Complete questions on Coloring sheet for tomorrow Complete

• Complete questions on Coloring sheet for tomorrow. • Complete ‘Scramble Words’ Vocabulary sheet for Wednesday. • Quiz on Thursday on the vocabulary for Annelida

The segmented worms “annelus” - little ring I’m metameric

3 classes of Annelida Class Polychaeta – mostly marine fanworms, bristle worms, tube worms

Feather duster worms ( Polychaetes) Filter feeder

Class Oligochaeta - earthworms

Class Hirudinea - leeches

General characteristics • segmented body • coelomate

• Bilateral symmetry • Longitudinal and circular muscles • Setae/ bristles used for locomotion • Soft bodies – hydrostatic skeleton Respiration: • In feather duster worms – gills • Earthworms – moist skin

Specialized structures: Ex. Earthworm • Prostomium – used for sensing and digging through the soil.

• Earthworms have a closed circulatory system: • Blood flow in blood vessels – dorsal and ventral. • They have 5 pumping ‘hearts’ called pseudo-hearts or aortic arches. (Color red)

Segments

• Digestive system: Mouth, Pharynx, Esophagus, • Crop (store food), gizzard (ground up food), intestine (digestion), anus (excretion) Color Green

• Ganglia form ‘brain’. Has a ventral nerve cord. Color Blue • Nephridia for excretion • Clitellum – Secretes mucous ring for fertilization.

Nephridia – Helps with excretion of nitrogen containing wastes.

Reproduction: Example - Earthworm • Sexual reproduction • Hermaphrodites – Male and Female reproductive structures. Eggs produced in ovaries • Worms exchange sperm: Sperm produced in testes. Seminal receptacles receive the sperm from the other worm during mating. Seminal vescicles store sperm from other worm. • External fertilization in a mucous ring which becomes a cocoon. Mucous ring forms at clitellum.

Male Female

http: //www. sciencelearn. org. nz/Science-Stories/Earthworms/Sci-Media/Video/Physical-adaptations-for-life-underground

Mode of nutrition: Some are filter feeders – Tube worms Some are carnivores – Nereis Earthworms feed on decaying vegetation.

Movement: • Body muscles and a hydrostatic Skeleton. • Marine annelids have parapodia Used for swimming and crawling • Earthworms have bristle like Setae to help with movement.