Echinoderm

Question 1

a marine invertebrate of the phylum Echinodermata, such as a starfish, sea urchin, or sea cucumber.

Answer 1

echinoderm

Question 2

an internal skeleton, such as the bony or cartilaginous skeleton of vertebrates

Answer 2

endoskeleton

Question 3

a defensive organ like a minute pincer present in large numbers on an echinoderm.

Answer 3

Pedicellariae

Question 4

a perforated plate by which the entry of seawater into the vascular system of an echinoderm is controlled

Answer 4

Madreporite

Question 5

one of the numerous minute canals lined with choanocytes which radiate from the paragastric cavity in some sponges and end just below the surface of the sponge

Answer 5

Radial canal

Question 6

the circular water tube that surrounds the esophagus of echinoderms

Answer 6

Ring canal

Question 7

a thing comparable to an arm in form or function, typically something that projects from a larger structure

Answer 7

Arm/Ray

Question 8

symmetry around a central axis, as in a starfish or a tulip flower

Answer 8

Radial Symmetry

Question 9

a network of water vessels in the body, the tube feet being operated by hydraulic pressure within the vessels

Answer 9

Water Vascular System

Question 10

extends from the mouth to the end of each ray or arm

Answer 10

Amburacral Groove

Question 11

a small piece of calcified material forming part of the skeleton of an invertebrate animal such as an echinoderm

Answer 11

Ossicles

Question 12

one of the tubular pouches opening into the alimentary canal in the pyloric region of most fishes

Answer 12

Pyloric Caecum

Question 13

connects the stomach to the duodenum

Answer 13

Pyloric Stomach

Question 14

the left margin joins the greater curvature at an acute angle

Answer 14

Cardiac Stomach

Question 15

a cavity, or the dilated end of a duct

Answer 15

Ampullae

Question 16

an organ that produces gametes; a testis or ovary

Answer 16

Gonads

Question 17

having the body radially arranged, usually in the form of a star, with five or more rays or arms radiating from a central disk

Answer 17

Central Disc

Question 18

each of a large number of small, flexible, hollow appendages protruding through the ambulacra, used either for locomotion or for collecting food and operated by hydraulic pressure within the water-vascular system

Answer 18

Tube Feet

Question 19

is a male organism’s sperm fertilizing a female organism’s egg outside of the female’s body

Answer 19

External Fertilization

Question 20

the formation of new animal or plant tissue

Answer 20

Regeneration

Question 21

a relative of the starfish

Answer 21

Sea star

Question 22

ophiuroids are echinoderms in the class Ophiuroidea closely related to starfish. They crawl across the sea floor using their flexible arms for locomotion

Answer 22

Brittle star

Question 23

a marine echinoderm that has a spherical or flattened shell covered in mobile spines, with a mouth on the underside and calcareous jaws

Answer 23

Sea urchin

Question 24

flattened sea urchin that lives partly buried in sand, feeding on detritus

Answer 24

Sand dollar

Question 25

a sedentary marine echinoderm that has a small body on a long jointed stalk, with featherlike arms to trap food.

Answer 25

Sea lilies

Question 26

an echinoderm with a small disklike body, long feathery arms for feeding and movement, and short appendages for grasping the surface.

Answer 26

Feather stars

Question 27

an echinoderm that has a thick, wormlike body with tentacles around the mouth. They typically have rows of tube feet along the body and breathe by means of a respiratory tree

Answer 27

Sea cucumbers

Question 28

have no arms, but the circle is rimmed with flat spines that look like daisy petals. The upper surface of the animal is delicately plated

Answer 28

Sea daisies

Question 29

the property of being divisible into symmetrical halves on either side of a unique plane.

Answer 29

bilateral symmetry