Chapter 33

Question 1

The major group of parazoans is phylum ____ the sponges

Answer 1

Porifera

Question 2

Adult sponges are ____ they are anchored to a surface for their entire lives

Answer 2

sessile

Question 3

lacking head or appendages, mouth or anus, and the organized internal structure characteristic to all other animals

Answer 3

sponges

Question 4

A unique feature of sponge cells is their ability to ____

Answer 4

differentiate and dedifferentiate from one type to another

Question 5

Facing the internal cavity of sponges are cells called ____

Answer 5

choanocytes

Question 6

The large sponge openings are known as an ____through which water is expelled

Answer 6

osculum

Question 7

Between the outer and inner layer of cells sponges consist mainly of a gelatinous, protein-rich matrix called the ___

Answer 7

mesohyl

Question 8

Sponge needles made of calcium carbonate or silica

Answer 8

spicules

Question 9

Some sponge cells secrete fibers of a tough protein called ____

Answer 9

spongin

Question 10

What are the three classes of sponges

Answer 10

Hexactinellida, Demospongiae, and Calcarea

Question 11

The embryonic endoderm eventually forms the

Answer 11

digestive tissue/gastrodermis

Question 12

The embryonic mesoderm eventually forms the

Answer 12

muscles

Question 13

All Cnidarians are ___

Answer 13

carnivores

Question 14

Diploblastic
Radially symmetrical
no organs
no brains

Answer 14

Cnidarians

Question 15

Cylindrical Cnidarian

MOuth surrounded y tentacle at the end of the cylinder opposite where it is attached

Answer 15

Polyp

Question 16

Discoidal or umbrella shaped Cnidarian
mouth surrounded by tentacles on one side
most live in free water

Answer 16

Medusa

Question 17

The cnidarian body plan contains what three layers

Answer 17

Epidermis (tissue)
Mesoglea
Gastrodermis (tissue)

Question 18

The hydrostatic skeleton of Cnidarians provides a ___ and give the animal ____

Answer 18

rigid structure against which muscles can operate

shape

Question 19

In addition to the hydrostatic skeleton of all polyps some build an exoskeleton composed of ___ or ____

Answer 19

chitin

calcium carbonate

Question 20

microscopic stinging capsules

Answer 20

nematocysts

Question 21

What are the five classes of Cnidarians

Answer 21

Anthozoa
Hydrozoa
Scyphozoa
Cubozoa

Question 22

Largest class of Cnidaria
Consists of solitary and colonial polyps
Include sea anemones and stony corals

Answer 22

Class Anthozoa

Phylum Cnidarian

Question 23

Medusae of this class include the box jellyfish
Some have image forming eyes
Sting of some is fatal to humans

Answer 23

Class Cubozoa

Phylum Cnidaria

Question 24

Most have a medusa and polyp form 
Polyp stage of most is colonial
Includes the Portuguese Man of War 
Includes the Hydra 
The only class with freshwater members

Answer 24

Class Hydrozoa

Phylum Cnidaria

Question 25

Includes the true jellyfish | Medusa form is much more conspicuous than the polyp

Answer 25

Class Scyphozoa

Question 26

Includes the star jellies | Resembles a medusa in most ways but is attached to a substrate

Answer 26

Class Staurozoa