Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.

By signing up, I agree to StudyStack's Terms of Service and Privacy Policy.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.

Remove ads
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Zoology Ch. 9

Zoology Ch. 9 Vocabulary Review

A hypothesis formulated to explain the origin of multicellularity from protis ancestors. Animals may have been derived when protists associated and cells became specialized and interdependen. Colonial Hypothesis
The idea that multicellular organisms could have arisen by the formation of plasma membranes within a large, multinucleaste protists. Syncytial Hypothesis
Thin, flat cell covering the outher surface, and some of the inner surface of poriferans. Pinacocytes
Tubular cells in sponge body wall that create a water channel to an interior chamber. Porocytes
A jellylike layer between the outer and inner layers of a sponge. Contains wandering amoeboid cells. Mesohyl
Amoeboid cells within the mesohyl of a sponge. Mesenchyme cells are specialized for reproduction, secreting skeletal elements, transporting food, storing food, and forming contractile rings around openings in the sponge wall. Mesenchyme cells
Cells of sponges that create water currents and filter food. Choanocytes
Skeletal elements that some mesenchyme cells of a sponge body wall secrete. May be made of calcum carbonate or silica. Spicules
A fibrous protein that makes up the supportive framework of some sponges. Spongin
The simplest of the three sponge body forms. These sponges are vaselike, with choanocytes directly lining the spongocoel. Ascon
A sponge body form characterized by choanocytes lining radial canals. Sycon
The sponge body form that has an extensively branched canal system. The canals lead to chambers line by choanocytes. Leucon
The immature stage of the sponge in which the adults and immatures are different in body form and habitat. Larva
Resitstant, overwintering capsule formed by freshwater, and some marine, sponges that contains masses of mesenchyme cells. Amoeboid mesenchyme cells are released and organize into a sponge. Gemmules
A sheet of cells covering the surface of an animal's body. Epidermis
The endodermally derived lining of the gastrovascular cavity of Cnidaria. Gastrodermis
A gel-like matrixs between the epidermis and gastrodermis of cnidarians. Mesoglea
An organelle charactristic of the cnidaria that is used in defense, food gathering, and attachment. Cnida
The cells that produce and discharge the cnidea in members of the phylum Cnidaria. Cnidocytes
A cnidarian cnida usually armed with spines or barbs and containing a venom that is injected into a prey's flesh. Nematocysts
Usually, the sexual stage in the life cycle of cnidarians. The jellyfish body form. Medusa
The attached, usually asexual, stage of cnidarian. Polyp
The use of body cavity fluids, confined by the body wall, to give support. Hydrostatic Skeleton
A ciliated free swimming larva of most cnidarians. This develops following sexual reproduction and metamorphoses into a polyp. Planula
A feeding polyp in a colonial hydrozoan. Gastrozooid
A polyp of a hydrozoan cnidarian that produces medusea. Gonozooid
A structure that hangs from the oral surface of a cnidarian medusa and surrounds the mouth. Manubrium
An organ of equilibrium and balance in many invertebrates. They usually consist of a fluid-filled cavity containing sensory hairs and a mineral mass called a statolith. Statocyst
A sensory structure at the margin of the scyphozoan medusa. It consists of a staocyst and a photoreceptor. Rhopalium
The polyp stage of a scyphozoan. Scyphistoma
Miniature medusa produced by asexual budding of a scyphistoma. They develop into sexually mature medusa. Ephyrae
The condition in a hermaphrodite in which male gonads mature before female gametes. Prevents self fertilization. Protandry
Rows of cilia that are the locomotor organs of ctenophorns. Comb Rows
Adhesive cells on ctenophoran tentacles for capturing prey. Colloblasts
Created by: rburrier