Multiple Choice Questions

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Ozone depletion in stratosphere would result in

  • forest fires

  • global warming

  • skin cancer incidence

  • None of the above


C.

skin cancer incidence

In the stratosphere, about 30 km above the earth surface, the ozone layer molecules (O3) form an umbrella. It prevents the penetration of harmful ultra violet radiation from the sun and thus protects the life of the earth. 

Ozone is odourless, invisible, that is why it is widely used in domestic refrigerators and cold storage facilities. It is calculated that the depletion of ozone layer by 1% results in an increase in the incidence of skin cancer by 5% to 7%.


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DNA multiplication is called

  • translation

  • replication

  • transduction

  • transcription


Stop codons are

  • AUG, GUG

  • UAA, UGA, UAG

  • UAC, UGG

  • AGU, AGA, UAC


Foolish seedling disease of rice in Japan was caused by
  • the deficiency of nitrogen

  • a bacterium

  • a fungus

  • a virus


In rabbit, head of epididymis present at the head of the testis is called

  • vas deferens

  • cauda epididymis

  • gubernaculum

  • caput epididymis


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Which of the following is a test cross ?

  • Tt x tt

  • TT x tt

  • Tt x Tt

  • tt x tt


1 : 2 : 1 phenotypic and genotypic ratio is found in

  • complementary genes

  • blending inheritance

  • multiple alleles

  • pseudo alleles


Jumping genes in maize were discovered by

  • Hugo de Vries

  • Barbara McClintock

  • TH Morgan

  • Mendel


The embryo at 16 celled stage is known as

  • morula

  • gastrula

  • blastula

  • blastomere


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Cleavage polyembryony occurs in

  • Pinus

  • Mini Cycas

  • Cycas

  • Ephedra