worms Flashcards
how does phylum nemertea capture prey?
they fire a proboscis to entangle the prey, that is why they are called shooter worms or ribbon worms
what is the meso derm of phylum nematoda
pseudocoelomatte, a body cavity covered only on one side with mesocells
what is a new innovation of the nemadtoda?
the cuticle, a non living external layer excreted by the underlying epidermis. this limits growth so the animal must shed its outer layer constantly, but it provides protection from the environment and it contains high hydrostatic pressure. they also do not have circular muscles.
how is the hypodermis used in locomotion in nematoda?
the flexible cuticle takes over the antagonistic function of the circular muscle, like the skeleton of a hydropora medusa. the hydrostatic skeleton of the nematoda has a very high internal hydrostatic pressure
what is unusual charatteristic of the nematode muscle system?
the longitudinal muscles are connected to the nerve cord
what are some charatteristics of the phylum annelida?
they are eucoelomate, both side of coelom are lined with mesocells.
they developed metamerism, a segmented body.
and they have a true coelom formed through schizocoely.
they have a true gut and a complete digestive and complex nervous system.
what is the taxonomy of the annelida?
what are the two amin groups of annilida?
errantia and sedentari, based on whetear they are sessile or free moving.
errantia are free living clear headed predatory species wich has tentacles or jaws to catch prey
what is a schematic of the bodyplan of the annelidae?
thin cuticle, epidermis, circular muscle
sedentaria usually lives in tunnel and rely on tentacles for catching preys
explain the respiratory system of the annelida.
what are the giant axons used for in the annelida’s nervous system?
how does locomotion happens in annelida? in what forms?
