Multiple Choice QuestionsSome of the characteristics of Bt cotton are
long fibre and resistance of aphids
medium yield, long fibre and resistance to beetle pests
high yield and production of toxic protein crystals which kill dipteran pests
high yield and production of toxic protein crystals which kill dipteran pests
D.
high yield and production of toxic protein crystals which kill dipteran pests
Bacillus thuringiensis forms crystals containing a toxic insecticidal protein. Bt toxin protein exists as an inactive toxin, it is converted into an active form of toxin due to the alkaline pH of the gut, which solubilises the crystals. The activated toxin binds to the surface of midgut epithelial cells and creates pores the cause cell swelling and lysis and eventually cause the death of the insect. Specific Bt toxin genes were isolated from B. thruingiensis and incorporated into the several plants such as cotton. The toxin is coded by the gene name cry. There is a number of them, eg, the proteins encoded by the genes cry IAc a cry II Ab control the cotton bollworms, that of cry IAB control corn borers.
Which one of the following proved effective for biological control of nematodal diseases in plants?
Pisolithus tinctorius
Pseudomonas cepacin
Gliocladium virens
Gliocladium virens
Farmers in a particular region were concerned that pre-mature yellowing of leaves of a pulse crop might cause decrease in the yield. Which treatment could be most beneficial to obtain maximum seed yield?
Frequent irrigation of the crop
Treatment of the plants with cytokinins alongwith a small dose of nitrogenous fertilizer
Removal of all yellow leaves and spraying the remaining green leaves with 2,4,5- trichlorophenoxy acetic acid
Removal of all yellow leaves and spraying the remaining green leaves with 2,4,5- trichlorophenoxy acetic acid
Microbes found to be very useful in genetic engineering are
Escherichia coli and Agrobacterium tumefaciens
Vibrio cholerae and a tailed bacteriophage
Diplococcus sp. and Pseudomonas sp
Diplococcus sp. and Pseudomonas sp
Triticale, the first man-made cereal crop, has been obtained by crossing wheat with
rye
pearl millet
sugarcane
sugarcane
Female cone of Pinus is a
Modified needles
Modified long shoot
Modified dwarf shoot
Modified scale
Which statement is correct for bacterial transduction?
Transfer of some genes from one bacteria to another bacteria through virus
Transfer of genes from one bacteria to another bacteria by conjugation.
Bacteria obtain DNA directly
Bacteria obtain DNA from other external sources
Which of the following is not true for a species?
Members of a species can interbreed
Variations occur among members of species
Each species is reproductively isolated from every other species
Gene flow does not occur between the populations of a species
One gene- one enzyme hypothesis of Beadle and Tatum was experimentally proved on
Saccharomyces
Neurospora crassa
Lathyrus odoratus
Claviceps
Genes for cytoplasmic male sterility in plants are generally located in
mitochondrial genome
cytosol
chloroplast genome
nuclear genome
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