Lab 4

Question 1

Which appendages replace jaws in Chelicerates?

Answer 1

Chelicerae

Question 2

How many pairs of antennae do Myriapods have?

Answer 2

1 pair

Question 3

What subphylum do horseshoe crabs belong to?

Answer 3

Chelicerata

Question 4

How many pairs of walking legs do organisms from Subphylum Hexapoda have?

Answer 4

3 pairs

Question 5

What is the exoskeleton of the horseshoe crab made from?

Answer 5

Chitin

Question 6

Name the tagmata found in organisms belonging to subphylum Myriapoda.

Answer 6

Head and trunk

Question 7

Name the tagmata found in organisms belonging to subphylum Crustacea.

Answer 7

Cephalothorax and abdomen

Question 8

Name the two chambers of the stomach of crayfish.

Answer 8

Cardiac and pyloric

Question 9

Name the tagmata found in organisms from subphylum Hexapoda.

Answer 9

Head, thorax, abdomen

Question 10

What is the role of tympana?

Answer 10

Act like ear drums and are used for hearing.

Question 11

What is the role of the gill bailer?

Answer 11

Used to draw water (and thus oxygen) through the gill chambers.

Question 12

What is the role of the telson in the horseshoe crab?

Answer 12

Anchoring and ploughing in the sand, and righting the animal when it flips over.

Question 13

What is the role of the pedipalps in the male horseshoe crab?

Answer 13

Pedipalps are enlarged into claspers, used to hold onto the female as she carries him out of the water and onto the shore to reproduce.

Question 14

What is the role of spinnerets?

Answer 14

Produces silk used for making webs, warpping prey, and encasing eggs

Question 15

What is the role of pleopods?

Answer 15

Transfer sperm from male genital opening to the female.

AKA copulatory swimmerets.

Question 16

Name 3 different appendages found in the cephalothorax of the crayfish.

Answer 16

• Carapace
• Rostrum
• Chelipeds

Question 17

Name 2 specimen from today’s lab that have a telson.

Answer 17

Horseshoe crab and Crayfish.

Question 18

Name a specimen from today’s lab that has book lungs.

Answer 18

Garden spider.

Question 19

Define tagmata.

Answer 19

Reduction and fusion of metameres into distinct functional body units.

Question 20

Name 2 characteristics that generally make spiders sexually dimorphic.

Answer 20

• Males are much smaller than females

- Pedipalps are modified to transfer sperm into the female epigyne