Module #11

Question 1

invertebrates

Answer 1

animals that lack a backbone

Question 2

vertebrates

Answer 2

animals that posses a backbone

Question 3

spherical symmetry

Answer 3

an organism possesses spherical symmetry if it can be cut into two identical halves by any cut that runs through the organisms center

Question 4

radial symmetry

Answer 4

an organism possesses radial symmetry if it can be cut into two identical halves by any longitudinal cut through its center

Question 5

bilateral symmetry

Answer 5

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

Question 6

collar cells

Answer 6

flagellated cells that push water through a sponge

Question 7

amoebocytes

Answer 7

cells that move using pseudopds and perform different functions in different animals

Question 8

gemmule

Answer 8

a cluster of cells encased in a hard, spicule- reinforced shell

Question 9

polyp

Answer 9

the sessile tubular for of a cnidarian with a mouth and tentacles at one end and a basal disk at the other

Question 10

medusa

Answer 10

a free swimming cnidarian with a bell shaped body and tentacles

Question 11

epithelium

Answer 11

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

Question 12

mesoglea

Answer 12

the jellylike substance that separates the epithelial cells in a cnidarian

Question 13

nematocysts

Answer 13

small capsules that contain a toxin which is injected into prey or predators

Question 14

testes

Answer 14

organs that produce sperm

Question 15

ovaries

Answer 15

organs that produce eggs

Question 16

anterior end

Answer 16

the end of an animal that contains its head

Question 17

posterior end

Answer 17

the end of an animal that contains its tail

Question 18

circulatory system

Answer 18

a system designed to transport food and other necessary substances throughout a creatures body

Question 19

nervous system

Answer 19

a system of sensitive cells that respond to stimuli such as sound, touch, and taste

Question 20

hermaphroditic

Answer 20

possessing both the male and the female reproductive organs

Question 21

mantle

Answer 21

a sheath of tissue that encloses the vital organs of a mollusk makes the mollusk shell and performs repiration

Question 22

shell

Answer 22

a tough multilayered structure secreted by the mantle generally used for protection but sometimes for body support

Question 23

visceral hump

Answer 23

a hump that contains a mollusks heart digestive and excretory organs

Question 24

foot

Answer 24

a muscular organ that is used for locomotion and takes a variety of forms depending on the animal

Question 25

radula

Answer 25

n organ covered with teeth that mollusks use to scrape food into their mouths

Question 26

univalve

Answer 26

an organism with a single shell

Question 27

bivalve

Answer 27

an organisms with two shells