Section 20.3- Arachnids, Centipedes, and Millipedes

Question 1

small insectlike arthropods

Answer 1

arachnids

Question 2

examples of arachnids

Answer 2

spiders,
daddy longlegs,
mites and ticks
scorpions

Question 3

body regions of a spider

Answer 3

cephalothorax (fused head and thorax)
abdomen

Question 4

spiders have only ______________ eyes

Answer 4

simple

Question 5

the four spiders in N American that have a harmful bite

Answer 5

two species of black widows
brown recluse
red widow

Question 6

the thin waist of a spider that separates the cephalothorax and the abdomen of a spider’s exoskeleton

Answer 6

pedicel

Question 7

a pair of short appendages that a spider uses to seize and to kill or crush its prey

Answer 7

chelicerae

Question 8

have fangs that point inward and move in and out, crossing in the middle

Answer 8

true spiders

Question 9

have fangs that point down and move up and down

Answer 9

mygalomorphs

Question 10

the best known mygalomorph

Answer 10

tarantulas

Question 11

located beneath the chelicerae and is designed for sucking liquids

Answer 11

mouth

Question 12

an appendage that looks like a small leg, and is attached to each side of a spider’s mouth

Answer 12

pedipalp

Question 13

purpose of the pedipalp

Answer 13

cut and crush food

Question 14

a pad of hairs that surrounds the last leg segment

helps the spider cling to walls and ceilings

Answer 14

scopula

Question 15

although most spiders are nearsighted, these two spiders have excellent eyesight

Answer 15

jumping spiders
wolf spiders

Question 16

a spider has a _________________ stomach

Answer 16

sucking

Question 17

where a spider’s digestion is completed its liquification and absorbed through the walls into the blood

Answer 17

intestine

Question 18

is pale blue and contain many white blood cells

Answer 18

blood

Question 19

a long, slender, muscular tube that pumps blood to the whole body

Answer 19

heart

Question 20

a spider’s blood flows through _____________ in its body rather than through a ___________________ of blood vessels

Answer 20

open passages
closed system

Question 21

a spider’s respiratory system consist of both

Answer 21

trachea and book lungs

Question 22

located near the rear of the spider’s abdomen

where air enters through into the trachea

Answer 22

spiracles

Question 23

a special protein in the spider’s blood that carries oxygen in the spider’s blood

Answer 23

hemocyanin

Question 24

the organs that spiders use to spin silk

Answer 24

spinnerets

Question 25

where the male places his sperm during mating

Answer 25

female’s seminal receptacle

Question 26

the longest living of all spiders

Answer 26

tarantulas

Question 27

a group of arachnids famous for their long, spindly legs

Answer 27

daddy longlegs or harvestmen

Question 28

differences between spiders and daddy longlegs

Answer 28

1. harvestman has no constriction (waist)
2. harvestmen sense organs located on second pair of legs
3. harvestmen have pincerlike chelicerae instead of fangs
4. has only two simple eyes instead of 8
5. lack spinnerets
6. omnivores instead of just carnivores

Question 29

arachnids found in most temperate climates and in all tropical climates

are most active at night and crawl into dark places

most prominent feature is tail

Answer 29

scorpion

Question 30

all species of scorpions are either _______________________ or _____________

Answer 30

ovoviviparous
viviparous

Question 31

arachnids that make up an order of tiny blood-sucking insects that parasitize both man and animals

Answer 31

mites and ticks

Question 32

caterpillar-like creature that are often confused with each other, but have significant differences

Answer 32

centipedes and millipedes

Question 33

characteristics of a centipede…

Answer 33

1. flattened body
2. pair of long antennas
3. single pair of legs attached to each segment
4. poisonous

Question 34

characteristics of millipedes…

Answer 34

1. rounded bodies
2. short antennas
3. harmless
4. two pairs of legs per body segment

Question 35

millipedes are saprophytes, which means

Answer 35

they feed on mostly dead and decaying plant materials