Create an account
what is on the ventral surface
covered with cilia (traction) and mucas cells (traction/capture prey)
What are the parts of the nervous system
ganglia,longitudinal nerves, transverse nerves, peripheral nerves
what are the parts of the muscular system
longitudinal muscles, circular muscles, diagonal muscles and parenchymal muscles
describethe excretory system
runs through mesoderm, many tubes, run from anterior to posterior, from these pores open to dorsal surface, smaller tubules branch off and end with a "flame cell"
what are the steps of ingestion
capturing prey, break prey into smaller pieces, pharynx sucks bits of food into intestine
how do they capture prey
slime cells on ventral surface secrete mucas which gets sprayed onto prey to immobilize them
how do they break prey into smaller pieces
gland cells inside intestine secrete digestive enzymes which get sprayed onto prey (partially digests it)
Describe intestine structure
3 branches, 1 anterior 2 posterior, these further branch into smaller tubes which increase surface area for digestion and absorbtion of food
how does digestion work
gland cells in the intestine secrete digestive enzymes, nutritive cells have flagella which mix the food/enzymes, nutritive cells then engulf food and finish digestion inside vacules, food then difuses to all parts of the planaria
how does elimination work
pharynx extends, animal sucks in water to fill the intestine, once filled the muscles contract to force contents back out of pharynx
how does asexual reproduction work
regeneration- worm constricts into middle and pulls apart, each piece will develop new halves
how does sexual reproduction work
1- exchange sperm through the genital pore
2- sperm goes to the copulatory sac to mature
3- once mature, the sperm traves through oviducts towards eggs
4- zygote then travels back towards genital chamber, along the way yolk (food) and capsule is added
5- encapsulated zygote released into water to eventually hatch in 2-3 weeks
what are the barriers parasites have to overcome
1- reaching and penetrating new hosts
2-surviving against defenses of host (white blood cells)
what adaptations have parasites used to overcome
1- structures for attachment (flukes have suckers, tapeworms have suckers, hooks and teeth)
2-resistant outer body coverings (tapeworms have cuticles)
3- complex reproductive systems (tapeworms have reproductive organs in each of their body segments, can self fertilize)
4- intricate reproductive cycles (flukes usea variety of intermediate hosts to reach primary host, snail to fish to human, hard to get rid of)
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together