Multiple Choice Questions

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Antifeedant property occurs in

  • nicotine

  • azadiractin

  • rotenone

  • cinerin


B.

azadiractin

Antifeedants are organic compound produced by plants to inhibit attack by insects and grazing animals. These chemical compounds are typically classified as secondary metabolites in that they are not essential for the metabolism of the plant, but instead confer longevity. Antifeedants exhibit a wide range of activities and chemical structures as biopesticides.

 Azadirachtin are extract of neem tree, it has several effects on phytophagous insects and is thought to disrupt insect molting by antagonizing the effects of ecdysteroids. This effect is independent of feeding inhibition, which is another observed effect of the compound.1,10 The antifeedant/repellent effects are dramatic, with many insects avoiding treated crops, although other chemicals in the seed extract, such as salanin, have been shown to be responsible for these effects. 


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The part of an eye which acts like a diaphragm of a photographic camera is

  • pupil

  • iris

  • lens

  • cornea


Antibiotic flavicin is obtained from

  • Aspergillus flavus 

  • Aspergillus clavatum

  • Streptomyces grieseus

  • Streptomyces fradiae


'Climacteric' is

  • a phenomenon related to fruit ripening

  • the condition of a plant when all its fruits are almost ripe

  • the condition of a plant when most of its leaves have turned yellow

  • none of the above


The crystal of lead zirconate is a key component of

  • sonography

  • electrocardiography

  • electroencephalography

  • magnetoencephalography


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Cochlea of mammalian internal ear is concerned with

  • hearing

  • balance of body posture

  • both (a) and (b)

  • perception changes of atmospheric pressure


Which is not a gonadal hormone

  • Progesterone

  • Testosterone

  • Adrenalin

  • Estrogen


Cerebrospinal fluid is present

  • beneath the pia mater

  • between piamater and arachnoid

  • between arachnoid and duramater

  • between duramater and cranium


The dendrite carries impulses

  • towards the cyton

  • away from cyton

  • across the body

  • from one neuron to another


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Ethylene is a

  • gaseous hormone

  • gaseous enzyme

  • liquid-gas mixture

  • solid hormone