80 likes | 279 Views
Phylum annelida. The Segmented Worms. Internal anatomy. https:// www.youtube.com/watch?v=u9HHS1uPFSo. Internal anatomy. Hirudinea – the leeches. Note the adaptation of the mouth to the parasitic niche of the leeches
E N D
Phylum annelida The Segmented Worms
https://www.youtube.com/watch?v=u9HHS1uPFSo Internal anatomy
Hirudinea – the leeches • Note the adaptation of the mouth to the parasitic niche of the leeches • Note also the segmentation which makes it similar to the other annelid worms
Hirudinea – The leeches • This leech has an anterior sucker for feeding and a posterior sucker for attachment • https://www.youtube.com/watch?v=ye4N2ZeJESA
Class Polychaetae • Note the parapodia • Parapodia are expanded groups of structures (including lobes and setae) used for locomotion and gas exchange • Note also the specialization of segments and well developed cephalization • https://www.youtube.com/watch?v=kIoN2PCvL4o • https://www.youtube.com/watch?v=UuApLH8rlwY
Class oligochaetae – the earthworms • Note the clitellum – a reproductive structure that will form a protective case for the eggs & larvae • Note the specialization of anterior and posterior segments • https://www.youtube.com/watch?v=uO4lkv-jLRs
Earthworm reproduction • Earthworms are monoecious (hermaphroditic), but cannot self-fertilize • https://www.youtube.com/watch?v=bFpblBf1dfE