Membrane-bound organelles are absent in
(1) Saccharomyces
(2) Streptococcus
(3) Chlamydomonas
(4) Plasmodium
Concept Questions :-
Difficulty Level:
Virus envelope is known as
(1) capsid
(2) virion
(3) nucleoprotein
(4) core
Concept Questions :-
Difficulty Level:
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
Concept Questions :-
Difficulty Level:
Infectious proteins are present in
(1) gemini viruses
(2) prions
(3) viroids
(4) satellite viruses
Concept Questions :-
Difficulty Level:
Oxygenic photosynthesis occurs in
(1) Chromatium
(2) Oscillatoria
(3) Rhodospirillum
(4) Chlorobium
Concept Questions :-
Difficulty Level:
T. O. Diener discovered a
(1) free infectious RNA
(2) free infectious DNA
(3) infectious protein
(4) bacteriophage
Concept Questions :-
Difficulty Level:
Consider the following four measures (A-D) that could be taken to successfully grow chick pea in an area where bacterial blight disease is common
(A) spray with Bordeaux mixture
(B) control of the insect vector of the disease pathogen
(C) use of only disease-free seeds
(D) use of varieties resistant to the disease
Which two of the above measures can control the disease?
(1) B and C
(2) A and B
(3) C and D
(4) B and D
Difficulty Level:
Bacterial leaf blight of rice is caused by a species of
(1) Xanthomonas
(2) Pseudomonas
(3) Alternaria
(4) Erwinia
Difficulty Level:
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
Concept Questions :-
Difficulty Level:
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
Concept Questions :-
Difficulty Level: