Multiple Choice Questions

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Which of the following groups of algae produces algin?

  • Phaeophyceae and Chlorophyceae

  • Rhodophyceae and Phaeophyceae

  • Chlorophyceae and Rhodophyceae

  • Phaeophyceae only


D.

Phaeophyceae only

Alginic acid(or algin or alginate) is an anionic polysccharide distributed widely in the cell walls of many brown algae (Phaeophyceae). It is a phycocolloid which is obtained commercially from Laminaria, Macrocystis, Nereocystis, Fucus, Sagrassum etc.


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Gametophyte and sporophyte are independent of each other in which of the following groups?

  • Pteridophytes

  • Angiosperms

  • Gymnosperms

  • Bryophytes


Which of the following is not an invasive species?

  • Parthenium hysterophorus

  • Nelumbo (lotus)

  • Lantana camara

  • Eichhornia crassipes


Occurrence of triploid (3n) primary endosperm nucleus is a characteristic feature of

  • Algae

  • Gymnosperms

  • Angiosperms

  • Bryophytes


Assertion: Presence of large amounts of nutrients in water body causes excessive growth of planktonic algae.

Reason: It is due to biomagnification.

  • 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.


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Assertion : Sphagnum is slowly carbonised, compressed and fossilised over thousands of years to produce a dark spongy mass called peat.

Reason : Peat helps to keep soil porous and it also improves water holding capacity of the soil.

  • 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


In which of the following sets of organisms, does the external fertilization occur?

  • Echinodermata and mosses

  • Hemichordata and ferns

  • Amphibians and algae

  • Reptiles and gymnosperms


Which of the given genera is homosporous

  • Cycas

  • Pinus

  • Selaginella

  • Lycopodium


Assertion: The leaves in gymosperms are well adapted to with stand extremes of temperature, humidity and wind.

Reason: Unlike bryophytes and pteridophytes, in gymnosperms the male and female gametophytes do not have an independent free-living existence.

  • 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.


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Assertion: In basidiomycetes, basidiospores are produced endogenously in the basidium.

Reason: In ascomycetes, ascospores are produced exogenously in ascus.

  • 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.


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