Molluscs PDF Guide

5. PHYLUM: MOLLUSCS MÄKKÝŠE General characteristics ◦Triblastica ◦real coelom – true body cavity ◦soft, non-segmented ◦parts of body: ◦Head ◦muscular foot – may be modified ◦visceral mass ◦Mantle cavity between mantle and body Body systems ◦IS: epidermis, mucus glands ◦MS: smooth muscles on...

5. PHYLUM: MOLLUSCS MÄKKÝŠE General characteristics ◦Triblastica ◦real coelom – true body cavity ◦soft, non-segmented ◦parts of body: ◦Head ◦muscular foot – may be modified ◦visceral mass ◦Mantle cavity between mantle and body Body systems ◦IS: epidermis, mucus glands ◦MS: smooth muscles on foot (modified to tentacles) Body systems ◦DS: complete digestive channel (mouth-anus with the opening to mantle cavity ◦Radula – rough grater- like tongue ◦hepatopancreas Body systems ◦RS: gills, pulmonary sacs ◦CS: open!, haemolymph, heart – 1 ventricle, atrium(-a) ◦ES: metanephridium Body systems ◦NS: ganglaited, specialized ◦SS: eyes, haptic organs ◦RS: gonochorists or hermaphrodites ◦internal fertilization ◦direct or indirect (through larva) development importance ◦Intermediate hosts ◦Source of food ◦Production of shells and peals ◦pests A. Subphulum amphineura ◦Primitive marine organisms ◦No shell ◦No eyes or tentacles B. Subphylum conchifera ◦Shell of CaCO3 ◦3 classes: ◦Gastropoda ◦Bivalvia ◦Cephalopoda a. Class gastropoda (ulitníky) ◦ assymetrical ◦ shell – spiral-coiled ◦ head with eyes and tentacles ◦ modified muscular foot ◦ gonochorist or hermaphrodites (proterandrous), lay eggs ◦ torsion representatives ◦Carpathian blue slug /Bielzia coerulans (slizniak karpatský) ◦White-lipped snail (Cepaea hortensis/slimák meňavý) ◦Edible snail (helix pomatia/slimák záhradný) ◦Garden slug (Agriolimax agrestis/slizniak poľný) representatives ◦Great ramshorn (Planorbarius corneus/kotúľka veľká) ◦Viviparus viviparus (močiarka živorodá) ◦Great pond snail (Lymnea stagnalis/ vodniak vysoký) b. Class bivalvia (lastúrniky) ◦only aquatic, RS: gills ◦shell – 2 valves (ligament, muscles) ◦lack head, radula ◦siphons ◦filter feeders ◦gonochorists, indirect development representatives ◦Swan mussel (Anodona cygnaaea/ škľabka veľká) ◦Painter‘s mussel (Unio pictorum/korýtko rybničné) c. Cephalopoda (hlavonožce) ◦ only marine ◦ no shell (or reduced - cuttlebone) ◦ carnivorous ◦ movement - jet-propulsion system ◦ muscular foot changed into tentacles (with suckers) ◦ gills ◦ CS: closed General characteristic ◦ well developed NS ◦ ink sac ◦ chamber eye ◦ change of colour, luminescence ◦ gonochorists, hectocotylus, direct development ◦ intelligent (learning, memory) representatives ◦Chambered nautilus (Nautilus pompilius/lodienka) ◦Common cuttlefish (Sepia officinalis/ sépia obyčajná) ◦Common octopus (Octopus vulgaris/osmonoh pobrežný) STUDY