1. Which one of the following characteristics is NOT shown by a virus?
(A) They are acellular.
(B) They can be crystallised.
(C) Active outside the host’s body.
(D) Have genetic material.
Viruses are inert outside the host cell.
2. Select the WRONG statement.
(A) Pseudopodia are locomotory and feeding structures in Sporozoans.
(B) Mushrooms belong to Basidiomycetes.
(C) Cell wall is present in members of Fungi and Plantae.
(D) Mitochondria are the powerhouse of the cell in all kingdoms except Monera.
Pseudopodia are locomotory and feeding structures in Protozoans.
3. Which of the following are found in extreme saline conditions?
(A) Archaebacteria
(B) Eubacteria
(C) Cyanobacteria
(D) Mycobacteria
Bacteria found in extremely saline conditions are called halophiles. Archaebacteria includes bacteria that survive in most harsh habitats such as extreme salty area, hot springs and marshy area.
4. Viroids differ from viruses in having
(A) DNA molecules with protein coat
(B) DNA molecules without protein coat
(C) RNA molecules with protein coat
(D) RNA molecules without protein coat
Viroids are smaller than viruses. They are regarded as sub-viral agents or free RNA, without protein coat (usually found in viruses). They are infectious RNA. e.g. Potato spindle tuber disease.
