Exam 3 Ecdysozoans Phyla Nematoda and Arthropoda

Question 1

Ecdysozoans

Answer 1

ecdysis – molting of cuticle
•Cuticle - tough layer outside of the skin
•Have to shed cuticle to grow

Question 2

phylum nematoda

Answer 2

nematodes, roundworms

body covered in tough cuticle
complete digestive tract
0.1-2.5mm long

Question 3

most abudant type of animal

Answer 3

nematodes!
found in marine, freshwaters, soils, tropics, and polar regions

Question 4

nematodes can be

Answer 4

free living or parasitic

-free living species feed on algea, fungi, small animals, fecal matter, decaying matter, bacteria

-parasitic individuals feed on plant or animal tissues

Question 5

harmful nematodes

Answer 5

heart worms, elephantiasis, crop pests
-encysted in muscle tissue

Question 6

beneficial nematodes

Answer 6

natural pest control
decomposers

Question 7

phylum Arthropoda

Answer 7

insects, arachnids, centipedes, millipedes, crustaceans

Question 8

characteristics of Arthropods

Answer 8

segmented body, exoskeleton, paired, jointed appendages (“jointed foot”)

Question 9

all arthropods have

Answer 9

a cuticle/ exoskeleton of protein and chitin

Question 10

purposes of exoskeleton

Answer 10

attachment for muscles
prevents drying out

Question 11

Arthropod senses

Answer 11

well developed
simple eyes-detect light
compound eyes- form images
olfactory receptors- smell
antennae- touch/smell/taste

Question 12

arthropod respiration

Answer 12

terrestrial arthropods breathe through holes called spiracles that lead to trachea
aquatic arthropods breathe with gills

Question 13

phylum arthropoda
subphylum Chelicerata

Answer 13

horseshoe crabs (marines) and arachnids (terrestrial)
2 body regions: Cephalothorax and abdomen
simple eye (single lens)

Question 14

chelicerates have

Answer 14

6 pairs of appendages
Chelicera- pincers/fangs
pedipalps- sensing, feeding, defense, reproduction
4 pairs walking legs

Question 15

Horseshoe crabs

Answer 15

not true crabs
living fossils

Question 16

Arachnids

Answer 16

harvestman, spiders, mites and ticks, scorpions, tailless whip scorpion, whip scorpion, camel “spider”

Question 17

most common arachnids

Answer 17

spiders
-pierce prey with hollow chelicerae
secrete digestive juices, suck up fluid
make silk for webs, dispersal, escape
well developed eyes

Question 18

types of webs

Answer 18

orb webs, sheet webs, cob webs, funnel webs

Question 19

Phylum Arthropoda
subphylum Myriapoda

Answer 19

millipedes and centipedes
“many legs”
all terrestrial
body regions: head, many body segments

Question 20

millipedes

Answer 20

2 pairs legs/ segment
live in humid conditions, forest floor, leaf litter, dead wood, soil
most can burrow into soil
Detritivores- eat decaying plant matter
important decomposers

Question 21

Centipedes

Answer 21

1 pair legs/ segment
also found in soil, leaf litter, logs

predators, stab prey with poison fangs, eat other arthropods

Question 22

phylum arthropoda
subphylum crustacea

Answer 22

(paraphyletic)
msot are marine, freshwater
3 body regions : head, thorax, abdomen
lots of appendages

rolly pollies are terrestrial crustaceans

Question 23

crustaceans appendages

Answer 23

head
-sensory appendages- antennae
-feeding appendages
== mandibles- jaws
==Maxillae- tasting, manipulating food
== Maxillipeds- feedings

Question 24

crustacean appendages

Answer 24

Thorax
-chelipeds- pinchers, defense
-walking legs- locomotion

Abdomen
-swimmerets- locomotion

Question 25

crustacean examples

Answer 25

lobster, crayfish, shrimp, crabs
have carapace over dorsal side
most are scavengers

Question 26

Bannacles

Answer 26

sessile crustaceans
hard shell- calcium carbonate
anchor to surfaces
live in shallow, intertidal areas
filter feeders- jointed legs are modified into feathery cirri

Question 27

barnacles are

Answer 27

hermaphrodites
beneficial for sessile animals’
have the largest penis to body ratio of any animal

Question 28

phylum Arthropoda
class insecta

Answer 28

insects
80% all animals are arthropods
75% of all animals are insects
insects are most diverse taxa of animals

Question 29

characteristics of insects

Answer 29

3 pairs of legs
0-2 pairs of wings
3 body regions
head, thorax, abdomen

Question 30

insect sensory organs

Answer 30

compound eyes+simple eyes
1 pair antennae

Question 31

insect mouthparts and feeding type

Answer 31

Butterflies- siphoning- suck nectar

true bugs- piercing, sucking- suck plant fluid, insect fluid

Chewing- hard mandibles side to side

honey bees- chewing, lapping nectar and pollen

house flies- sponging, sponge up fluids

Question 32

insects mold to grow larger

Answer 32

incomplete metamorphosis
juveniles look like adults
life stages:
egg, nymph, adult
nymphs eat
adults have wings and are sexually mature

Question 33

complete metamorphosis

Answer 33

juveniles do not look like adults
life stages: egg, larva, pula, adult
larvae eat
adults have wings an are sexually mature

Question 34

pollination

Answer 34

required for 35% of food production globally

primarily pollination from bees
3/4 of leading food crops dependent upon animal pollination
$213 billion/ yr globally