In which of the following is Segmentation in the body first observed:(a) Platyhelminthes (b) Aschelminthes (c) Annelida (d) Arthropoda.

6 How important is the presence of air bladder in Pisces? 7 What are the modifications that are observed in birds that help them fly? 9 Match the following:

Column I	Column II
(i) Operculum	(a) Ctenophora
(ii) Parapodia	(b) Mollusca
(iii) Scales	(c) Porifera
(iv) Comb plates	(d) Reptilia
(v) Radula	(e) Annelida
(vi) Hairs	(f) Cyclostomata and Chondrichthyes
(vii) Choanocytes	(g) Mammalia
(viii) Gill slits	(h) Osteichthyes

   10 List some parasitic animals that are found on human beings.