Provide appropriate technical term in the space provided.

1.  Blood-filled cavity in arthropods.........

2.  Free-floating form Of Cridaria ..........

3.  Stinging organ of jelly fishes ..........

4.  Lateral appendages in aquatic annelids .........

 

 
(a) Haemocoel is the blood-filled cavity in arthropods containing haemolymph.
 
(b) Medusa is a form in cnidarians in which the body is shaped like an umbrella which can float freely in sed water
 
(c) Nematocytes are capsules of specialised cells in cnidarians which act as a paralysing Sting.
 
(d) Parapodia are the paired unjointed lateral outgrowth in annelids bearing chaetae.