Multiple Choice Questions

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Assertion: Endomycorrhiza of forest trees contribute to the efficient nutrient cycling in tropical forest ecosystems.

Reason: The fungi that formendo-mycorrhizal associations with plants make nutrient ions available to them.

  • 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.


A.

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

The fungi of endomycorrhiza invade the cells of the root cortex, with a portion lying externally as a loose mass of hyphae in the soil. Mycorrhiza cause considerable stimulation of growth in nutrient deficient soil. The greatest stimulation occurs in the uptake of phosphates. Mycorrhiza can take up phosphate at that low concentrations at which they are unavailable to nonmycorrhizal roots.


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Pick the correct group consisting of all genera exhibiting homospory

  • Lycopodium, Psilotum, Selaginella, Equisetum

  • Equisetum, Pteris, Salvinia, Psilotum

  • Salvinia, Pteris, Lycopodium, Selaginella

  • Equisetum, Psilotum, Lycopodium, Pteris


Which of the following are homosporous pteridophytes?

I. Selaginella

II. Lycopodium

III. Salvinia

IV. Equisetum

  • I and IV only

  • II and III only

  • II and IV only

  • III and IV only


Select the mismatched pair out of the following

  • Rhizome - Dryopteris, Nelumbo nucifera

  • Corm - Crocus sativus, Amorphophallus

  • Sucker -Curcuma domestica, Zingiber officinale

  • Tuber -Helianthus tuberosus, Solanum tuberosum


'Gymnosperm' have how many species?

  • 1000

  • 900

  • 640

  • 300


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Match the following and select correct option.

  Column1        Column2

A. Pteris           1) Gymnosperm

B. Cycas           2) Bryophyte

C. Sphagnum    3) Algae

D. Sargassum   4) Pteridophyta

  • A-(4), B-(2), C-(1), D-(3)

  • A-(4), B-(1), C-(2), D-(3)

  • A-(2), B-(3), C-(4), D-(1)

  • A-(1), B-(4), C-(3), D-(2)


The lack of fruit formation in gymnosperm is due to

  • absence of fertilization

  • lack of seeds

  • naked ovule

  • sheding of immature seed


Pneumatophores (respiratory roots) are found in

  • Pistia

  • Calobranchia

  • Rhizophora

  • All of these


Select one of the following pairs of important features distinguishing Gnetum from Cycas and Pinus and showing affinities with angiosperms

  • Perianth and no integuments

  • Embryo development and apical meristem

  • Absence of resin duct and leaf venation

  • Presence of vessel elements and absence of archegonia


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'Club moss' is the common name of

  • Selaginella

  • Funaria

  • Potamogeton

  • Lycopodium


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