Plume
This soft, bright-red structure serves the same purpose
as a mouth would if the tubeworm had one. It sucks in
the ingredients that the microbes living in the
worm's body will use to fashion its food. These three
ingredients—oxygen and carbon dioxide in seawater
and hydrogen sulfide in the superheated water erupting
from the vent or black smoker—tend to react
violently when they come into contact with each other.
Yet using special hemoglobins in its blood-rich plume
(hence the red color), the tubeworm has found a way to
transport the ingredients in its blood without this
reaction taking place—and without the toxic
hydrogen sulfide poisoning it, as it would you or me.
