nematoda Flashcards
what kind of symmetry
bilateral
what kind of body plan
tube within a tube
what level of organization
organ level
what do they have to excrete
excretory pores
describe their outer wall
non-segmented: smooth
what do they do for respiration
diffusion
what kind of digestive tract
complete: mouth and anus
what kind of coelom? describe advantages, what it provides
psuedocoelom (fluid filled)
- body cav incompletely lined with mesoderm
- Provides space for development of organs
- circulatory system: easy passage of molecules
- Hydrostatic skeleton
do most have separate sexes?
yes
fertilization is _____
internal
how many germ layers
three
in species ascaris, which sex is larger
females
what kind of motion used to move and why
whiplike motion: due to only having longitudinal muscles
life will begin when…
larvae within a protective covering are swallowed
describe the journey of a roundworm in a host
- Escape through the covering, burrow through the host’s intestinal wall
- Through the organs: Intestine, liver, 💕, lungs
- Up the windpipe to be swallowed to intestine
- Produces larva-containing eggs, out with feces
trichinosis can be caused by..
eating rare pork with encysted larvae
how do trichinella encyst in skeletal muscles?
burrows into wall of small intestine, producing live offspring, carried by blood stream
filarial worms cause elephantiasis. describe how they infect
uses mosquito as secondary host. biting transports larvae.
adult worms reside in lymphatic vessels. fluid return is delayed, limbs swell, resembling an elephant
name how to prevent a pinworm or hookworm (feed on blood in intestinal wall) infection that is common in children
good hygiene, proper disposal of sewage, cooking meat thoroughly
