invertebrates
animal without a backbone
gills
organs that remove oxygen from water
mantle
thin layer of soft tissue that covers the internal organs and produces the shell
open circulatory system
system in which the blood is not always contained in blood vessels
herbivore
animal that only eats plants
carnivore
animal that only eats other animals
scavenger
an organism that feeds on dead or decaying material
omnivore
animal that eats both plants and animals
radula
flexible ribbon of tiny teeth used to obtain food
gastropod
largest group of mollusks; having one or no shell; includes snails and slugs
bivalve
mollusk having two shells held together by hinges and strong muscles
cephalopod
ocean dwelling mollusk whose foot is adapted to form arms & tentacles around the mouth
closed circulatory system
system in which the blood is always contained in blood vessels
broad foot
organ that gastropods & bivlalves use for crawling, digging, or attaching to a surface
arms
modified foot of a cephalopod; covered with suckers on the underside; used to move, bring food to the mouth, or "taste" surrounding water
tentacles
modified foot of a cephalopod with suckers on the tips; used to grab food during hunting
filter feeder
organisms that feed by straining tiny organisms and plant matter out of the water
cilia
tiny projections on the gills that move muscus coated food from the gills to the palps
palps
organ that moves mucus covered food from the cilia to the mouth
bilateral symmetry
two halves that are mirror images of each other
one way digestive tract
digestive system in which food enters through one opening, passes through the body, and waste exits through another opening
snail
gastropod with one shell and a broad foot
slug
gastropod with no shell and broad foot
shell
hard covering of a mollusks that protects the internal organ
anus
orifice through which food waste exits the body
mantle cavity
space inside the mantle where the internal organs are located
umbo
oldest part of the shell of a bivalve from which the shell grows
ligament
part of a bivalve that opens the shells when the adductor muscle is relaxed
intestine
organ that completes digestion and absorbs nutrients from food
heart
organ that pumps blood
adductor muscles
muscles of a bivalve that keep the shell tightly closed
exhalant siphon
tube through which a bivalve expels water from which it has removed food and oxygen
inhalant siphon
tube through which a bivlave takes in water to filter out food and get oxygen
stomach
organ that breaks down food with digestive juices
mucus
slimy substance created by some gastropods to aid in creeping on surfaces to protect the foot OR sticky substance on gills of a bivalve to capture food as it filters through the gills
larva
immature form of an invertabrate animal that does not look like the adult
oyster
marine bivalve often farmed for its pearl-making ability
pearl
a smooth, rounded bead formed within the shells of certain mollusks in response to an irritant
pearl sac
piece of mantle tissue that surrounds an irritant to form the center of a pearl
nacre
also called mother of pearl; material that makes a pearl oyster's shell as well as forms the pearl
squid
cephalopod with an internal shell and a modified foot that forms 8 arms and 2 tentacles
octopus
cephalopod with no shell and a modified foot that forms 8 arms and no tentacles
nautilus
cephalopod with an external shell and a modified foot that forms many arms
ink sac
organ in a cephalopod that produces ink ejected from the body to confuse and distract predators
gill hearts
pump blood from the body back to the gills to get oxygenated
liver
organ that helps remove toxins from the blood
beak
hard, sharp, tooth-like structures used by cephalopods to crush and kill prey
suckers
structures on the underside of the arms of octopi & squid used for grabbing and pulling
jet propulsion
the means by which squid & octopi propel themselves quickly through the water; movement of the body caused by the forced expulsion of water
camouflage
change of appearance to blend with surroundings to hide from predators
predator
organism that exists by preying on other organisms
prey
an animal hunted or seized for food
mantle collar
structure through which a cephalopod allows water to enter the mantle cavity in preparation for jet propulsion