Biology Lab

Front 1

crayfish are in what phylum?

Back 1

anthropoda

Front 2

what class is the crayfish in?

Back 2

crustacea

Front 3

crayfish are what kind of eaters?

Back 3

master scavengers; they eat dead or living animals and plants, including fish, tadpoles, worms, insects,and plants.

Front 4

how long is a crayfish usually?

Back 4

5 inches or more

Front 5

what habitat do they live in?

Back 5

in freshwater, swamps or rivers. they make their homes by burrowing into muddy banks and bottoms.

Front 6

external anatomy

Back 6

dorsal surface and ventral surface

Front 7

dorsal surface

Back 7

cephalothorax, carapace, rostrum, stalked compound eye, antennules, and antennae

Front 8

ventral surface

Back 8

mouth, maxillipeds, cheliped, walking appendages

Front 9

cephalothorax

Back 9

in crayfish, the head and thorax are fused into a single part called a cephalothorax

Front 10

carapace

Back 10

the hard covering of the cephalothorax; it is v shaped

Front 11

rostrum

Back 11

the anterior end of the cephalothorax. looks like a helmet

Front 12

stalked compound eye

Back 12

one on each side of the rostrum

Front 13

antennules

Back 13

also at end of rostrum, these short appendages have small sacs at their base which contain the hearing and balance organs

Front 14

antennae

Back 14

these very long appendages at the end of the rostrum are sense organs for taste and touch

Front 15

mouth

Back 15

has 2 parts; mandibles and maxillae

Front 16

mandibles

Back 16

triangle shaped with little teeth on inner edges, 1 pair

Front 17

maxillae

Back 17

2 pairs. the larger pair moves water into the gill chamber. the smaller pair moves food into the mouth opening.

Front 18

maxillipeds

Back 18

3 pairs, increasing in size from front to rear. hold food and also function in the touch and taste senses

Front 19

cheliped

Back 19

look like giant pincers. these are used to grasp and tear food and for defense

Front 20

walking appendages

Back 20

legs with 7 joints in each one. can move forward, sideways, and backwards. 4 pairs of these

Front 21

how many segmants are in the abdomen?

Back 21

6

Front 22

swimmerets

Back 22

each segment has a pair; they are used to pick and clean debris and parasites off the crayfish

Front 23

telson

Back 23

central section of the tail

Front 24

uropod

Back 24

on either side of the telson

Front 25

respiratiory system

Back 25

composed of gills which are attached to legs takes oxygen from the water and passes it along to the blood

Front 26

digestive system

Back 26

1 month 2 esophagus 3 stomach 4 digestive glands 5 intestine and 6 anus

Front 27

gastric mill

Back 27

little teeth inside the stomach

Front 28

excretory stystem

Back 28

glands called green glands function in this capacity in the crayfish. they are located anterior to the esophagus and below the compound eye

Front 29

circulatory system

Back 29

1 heart 2 abdominal aorta 3 anterior dorsal aorta

Front 30

nervous system

Back 30

brain and ventral chord