Multiple Choice Questions

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Somaclones are prepared by

  • callus culture

  • sexual reproduction

  • micropropagation

  • somatic hybridisation


C.

micropropagation

Somaclones are genetically identical (Clones) plants developed from any part of a plant by tissue culture/micropropagation. This type of micropropagation is also called somaclonal propagation.


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How many haploid nuclei are present in a mature pollen grain

  • One

  • Two

  • Three

  • Four


The total number of biodiversity hotspots in the world are

  • 72

  • 34

  • 52

  • 24


Assertion: Adrenocorticotropic-Releasing Hormones (ARH) excite the anterior lobe of
pituitary gland to produce adrenocorticotropic hormone (ACTH).

Reason: ACTH stimulates the adrenal cortex to secrete its glucocorticoid and mineralocorticoid hormones.

  • If both assertion and reason are true and reason is the correct explanation of assertion.

  • If both assertion and reason are true but reason is not the correct explanation of assertion.

  • If assertion is true but reason is false.

  • If both assertion and reason are false.


During menstrual cycle, levels of LH and estrogen are highest around

  • 14day

  • 21day

  • 7day

  • 28day


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In cloning of cattle a fertilized egg is taken out of the mother's womb and

  • in the eight cell stage, cells are separated and cultured untill small embryos are formed which are implanted into the womb of other cows

  • in the eight cell stage the individual cells are separated under electrical field for further development in culture media

  • from this upto eight identical twins can be produced

  • the egg is divided into 4 pairs of cells which are implanted into the womb of other cows.


Assertion: Pulmonary circulation consists of flow of deoxygenated blood from right ventricle to the lungs and flow of oxygenated blood from lungs to the left atrium.

Reason: Systemic circulation consists of flow of oxygenated blood from the left ventricle to all parts of the body and deoxygenated blood from different parts to right atrium.

  • If both assertion and reason are true and reason is the correct explanation of assertion.

  • If both assertion and reason are true but reason is not the correct explanation of assertion.

  • If assertion is true but reason is false.

  • If both assertion and reason are false.


Which of the following associations shows mutualism

  • Fig and wasp

  • Barnacles on whale

  • Roundworms in human intestine

  • Orchids on mango tree


Which of the following occurs due to monosomy of sex chromosome

  • Down's syndrome

  • Turner's syndrome

  • Haemophilia

  • Sickle cell anaemia


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Plants do not get benefit from

  • N2 in air

  • O2 in air

  • CO2 in air

  • O3 in air