BIOL 2325 Lecture Notes - Lecture 5: Caudofoveata, Solenogastres, Symmetry In Biology
Document Summary
Feeding, cephalic sensory, locomotor organs, muscular actions. Head has a mouth, radula, sensory organs, and foot. Creeping movement via waves of muscular contractions(slimetrack aids) Mantle-sheath of skin that protects soft parts of body. The exposed surface is used for gas exchange. Shell has 3 layers: periostractum, middle prismatic, nacre. Small low rounded shells and creeping foot. Eggs released in strings or masses of jelly and sperm can enter gill groves(dioecious) Feeds on detritus via mucus-covered ciliated tentacle or foot. Respiratory water circulates through mantle via foot. Heavy shells, sluggish and univalve shell, coiled or uncoiled. Operculum-hard proteinaceous plate covering shell aperture when body withdrawals. Torsion-twisting process during development which renders visceral mass asymmetrical. After torsion the anus and mantle are above mouth and nerve cord forms a figure 8. Fouling-waste washing over gills(occurs because of torsion) Coiling -spiral winding of shell and visceral mass(occurs at the same time as torsion) Feeding using radula and digestion is extracellular.
