Animals that lack a backbone
Animals that possess a backbone
An organism possesses spherical symmetry if it can be cut into two identical halves by any cut that runs through the organism's center
An organism possesses radial symmetry if it can be cut into two identical halves by any longitudinal cut through its center
An organism possesses bilateral symmetry if it can only be cut into two identical halves by a single longitudinal cut along its center which divides it into right and left halves
An outer layer of cells designed to provide protection
The jellylike substance that separates the epidermis from the inner cells in a sponge
Flagellated cells that push water through a sponge
Cells that move using pseudopods and perform different functions in different animals
A cluster of cells encased in a hard, spicule-reinforced shell
The sessile, tubular form of a cnidarian with a mouth and tentacles at one end and a basal disk at the other
A free-swimming cnidarian with a bell-shaped body and tentacles
Animal tissue consisting of one or more layers of cells that have only one free surface, because the other surface adheres to a membrane or other substance
The jellylike substance that separates the epithelial cells in a cnidarian
Small capsules that contain a toxin which is injected into prey or predators
Organs that produce sperm
Organs that produce eggs
The end of an animal that contains its head
The end of an animal that contains its tail
A system designed to transport food and other necessary substances throughout a creature's body
A system of sensitive cells that respond to stimuli such as sound, touch, and taste
Masses of nerve cell bodies
Ganglia (singular: ganglion)
Possessing both the male and the female reproductive organs
The ability to regrow a missing part of the body
A sheath of tissue that encloses the vital organs of a mollusk, makes the mollusk's shell, and performs respiration
A tough, multilayered structure secreted by the mantle, generally used for protection, but sometimes for body support
A hump that contains a mollusk's heart, digestive, and excretory organs
A muscular organ that is used for locomotion and takes a variety of forms depending on the animal
An organ covered with teeth that mollusks use to scrape food into their mouths
An organism with a single shell
An organism with two shells
Please allow access to your computer’s microphone to use Voice Recording.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!
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.
Your microphone is muted
For help fixing this issue, see this FAQ.