Bacterial leaf blight of rice is caused by a species of
(1) Xanthomonas
(2) Pseudomonas
(3) Alternaria
(4) Erwinia
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
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
Which of the following is a flowering plant with nodules containing filamentous nitrogen-fixing microorganism?
(1) Casuarina equisetifolia
(2) Crotolaria juncea
(3) Cycas revoluta
(4) Cicer arietinum
Which of the following is a slime mould?
(1) Rhizopus
(2) Physarum
(3) Thiobacillus
(4) Anabaena
A genetically engineered micro-organism used successfully in bioremediation of oil spills is a species of:
(1) Pseudomonas
(2) Trichoderma
(3) Xanthomonas
(4) Bacillus
Two plants can be conclusively said to belong to the same species if they:
(1) can reproduce freely with each other and form viable seeds
(2) have more than 90 percent similar genes
(3) look similar and possess identical secondary metabolites
(4) have same number of chromosomes
The rod shaped cells of Bacillus megatarium are converted to spherical units called protoplasts on treatment with the enzyme
(1) lysozyme
(2) cellulase
(3) cellulase and hemicellulase
(4) cellulase, hemicellulase and pectinase
The kingdom protista does not include
(1) photosynthetic organisms
(2) flagellate organisms
(3) parasitic organisms
(4) bacteria
A lichen that grows by branching is described as
(1) fruticose
(2) crustose
(3) foliose
(4) dichotose