Multiple Choice Questions

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Outer wall of pollen grain is made up of

  • Cellulose

  • Sporopollenin

  • Pectocellulose

  • Lignin


B.

Sporopollenin

A pollen grain contains two-layered cell wall, the outer exine and inner intine. Sporopollenin is found in the exine of pollen grains, which is the most resistant biological material known, of microbial and chemical decomposition. Due to this, pollen grains are well preserved during fossilization. Intine of pollen grain is made up of pectocellulose.


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Which extraembryonic membrane in humans prevents desiccation of the embryo inside the uterus?

  • Chorion

  • Allantois

  • Yolk sac

  • Amnion


A transgenic food crop, which may help in solving the problem of nightblindness in developing countries is

  • Flavr savr tomatoes

  • Starlink maize

  • Bt soyabean

  • Golden rice


Polyploidy can be induced by the application of

  • Auxin

  • Kinetin

  • Colchicine

  • Ethylene


Which of the following bio-engineered bacteria is utilized for cleaning of marine oil slicks?

  • Escherichia coli

  • Pseudomonas syringae

  • Pseudomonas putida

  • Rhizoctonia solani


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Cells obtained from cancerous tumours are known as

  • Hybridomas

  • Myelomas

  • Lymphocytes

  • Monoclonal cells


Which of the following is a total root parasite?

  • Cuscuta

  • Rafflesia

  • Santalum

  • Monotrapa


When pollen tube enters through micropyle, the process is called

  • Porogamy

  • Chalazogamy

  • Mesogarny

  • Apogamy


DNA replication occurs in

  • G1-phase

  • S-phase

  • G2-phase

  • M-phase


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AIDS virus contains

  • RNA with protein

  • DNA with protein

  • DNA without protein

  • bNA only