Mollusca general characteristics Flashcards
Where do molluscs live
mainly marine, some freshwater, many terrestrial
what type of symmetry do they have
bilateral
How many tissue layers
three (triploblastic)
Celomate definition
true body cavity
Describe celome in molluscs
reduced and limited to the region around heart
Three main parts of body plan
muscular foot
visceral mass
mantle
describe fuction of foot
locomotion
what is the visceral mass
contains most of the internal organs
describe the manthe
heavy folds of tissue that keeps everything together
describe the reproduction
some are monoecious but most dioecious
broadcast fertilization if live in water
trocophae=ciliated larvae
where are the gonads located
in visceral mass
describe the nervous system
consists of several ganglia connected by nerve cords
open or closed circulatory system
most have open
describe how the open circulatory system works
“heart” pumps hemolymph through vessels into hemoceel.
blood then diffuses back into the heart and is pumped out to the body again
what is the hemoceel
open sinus space
