Lecture 5

Question 1

how many known animal species are arthropoda?

Answer 1

-2/3

Question 2

what are the key aspects of the arthropoda phylum?

Answer 2

-found in nearly all habitats
-segmented body covered by a cuticle (hard exoskeleton)
-have joint appendages
-bilaterians
-most undergo metamorphosis
-have stepwise growth
-open circulatory system
-have tagmata

Question 3

what is the cuticle of an arthropod made up of?

Answer 3

-proteins
-chitin

Question 4

what joint appendages do arthropods have?

Answer 4

-leg joints
-claws
-fangs
-antennas

Question 5

what is the purpose of the leg joints in arthropods ?

Answer 5

-walking

Question 6

what is the purpose of arthropods having claws?

Answer 6

-defense
-intimidation
-sensing + feeding

Question 7

what is the purpose of arthropods having fangs?

Answer 7

-inject venom

Question 8

what is the purpose of arthropods having antennas? what does this tell us?

Answer 8

-sensation (interpret surroundings)
-they have undergone cephalization

Question 9

what does it mean to have an open circulatory system?

Answer 9

-hemolymph is circulated to organs + tissue spaces
-hemolymph leaves the heart and goes to arteries
-no veins to bring hemolymph back

Question 10

what are tagmata?

Answer 10

-grouped segments

Question 11

what 2 tagmata do arthropods have?

Answer 11

-cephalothorax (head + thorax)
-abdomen (many small segments)

Question 12

what are the clades found within the arthropods?

Answer 12

-chelicerata clade
-myriapoda clade
-hexapoda clade
-pancrustacea clade

Question 13

what 2 groups are within the chelicerata clade?

Answer 13

-eurypterids
-arachnids

Question 14

what are examples of eurypterids?

Answer 14

-horseshoe crabs
-sea spiders

Question 15

what are examples of arachnids?

Answer 15

-spiders
-scorpions
-ticks
-mites

Question 16

what does the cephalothorax house in the arachnids?

Answer 16

-poision glands

Question 17

what does the abdomen house in the arachnids?

Answer 17

-essentials organs
-heart
-reproductive structures
-digestive system
-silk glands

Question 18

how many pairs of appendages do arachnids have?

Answer 18

-6 pairs

Question 19

what is another name for fangs?

Answer 19

-chelicerae

Question 20

what is another name for claws?

Answer 20

-pedipalps

Question 21

how many pairs of legs do arachnids have?

Answer 21

-4 pairs

Question 22

do arachnids have antennae? if not, why?

Answer 22

-NO
-they have sensitive eyes

Question 23

what are the 2 groups within the myriapoda clade?

Answer 23

-centipedes
-millipedes

Question 24

what are key features of the centipedes?

Answer 24

-1 pair of legs per segment
-carnivorous (eat other animals)

Question 25

what are key features of the millipedes?

Answer 25

-2 pairs of legs per segment -found in forest + tropical environments -herbivorous (eats plants) -gente

Question 26

what is included in the hexapoda clade?

Answer 26

-very diverse (large) clade -insects + other 6 legged organisms

Question 27

what are key features of the hexapoda clade?

Answer 27

-in nearly every terrestrial habitat or in fresh water -undergo one of the two types of metamorphosis -lightweight chitinous exoskeleton -3 tagmata

Question 28

what are the two types of metamorphosis?

Answer 28

-complete metamorphosis -incomplete metamorphosis

Question 29

what is complete metamorphosis?

Answer 29

-larva to adult form -energetically expensive

Question 30

what are common larva forms?

Answer 30

-maggot -caterpillar -grub

Question 31

what are examples of animals within the hexapoda clade that go through complete metamorphosis?

Answer 31

-beetles -flies -moths -wasps -bees

Question 32

what is incomplete metamorphosis?

Answer 32

-juvenile form resembles the adult form -considered "true bugs"

Question 33

what are examples of animals within the hexapoda clade that go through incomplete metamorphosis?

Answer 33

-leaf hoppers -aphids -grass hoppers

Question 34

what are the 3 tagmata that a hexapoda animal has? how many segments for each?

Answer 34

-head (5 segments) -thorax (3 segments) -abdomen (up to 11 segments)

Question 35

what is included within the pancrustea clade?

Answer 35

-crustaceans + insects

Question 36

what are the 2 groups of crustaceans?

Answer 36

-1 more closely related to insects (sister taxa) -1 more closely related to myriapods rather than other crustaceans

Question 37

what type of group is crusteacae?

Answer 37

-paraphyletic group (expand over multiple groups)

Question 38

what 2 tagmata are found within crustecea?

Answer 38

-cephalothorax -abdomen/tail

Question 39

in crustacea, what are features of the cephalothorax?

Answer 39

-several antennae pairs -chelipeds (theoretical arms/front legs) -walking legs (varying #'s)

Question 40

in crustacea, what are features of the abdomen/tail?

Answer 40

-heavily muscled -helps movement in environments

Question 41

where did flight evolution first occur?

Answer 41

-hexapoda clade (arthropods)

Question 42

what are wings extensions of? are they considered appendages?

Answer 42

-extensions of the exoskeleton -not considered appendages

Question 43

what happens to wings when moulting/shedding stops?

Answer 43

-wings harden

Question 44

how do wings/flight provide evolutionary success?

Answer 44

-escape predators faster? -find food easier -move to new habitats quickly

Question 45

how are insects defined?

Answer 45

-have 3 body parts -6 legs -4 wings -2 antennae