Tadpoles of frog can be made to grow as giant sized tadpoles, if they are
administered antithyroid substance like thiourea
administered large amounts of thyroxine
reared on a diet rich in egg yolk
reared on a diet rich in both egg yolk and glucose.
A.
administered antithyroid substance like thiourea
Thyroxine, the principal hormone, of thyroid gland, is required for tissue differentiation and metamorphosis (the rapid transformation from the larval to the adult form) in amphibians. Thyroxine triggers a response from the hypothalamus, (probably by a genetic mechanism) followed by the production and release of TSH (Thyroid stimulating hormone), thus metamorphosis begins and tadpoles metamorphose into frogs. Thiourea is an organic compound of carbon, nitrogen, sulphur and hydrogen, with the formula CSN2H4, or (NH2)2CS. It is similar to urea, except that oxygen atom is replaced by a sulphur atom.
seed plants showing abnormal forms of growth and development
plants described only in fossil state
plants described in the literature but which Bentham and Hooker did not see in original
a few orders which could not be placed satisfactorily in the classification.
Myxomycetes are
saprobes or parasites, having mycelia, asexual reproduction by fragmentation, sexual reproduction by fusion of gametes
slimy mass of multinucleate protoplasm, having pseudopodia-like structures for engulfing food, reproduction through fragmentation or zoospores
prokaryotic organisms, cellular or acellular, saprobes or autotrophic, reproduce by binary fission
eukaryotic, single-celled or filamentous, saprobes or autotrophic, asexual reproduction by fusion of two cells or their nuclei.
The given figure shows an angiogram of the coronary blood vessel. Which one of the following statements correctly describes, what is being done
It is coronary artery which has a cancerous growth that is being removed.
It is coronary artery which is blocked by a plaque and the same is being cracked.
It is coronary vein in which the defective valves are being opened.
It is coronary vein blocked by a parasite (blood fluke) that is being removed.
Avena curvature test is a bioassay for examining the activity of
auxins
cytokinins
gibberellins
ethylene.
In the sieve elements, which one of the following is the most likely function of P-proteins
Deposition of callose on sieve plates
Providing energy for active translocation
Autolytic enzymes
Sealing mechanism on wounding
In prokaryotes, chromatophores are
specialized granules responsible for colouration of cells
structures responsbile for organizing the shape of the organism
inclusion bodies lying free inside the cells for canying out various metabolic activities
internal membrane systems that may become extensive and complex in photosynthetic bacteria
A scion is grafted to a stock. The quality of fruits produced will be determined by the genotype of
stock
scion
both stock and scion
neither stock nor scion.
Grafting is successful in dicots but not in monocots because the dicots have
vascular bundles arranged in a ring
cambium for secondary growth
vessels with elements arranged end to end
cork cambium
The function of leghaemoglobin during biological nitrogen fixation in root nodules of legumes is to
convert atmospheric N2 to NH3
convert ammonia to nitrite
transport oxygen for activity of nitrogenase
protect nitrogenase from oxygen
