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Multiple Choice Questions

Intermediate host is absent in the infection of

  • Plamosdium

  • Trypanosoma

  • Entamoeba

  • Filarial worm


Thermococcus, Methanococcus and Methanobacterium exemplify

  • bacteria whose DNA is relaxed or positively supercoiled but which have a cytoskeleton as well as mitochondria

  • bacteria that contain a cytoskeleton and ribosomes

  • archaebacteria that contains protein homologous to eukaryotic core histones

  • archaebacteria that lack any histones resembling those found in eukaryotes but whose DNA is negatively supercoiled


Assertion: Protoplasmic continuity is maintained in perforated septum.

Reason: Usually a small pore remains in the centre of the septum.

  • 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.


Assertion: The primary protenema of moss by death and decay of cells may break into fragments.

Reason: Each fragment gives rise to leafy gametophyte.

  • 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 : Neurospora is commonly called water mould.

Reason : It belongs to basidomycetes fungi.

  • 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


Based on cellular mechanisms there are two major types of regeneration found in the animals. Which one of the following is the correct example of the type mentioned?

  • Morphallaxis - Regeneration of two transversely cut equal pieces of a Hydra into two small Hydras

  • Epimorphosis - Replacement of old and dead erythrocytes by the new ones

  • Morphallaxis - Healing up of a wound in the skin

  • Epimorphosis - Regeneration of crushed and filtered out pieces of a Planaria into as many new Planarians


Myxomycetes are

  • saprobes or parasites, having mycelia, asexual reproduction by fragmentation, sexual reproduction by fusion of gametes

  • slimy mass of multinucleate protoplasm, having pseudopodia-like structures for engulfing food, reproduction through fragmentation or zoospores

  • prokaryotic organisms, cellular or acellular, saprobes or autotrophic, reproduce by binary fission

  • eukaryotic, single-celled or filamentous, saprobes or autotrophic, asexual reproduction by fusion of two cells or their nuclei.


Electroporation procedure involves

  • fast passage of food through sieve pores in phloem elements with the help of electric stimulation

  • opening of stomata! pores during night by artificial light

  • making transient pores in the cell membrane to introduce gene constructs

  • purification of saline water with the help of a membrane system


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The bacteria Pseudomonas aeruginosa is useful because of its ability to

  • transfer genes from one plant to another

  • decompose a variety of organic compounds

  • fix atmospheric nitrogen in the soil

  • produce a wide variety of antibiotics


Assertion : The fungi are widespread in distribution and they even live on or inside other plants and animals.

Reason : Fungi are able to grow anywhere on land, water or on other organisms because they have a variety of pigments, including chlorophyll, carotenoids, fucooxanthin and phycoerythrin.

  • If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion

  • If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion

  • If Assertion is true but Reason is false

  • If both Assertion and Reason are false


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