parts, vein clearing, dwarfing and stunted growth, necrosis etc. are the symptoms of

Which of the following is not a viral disease of plants?

Read the given statements that describe certain infectious particles.
(i) It was discovered by T.O. Diener and was found to be smaller than viruses.
(ii) It causes potato spindle tuber disease.
(iii) It is a free RNA particle that lacks the protein coat.
(iv) It has low molecular weight RNA as genetic material.
Which of the following is referred to here?

Read the given statements about lichens and select the incorrect ones.
(i) They represent an example of commensalism.
(ii) Algal partner obtains water and mineral salts from the fungus and the fungal partner obtains food prepared by the alga.
(iii) These do not grow in polluted areas.
(iv) The mycobiont is usually an Ascomycetes or a Basidiomycetes.
(v) The phycobiont is mostly a green alga or a cyanobacterium.
(vi) These constitute the pioneer community in case of hydrosere.

Choose the incorrect statement.

Match column I with column II and select the correct option from the given codes.

Read the following statements and select the option which identifies the incorrect ones.
(i) Potato spindle tuber disease and Chrysanthemum stunt disease are caused by viroids.
(ii) ${\mathrm{T}}_4$ bacteriophage exhibits lytic cycle.
(iii) Retroviruses have two copies of ssRNA.
(iv) Interferons which prevent viral multiplication are glycolipid particles.