Single-celled eukaryotes are included in
(1) Protista
(2) Fungi
(3) Archaea
(4) Monera
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Membrane-bound organelles are absent in
(1) Saccharomyces
(2) Streptococcus
(3) Chlamydomonas
(4) Plasmodium
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Virus envelope is known as
(1) capsid
(2) virion
(3) nucleoprotein
(4) core
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Some hyperthermophilic organisms that grow in highly acidic (pH2) habitats belong to the two groups called
(1) eubacteria and archaea
(2) cyanobacteria and diatoms
(3) protists and mosses
(4) liverworts and yeasts
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Infectious proteins are present in
(1) gemini viruses
(2) prions
(3) viroids
(4) satellite viruses
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Oxygenic photosynthesis occurs in
(1) Chromatium
(2) Oscillatoria
(3) Rhodospirillum
(4) Chlorobium
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T. O. Diener discovered a
(1) free infectious RNA
(2) free infectious DNA
(3) infectious protein
(4) bacteriophage
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Bacterial leaf blight of rice is caused by a species of
(1) Xanthomonas
(2) Pseudomonas
(3) Alternaria
(4) Erwinia
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In the light of recent classification of living organisms into three domains of life (bacteria, archaea and eukarya), which one of the following statement is true about archaea?
(1) Archaea resemble eukarya in all respects
(2) Archaea have some novel features that are absent in other prokaryotes and eukaryotes
(3) Archaea completely differ from both prokaryotes and eukaryotes
(4) Archaea completely differ from prokaryotes
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Thermococcus, Methanococcus and Methanobacterium exemplify
(1) archaebacteria that contain protein homologous to eukarytic core histones
(2) archaebacteria that lack any histones resembling those found in eukaryotes but whose DNA is negatively supercoiled
(3) bacteria whose DNA is relaxed or positively supercoiled but which have a cytoskeleton as well as mitochondria
(4) bacteria that contain a cytoskeleton and ribosomes
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