Nemertea Flashcards
what are some general traits for Nemertea?
- has a circulatory system powered by muscle movement
- no respiratory system
- active predators
- stylets
- proboscis
- marine
what are the two classes in Nemertea?
Enopla and Anopla
what are the differences between Enopla and Anopla?
Enopla:
- “armed” = stylets
- mouth ahead of brain
- one opening shared with mouth and proboscis
Anopla:
- “unarmed” = no stylets
- mouth behind brain
- separate openings for mouth and proboscis
what traits separate Nemertea from Platyhelminthes?
- gonochoristic vs. being hermaphoridites
- trochophores in Nemertea
- closed circulatory using coelom vs. lacking a circulatory system
- has a complete digestive system (anus) vs. incomplete (no anus)
- mouth attached proboscis vs. gut attached proboscis
what orders are within Enopla?
Heteronemertea and Paleonemertea
what orders are within Anopla?
Bdellonemertea and Hoplonemertea
where are the coeloms in Nemerteans and what function do they serve?
- form coelomic tubes
- acts as a circulatory system
how do Nemertean proboscis differ to Platyhelminths’ proboscis?
Nemertean = connected to mouth
Platyhelminths = connected to gut
what key difference between stylet formation and Annelid chaetae formation?
- stylets formed intracellularly and are limited in size
- chaetae formed extracellularly
