Section 20.4- Crustaceans: Aquatic Arthropods

Question 1

aquatic arthropods that range in size from woodlice to giant crabs

Answer 1

crustaceans

Question 2

strengthens the crustaceans crusty exoskeleton

Answer 2

calcium carbonate

Question 3

crustaceans that people often call crawfish or crawdads

Answer 3

crayfish

Question 4

two major regions of the crayfish

Answer 4

cephalothorax
abdomen

Question 5

an especially hard outer shell that provides the vital organs with added protection from predators

Answer 5

carapace

Question 6

a forward extension of the carapace the protects the well-defined head

Answer 6

rostrum

Question 7

two _____________eyes are attached to the head by flexible stalks

Answer 7

compound

Question 8

the shorter feelers attached to a crayfish’s head

Answer 8

antennules

Question 9

the sense of touch, taste, and smell come from the large

Answer 9

antennae

Question 10

the chewing appendages located near the opening of the mouth

Answer 10

mandibles and maxillae

Question 11

set of appendages designed to help crayfish keep a firm grip on its food

jaw feet

Answer 11

maxillipeds

Question 12

a large pair of appendages with pincers which the crayfish uses to seize its prey and for self-defense

Answer 12

chelipeds

Question 13

the crayfish’s abdominal appendages are known as

Answer 13

swimmerets

Question 14

formed by the swimmerets on the sixth segment

used for swimming

Answer 14

uropod

Question 15

flat triangular projection terminating the sixth segment

Answer 15

telson

Question 16

serves as a gizzard, grinding food into small particles for digestion

Answer 16

gastric mill

Question 17

crayfish breathe through

Answer 17

gills

Question 18

crayfish have an ____________ circulatory system

Answer 18

open

Question 19

an open area surrounding the heart in which collects before it reenters the heart through the ostia

Answer 19

pericardial sinus

Question 20

special excretory glands which lie in front of the stomach and open to the outside near the base of the antennae

functions like a kidney to remove wastes from the blood

Answer 20

green glands

Question 21

located at the base of the antennules and contain sensory hairs and grains of sand

enables crayfish to adjust position and maintain equilibrium

Answer 21

statocysts

Question 22

most crustaceans are

Answer 22

small or microscopic

Question 23

crustacean that rolls into a ball whenever it is disturbed

often called sowbug, pillbug, or roly-polys

Answer 23

woodlouse

Question 24

found in salt lakes and marshes and are commonly used as living food in aquariums

Answer 24

brine shrimps

Question 25

marine crustaceans that attach themselves to rocks etc

Answer 25

barnacles

Question 26

some of the most familiar of the extinct arthropods small aquatic arthropods similar in some ways to horseshoe crabs

Answer 26

trilobites

Question 27

one of the most bizarre arthropods that has become extinct was

Answer 27

Anomalocaris