Multiple Choice Questions

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Which one of the following is linked to the discovery of Bordeaux mixture as a popular fungicide?

  • Bacterial leaf blight of rice

  • Downy mildew of grapes

  • Loose smut of wheat

  • Loose smut of wheat


B.

Downy mildew of grapes

Bordeaux mixture was discovered by Millardet in France in 1882. It is prepared by dissolving 40 g of copper sulphate and 40 g of calcium hydroxide in 5 L of water. It was first used to control downy mildew disease of grape-vine that is caused by a fungus Plasmopara viticola. Black rust of wheat is caused by Puccinia graminis Tritici. The use of fungicide Dithane Z- 78 and Dithane M- 45 control the disease even at a lower concentration.
Loose smut of wheat is caused by Ustilago tritici. The use of fungicides (systemic fungicide like D- 735 and F- 461)give the quite encouraging result.

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Which one of the following is the correct difference between rod cells and cone cells of our retina? 

  • Features

    Rod cells

    Cone cells

    Visual acuity

    High

    Low

  • Features

    Rod cells

    Cone cells

    Visual Pigment contained

    Iodeosin

    Rhodopsin

  • Features

    Rod cells

    Cone cells

    Overall function

    Vision in poor light

    Colour vision and detailed vision in bright light

  • Features

    Rod cells

    Cone cells

    Overall function

    Vision in poor light

    Colour vision and detailed vision in bright light

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The rupture and fractionation do not usually occur in the water column in vessel/tracheids during the ascent of sap because of 

  • lignified thick walls

  • cohesion and adhesion

  • weak gravitational pull

  • weak gravitational pull

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The length of different internodes in a culm of sugarcane is variable because of

  • shoot apical meristem

  • position of axillary buds

  • size of leaf lamina at the node below each internode

  • size of leaf lamina at the node below each internode

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The fleshy receptacle of  syconus of fig encloses a number of 

  • achenes

  • samaras

  • berries

  • berries

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The blood calcium level is lowered by the deficiency of 

  • parathormone

  • thyroxine

  • calcitonin

  • calcitonin

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Which one of the followings in birds, indicates their reptilian ancestry?

  • Scales on their hind limbs

  • Four chambered heart

  • Two special chambers crop and gizzard in their digestive tract

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Endosperm is consumed by developing embryo in the seed of 

  • coconut

  • castor

  • pea

  • pea

524 Views

Dry indehiscent single-seeded fruit formed from bicarpellary syncarpous inferior ovary is 

  • Caryopsis

  • cypsela

  • Adiantum

  • Adiantum

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Which one of the following is heterosporous? 

  • Dryopteris 

  • Salvinia

  • Adiantum

  • Adiantum

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