7th grade ch. 2 sec. 2 arthropods

Ch. 2 Sec. 2

Arthropods

Characteristicsof

Arthropods

invertebrateexoskeleton

• external skeleton

segmented body

jointed appendages

antenna= contains

sense organs

•protects•preventsevaporation

moltingmolting• process of shedding outgrown exoskeleton

Yikes!  My Skeleton is Outside My Body!

soft shelled crab

(crab, shrimp) (spider, tick) (bee, fly)

metamorphosis• process in which an animal’s body

undergoes dramatic changes in form during its life cycle

Crab Larva This larva of a crab floats in the ocean with other microscopic animals.

- Arthropods

• .

A crustacean is an arthropod that has two or three body sections, five or more pairs of legs, & two pairs of antennae

arachnids

abdomen

combined head & body section

Red Knee Tarantula

examples of arachnids:

scorpionsdust mites

deer ticks

spiders• predators

• have hollow fangs-

1. inject venom into prey

2. turns tissues into mush3. uses fangs like straws to suck out mush

The Dangerous Brown Recluse Spider

This guy was bitten by a Brown Recluse spider.

Day 3

The following illustrates the progression of a brown recluse spider bite.

The affected skin actually dies on his body.

Day 5

Black widow spider

centipedes millipedes

1 pair of legs on each segment

2 pairs of legs on each segment

carnivores herbivores

More arthropod groups

centipede

• Millipedes in the Great Smoky

Mountains National Park in

Tennessee

When millipedes are disturbed, they can curl up into an armored ball and squirt an awful-smelling

liquid at a potential predator.

Arthropods

Crustaceans

include

have have have have

ArachnidsCentipedes

and millipedes

6 legs, 3 body sections

Four antennae

Insects

Eight legs, two body segments,

no antennae

Highly segmented body,1 or 2 pairs of legson each segment, 2

antennae

1. 2.

3. 4.