During unfavourable conditions, the sponges form

• cyst

• encyst

• spicule

• Gemmule

Shell of molluscs is derived from

• foot

• mantle

• ctenidia

• placoid

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

• Thesocytes

• Pinacocytes

• Cnidocytes

• Archaeocytes

Connecting link between annelids and molluscs is

• Neopilina

• Peripatus

• Periplaneta

• Limulus

Which of the following have notochord throughout life?

• Birds

• Fish

• Snake

• Amphioxus

Sea gulls excrete excess of NaCl from

• liver

• lungs

• nasal activity

• kidney

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

• biothermic

• poikilothermic

• oligothermic

• homeothermic

Ruminants belong to order

• Proboscida

• Artiodactyla

• Marsupials

• Edentata

The echinoderms are

• arborial insects

• marine animals

• terrestrial insects

• freshwater forms

Tube feet is the locomotory organ in 

• starfish

• jelly fish

• silver fish

• Scoliodon