Phylum molluca

phylum Mollusca
my presentation

1. phylum molluca submitted to Maam NOOR FATIMA submitted by SHAHID IQBAL Registration 2019-uam-1212 course FRESH WATER INVERTEBRATE MNS-UNIVERSITY OF AGRICULTURE MULTAN

2. PHYLUM MOLLUSCA Introduction Mollusca latin words moallis means soft body animal proposed by john ston second largest animal phylum Evolution of mollusca 540 years ago combrian period (siberia , china) living50,000species fossil species 35,000

3. Ecology of mollusca Mollusca animal are free living some are sessile Attached of surface body(rock body) Fresh water Marine water Terrestial moist places (land snail)

4. Body characters shelled animal Body is hard, ridig(outer layer) shell is made of calcium carbonate triploblastic (three layer endo ,ecto ,meso) coelomate cavity Bliteral symetery Unsegmented and soft body

5. Body part Head A ventral muscular foot Dorsal viseral mass Mantle present over the visral mass Mantle screte out shell Between shell and mantle contains gills

6. Digestive system Digrstive system consist of gut two opening Mouth, Anus Rasping tongue like structure Rodula many horny teeth used for grinding food

7. Excretory system The excretory organ paired Nephrida Mulluscs well developed excretory system Tubular system kidneys, that collect liquid wastes from the coelom and dump them in the mantle cavity, where they are pumped out of the shell.

8. circulatory system opening circulatory system Except (Cephalopoda) close circulatory coelom is divided into; Sinuses ,Blood space contain blue respiratory pigments called Haemocynin

9. Respiratory system Exchange of gases into gills Mantle cavity is covert into lungs

10. Nervous system Nervous system consist of three pair interconnected ganglia Ganglia present in head ,foot and body regions

11. Reproductive system sexes separate protostomic characteres developed Trochophore larva spiral cleavage

12. locomotions organs of locomotion muscular foot Movement is slow some are sessile

13. classification Mollusca six classes Monoplacophora Amphineura Gastropoda Scaphopoda Pelecypoda (Bivalvia) Cephalopoda

14. Class Gastropoda largest class of mullusca slags ,snial mostly marine some fresh water,terrestial Asymmetrical prominent head and broad muscular foot External shell may present or absent Helix asprsa ( Garden snail) Limax (slags)

15. class Bivalva (pepecypoda) Bilaterally symmetrical Aquatic molluscs plate like gills Marine Mussel Oyster

16. \Economic importance Mullusca use as man food button industry(mussel) making raods (oyster,tar) making Ornaments valuable pearls (oyster)

17. Harm full mulluscs mulluscs are indirectly harmfull to man harmfull Mullusca (Slags,shipworms) slags harmfull gardens and other cultivations Teredo(shipworms)Demag

18. Refference Field Guide to Fresh water invertebrate of North America by James H.Thorp&D 1st year book Doctor biology vedio lecture by Dr Hadi