invertebrates pt 4 (annelida -> nematoda)

phylum annelida include the ______ _____. they are found in marine, freshwater, and terrestrial habitats

segmented worms

(annelida means “little rings”)

what are the 3 classes of phylum annelida?

1) oligiochaeta

→ earthworms

2) polychaeta

→ marine worms (like deep sea vent tube worms, christmas tree worms, clam worms)

3) hirundinea

→ leeches

class oligiochaeta belongs to what phylum? what are some unique characteristics?

phylum annelida

→ the earthworms: they are important for mixing soil and moisturizing soil using mucus from their body

they are hermaphrodites but they cross-fertilize → they can lay twice as many eggs because of this

class polychaeta belongs to what phylum? what are some unique characteristics?

phylum annelida

→ the marine worms

they have parapoda (feet) which are for locomotion and gas exchange

class hirudinea belongs to what phylum? what are some unique characteristics?

phylum annelida

→ the leeches

some are parasitic with blade-like jaws to slit the skin and feed on blood

they produce an anesthetic so you don’t know where they’ve attached

they produce hirudin, a chemical that prevents the blood from clotting

how can leeches from class hirudinea be used for medicinal purposes?

used as an anti-coagulant !!

draining blood that accumulates following injury or surgery !!

which class of annelida produces hirudin, a chemical that prevents blood from clotting, and an anesthetic so you don’t know where they’ve attached to suck blood?

class hirudinea

which class of annelida has feet called parapoda for locomotion and gas exchange?

class polychaeta

which class of annelida are hermaphrodites and can cross-fertilize with other worms?

class oligiochaeta

phylum nematoda contains the _____ _____

round worms

→ these are NON-SEGMENTED worms

THEY ARE NOT THE SAME AS THE SEGMENTED WORMS

where is phylum nematoda found?

marine, freshwater, terrestrial, living on plants, living in the body fluids of animals

→ everywhere 🚬

what is a unique feature of phylum nematoda?

their body is covered by a cuticle (tough outer coat) for protection

what are nematodes important for?

they are good decomposers and responsible for cycling nutrients

*others are parasitic to animals and plants

phylum nematoda are ____________, meaning they have a false body cavity where the mesoderm does not fully line the coelom

pseudocoelomates

phylum nematoda contains a round worm that causes trichinosis. it infects humans when they eat undercooked pork. what is the name of this round worm? what unique feature does it have?

Trichinella spiralis

this worm creates a fucking cyst around itself inside the uncooked meat in the muscle and is then eaten by a human host

which phylum is responsible for the worm Trichinella spiralis, that causes trichinosis when humans eat undercooked pork?

phylum nematoda