Multiple Choice Questions

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Which of the following cell type is capable of giving rise to other cell types in sponges?

  • Thesocytes

  • Pinacocytes

  • Cnidocytes

  • Archaeocytes


D.

Archaeocytes

Archaeocytes are the totipotent cells, which provide great regenerating power to sponges. Sex cells (sperm and ova arise from undifferentiated archaeocytes).


Thesocytes are the amoebocytes with reserve food granules.


Pinacocytes are the polygonal flat cells present as outer layer of cells, called pinacoderm lining the spongocoel or body cavity in Leucosolenia.


Cnidocytes occur in entire epidermis except that of basal disc and are found only in cnidarians. These are spherical or oval cells.


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Connecting link between annelids and molluscs is

  • Neopilina

  • Peripatus

  • Periplaneta

  • Limulus


Sea gulls excrete excess of NaCl from

  • liver

  • lungs

  • nasal activity

  • kidney


Ruminants belong to order

  • Proboscida

  • Artiodactyla

  • Marsupials

  • Edentata


Shell of molluscs is derived from

  • foot

  • mantle

  • ctenidia

  • placoid


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Tube feet is the locomotory organ in 

  • starfish

  • jelly fish

  • silver fish

  • Scoliodon


Which of the following have notochord throughout life?

  • Birds

  • Fish

  • Snake

  • Amphioxus


The echinoderms are

  • arborial insects

  • marine animals

  • terrestrial insects

  • freshwater forms


During unfavourable conditions, the sponges form

  • cyst

  • encyst

  • spicule

  • Gemmule


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Animals having a built in thermostat to maintain constant body temperature are known as

  • biothermic

  • poikilothermic

  • oligothermic

  • homeothermic


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