Multiple Choice Questions

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The Montreal Protocol refers to

  • Persistent organic pollutants

  • Global warming and climate change

  • Substances that deplete the ozone layer

  • Biosafety of genetically modified organisms


C.

Substances that deplete the ozone layer

World's major producers and consumers of pollutants met at Montreal (Canada) on September 16, 1987 to solve the problem of ozone thining in stratosphere. 24 countries signed the protocol that came into force on january 1, 1989. This protocol refers to the substances such as CFCs (chlorofluorocarbons), methane that deplete the ozone layer.


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One gene-one enzyme relationship was established for the first time in

  • Neurospora crassa

  • Salmonella typhimurium

  • Escherichia coli

  • Diplococcus pneumoniae


Biological Oxygen Demand (BOD) is a measure of

  • Industrial wastes poured into water bodies

  • The extent to which water is polluted with an organic compound

  • Amount of carbon monoxide inseparably combined with haemoglobin

  • Amount of oxygen needed by green plants during the night 


A polygenic inheritance in human beings is

  • Skin colour

  • Sickle cell anaemia

  • Colour blindness

  • Phenylketonuria


Powdery mildew of wheat is caused by a species of

  • Puccinia

  • Erysphe

  • Ustilago

  • Albugo


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The Okazaki fragments in DNA chain growth

  • Results in transcription

  • Polymerise in the 3' to 5' direction and forms replication fork

  • Prove semi-conservative nature of DNA replication

  • Polymerise in the 5' to 3' direction and explain 3' to 5 DNA replication


Nucleic acid segment tagged with a radiactive molecule is called

  • Clone

  • Probe

  • Plasmid

  • Vector


In gymnosperms, the pollen chamber represents

  • A cell in the pollen grain in which the sperms are formed

  • A cavity in the ovule in which pollen grains are stored after pollination

  • An opening in the megagametophyte through which the pollen tube approaches the egg

  • The microsporangium in which pollen grains develop


Double fertilization occurs in

  • Riccia

  • Pteridium

  • Cycas

  • Capsella


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Ten percent law of energy transfer in a food chain is given by

  • Schimper

  • Elton

  • Haeckel

  • Lindemann