Sea stars breath through their skin gills and tubed feet to preform gas exchange.
seastars, or starfish may be poisonous
eggs
Gas exchange is a function of respiration not digestion.
Seastars are invertebrates.
they move by the bottom of their arms
Alveoli is where gas exchange occurs.
squid and seastars
The exchange surfaces are moist.
gaseous exchange
gas exchange occurs between the thin walls of the alveoli and the thin walls of the capillaries
worms carry out gas exchange by absorbing air through their skin
The actual sites of gas exchange within the lungs are the alvioli.