Test 1

Question 1

Arthropoda Characteristics

Answer 1

• Bilateral symmetry
• Chitinous exoskeleton
• Segmented body
• Jointed appendages
• Hemocoel, not coelom
• No cilia
• Ventral nerve cord with dorsal brain

Question 2

Arthropoda is comprised of 3 or 4 subphyla

Answer 2

•	Trilobite – extinct (known by fossils)
•	Chelicerata
•	Crustae
•	Atelocerata 
*crustae + atelocerata = mandibuata*

Question 3

Tagmosis

Answer 3

grouping of body segments to form functional units

Question 4

Head + Trunk

Answer 4

Milipedes and Centipedes

Question 5

Cephalothorax + abdomen

Answer 5

Arachnids and Crustaceans

Question 6

• Head + thorax + abdomen

Answer 6

Insects

Question 7

Insect Body

Answer 7

• Head – 3 fused segments
• Thorax – 3 fused segments; primarily for locomotion
• Abdomen – reproduction and digestion

Question 8

Exoskeleton layers

Answer 8

• Epicuticle
• Exocuticle
• Endocuticle
• Epidermis - only layer with living cells

Question 9

Exoskelton structures

Answer 9

Pore Canal
Seta
Apodeme
Sulcus

Question 10

Pore Canal

Answer 10

moves substances from the living cells in epidermis to exterior through non living layers

Question 11

seta

Answer 11

“hair-like” projections that can be porous for chemical uptake or sensory function

Question 12

Apopdeme

Answer 12

inward projections where muscle attaches

Question 13

Sulcus

Answer 13

a groove on the exterior that correlates with the apodeme

Question 14

Chitin

Answer 14

a nitrogenous polysaccharide
• Fibrils run in parallel to form sheets
• Sheets turned so layers run in different directions
• This adds strength

Question 15

Sclerotization

Answer 15

irreversible process strengthens exocuticle by crosslinking layers

Question 16

Soft Cuticle

Answer 16

arthrodial memebrane that lacks exocuticle
• Important for bloodfeeding
• Gravid females and repletes

Question 17

Four basic types of protuberances or extensions of cuticle:

Answer 17

• Multicellular spine
• Seta
• Acanthae
• Microtrichia

Question 18

Exoskeleton advantages and disadvantages

Answer 18

•	Resists chemicals and pathogens
•	Resists water loss or gain
•	Protects from mechanical damage
•	Provides good leverage for muscles  
•	Used for camouflage and waste storage
But...
•	Restrict growth (molt required)
•	Limits maximum size

Question 19

Size Matters

Answer 19

surface to volume ratio

Question 20

Arachnids

Answer 20

lack antennae, 8 legs, cephalothorax + abdomen, carnivores
•	Araneae
•	Opiliones
•	Acari
•	Pseudoscorpiones
•	Scorpions

Question 21

Crustaceans

Answer 21

branched appendages, calcified exoskeleton (much harder), mandibuletes, biramous appendages, 2 sets of antennae, also two pair of maxillae

Question 22

Crustaceans - Order

Answer 22

Isopoda - Pill Bugs

Question 23

Myriapod

Answer 23

• Chilopoda – centipedes
o 1 pair of legs per segment, long antennae, poison claws, predators
• Diplopoda – millipede
o 2 pair of legs (diplosegment), short antennae, repugnatorial glands, feed on decaying vegetation

Question 24

Insecta characters

Answer 24

• 4 wings
• Segmented body (3) – head, thorax, abdomen
• 6 legs

Question 25

Insect importance

Answer 25

• Plant community structure
• Nutrient recycling
• Pollination and seed dispersal
• Energy conversion in food web