MOLLUSCS Vukov materil OR 03 69 Tvrce Mgr
- Slides: 19
MOLLUSCS Výukový materiál OR 03 - 69 Tvůrce: Mgr. Alena Výborná Tvůrce anglické verze: Th. Mgr. Ing. Jiří Foller Projekt: S anglickým jazykem do dalších předmětů Registrační číslo: CZ. 1. 07/1. 1. 36/03. 0005 Tento projekt je spolufinancován ESF a SR ČR
MOLLUSCS • A very diverse group • They live mostly in the sea but also in the fresh water and on the mainland • Skin fold of the body = mantle ▫ It excretes calcareous substances from which their mantles are formed • Mantle protects the soft body
MOLLUSCS
MOLLUSCS • Orientation in the habitat at a different level according to their lifestyle: ▫ ▫ touch cells (slowly moving) smell cells checking the location sight organs �simple eyes �chamber eye
MOLLUSCS • GASTROPODA • BIVALVIA • CEPHALOPODA
GASTROPODA (SNAILS) • marine, freshwater, terrestrial • they move slowly muscular foot • muscular foot contains glands which excrete mucus; it makes the movement of terrestrial gastropoda easier • most body is covered by a solid conch • mostly gonochorists • some of them hermaphrodites
GASTROPODA
GASTROPODA • They consume both plant and animal food • A few species predators • Breathing: ▫ water �oxygen dissolved in the water (river snail) �air oxygen – they swim to the water level (great pond nail, great ramshorn snail) ▫ terrestrial �air oxygen
GASTROPODA • burgundy Snail • white lipped banded snail • slug • large red slug • great pond snail • river snail • great ranshorn snail
BIVALVIA (MUSSELS) • water molluscs (freshwater, saltwater) • the body is covered by a shell consisting of two parts • the inner side of the shell is made of a nacre layer • some bivalvia live attached to hard surfaces • they feed with phytoplankton
BIVALVIA • oyster • scallop • mussel • cockle • pearl oyster • clam
CEPHALOPODA • marine • predators • foot modified into arms (tentacles; 8 – 10) with suckers • the rest of arm transformed into a funnel • eyes – perfectly evolved • there is no mantle ▫ the relic – cuttlebone (sepia) ▫ nautilus - mantle
CEPHALOPODA • cuttlefish • squid • octopus • nautilus
REVISION: • 1) The body of bivalvia is protected by? ▫ Shell • 2) The body of gastropoda is protected by? ▫ Conch • 3) Individual with both the sexual organs is called? ▫ Hermaphrodite • 4) A gonochorist is? ▫ An individual that has either male or female sexual organs. • 5) Squid belongs to? ▫ Cephalopoda
SOURCE: • DOBRORUKA, Luděk J. Přírodopis pro 7. ročník základní školy. 1. vyd. Praha: Scientia, 1998, 152 s. ISBN 80 -718 -3134 -4