The worker honey bee normally lives for about
The worker honey bee normally lives for about 90 days.
Which one of the following statement is correct in relation to honey bees?
Karl Von Frisch, carried out many experiments and determined that when a foraging bee returns to the hive, it performs a waggle dance. Honey is predominantly glucose and fructose. Dorsata is a biger bee than Apis indica (a medium sized bee). Bees wax is secreted by special wax glands to make compartments.
What is the best pH of soil for cultivation of plants?
The best pH of soil for cultivation of plants is 6.5 – 7.5.
Before European invader which vegetable was absent in India?
Potato and tomato originated in the new world.
In Lederberg's replica experiment what shall be used to obtain streptomycin-resistant strain?
This combination allows to select only streptomycin resistant strains and non resistant strains would die on medium containing antibiotic streptomycin.
Which of the following crops have been brought to India from New world?
Cashewnut, potato, rubber crops have been brought to India from New world.
Reason of fast speciation in present day crop plants is
The phenomenon of having one or more genomes in addition to the normal for the species is called polyploidy.
In tissue culture medium, the embr yoids formed from pollen grains is due to
Cellular totipotency is the ability, shown by many living cells to form all types of tissue that constitute the mature organism.
Which endangered animal is the source of world's finest, lightest, warmest and most expensive wool the shahtoosh ?
Which of the following plants are used as green manure in crop fields and in sandy soils ?
Crotolaria juncea and Alhagi camelorum are among the plants which are used as green manures in India. These green manures help the soil through increasement of area and water holding capacities and fertility. Correct Answer is C.
Cellular totipotency is demonstrated by
Cellular totipotency is exhibited only by plant cells wherein the plant cells retain the ability to deactivate and form the new dividing cells.
India’s wheat yield revolution in the 1960s was possible primarily due to
Green revolution was possible due to hybridization. Increased chlorophyll extent has no effect on yield of crops. Hybrid plants were dwarf because of selection. Quantitative trait mutations are not involved in hybridization.
In 1963, ICAR introduced many selections from CIMMYT include those developed by Norman Borlaugh using Norin-10 as the source of dwarfing genes (CIMMYT-Centro International de Mejoramiento de Maiz Y Trigo).
The most likely reason for the development of resistance against pesticides in insects damaging a crop is
According to Darwin resistance to pesticides has a genetic basis due to presence of certain alleles. In the presence of pesticides, the insects devoid of the allele for resistance die while the ones having them survive. They are selected by nature.
The water potential of pure water is
Three crops that contribute maximum to global food grain production are
Three crops that contribute maximum to global food grain production are Wheat, rice and maize, which belong to the family Poaceae (Graminae).
The world’s highly prized wool yielding 'Pashmina' breed is
The world’s highly prized wool yielding Pashmina breed is the under fur of Kashmiri and Tibetan goats.
Pashmina is an almost generic name for accessories made from a type of mohair that is obtained from a special breed of goat indigenous to high altitudes of the Himalayan Range Belt of Asia.
The name comes from Pashmineh, made from Persian pashm (= “wool”).
The special goat’s fleece has been used for thousands of years to make high-quality shawls that also bear the same name.
In order to obtain virus-free plants through tissue culture the best method is
Meristem culture is done for the development of virus free plants. Meristematic tissue cell can be taken either from shoot or root tip.
Crop plants grown in monoculture are
Crop plants grown in monoculture are highly prone to pests.
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 ?
Because iron promotes the formation of chlorophyll and magnesium is an integral part of chlorophyll molecule so in the absence of these nutrients plants show chlorosis & leaves get yellowing. Application of iron and magnesium to promote the synthesis of chlorophyll can cure the disease.
Triticale, the first man-made cereal crop, has been obtained by crossing wheat with
Triticale is the Ist man made cereal which is made by the crossing of wheat (Triticum aestivum) and Rye (Secale cereale).
Curing of tea leaves is brought about by the activity of
For curing of tea a bacteria Mycococcus candisans is used.
Curing of tea leaves is brought about by the activity of bacteria. It is essentially an oxidation. dry fermentation process, during which water is driven off the green colour is lost and the leaves assume a tougher texture and undergo chemical changes.
Mycorrhiza is mutually beneficial association between fungi and the roots of higher plants. Virus and fungi are not involved in the curing process of tea leaves.
Which one of the following is the most suitable medium for culture of Drosophila melanogaster?
The most suitable culture medium for Drosophila melanogastor is ripe banana.
Drosophila Melanogaster is commonly called as fruitfly and is often used in genetic and developmental biology researches. Moist bread is a culture medium for the fungus Rhizopus while Agar-agar is used as a tissue culture medium.
In maize, hybrid vigour is exploited by
In maize (or in other plants) hybrid vigour in exploited by the crossing of two inbred (very closely related) plants because crossing of inbred varieties causes homozygosity and due to which hybrid vigour will be diminished because in homozygosity so many recessive traits start showing their phenotypic expression.
Parthenocarpic tomato fruits can be produced by
Parthenocar py is the development of fruits without prior fertilization which results in the formation of seedless fruits. In some plant species, parthenocarpic fruits are produced naturally or they may be induced by treatment of the unpollinated flowers with auxin.
Removal of androecium before pollen release is called emasculation which is helpful in preventing unwanted pollination. Vernalized seeds are the child treated seeds for breaking dormancy. Phenyl Mercuric Acetate is an antitranspirant.
Gibberellins and Auxins are known to induce parthenocarpy in plants. If a tomato plant is treated with a low concentration of auxin and gibberellic acid it ’ ll produce fruits with out fertilization i.e. parthenocarpic fruits.
Which one of the following is being utilized as a source of biodiesel in the Indian countryside?
Pongamia pinnata is one of the few nitrogen fixing trees (NFTS) to produce seeds containing 30-40% oil. It is often planted as an ornamental and shade tree but now-a-days it is considered as alternative source for Bio- Diesel. This species is commonly called pongam, karanja, or a derivation of these names. Pongami, jatropa, Euphorbia are petrocrops. However, in the Indian countryside, pongamia(kanjar) is being utilized as a source of biodiesel.