Phylum arthropoda
Sponsored Links
This presentation is the property of its rightful owner.
1 / 67

Phylum Arthropoda PowerPoint PPT Presentation

  • Uploaded on
  • Presentation posted in: General

Phylum Arthropoda. Read Chap 31 pgs. 681-703 Dichotomous Key. What is Entomology?. The study of insects (and their near relatives). Species Diversity. PLANTS. INSECTS. OTHER ANIMALS. OTHER ARTHROPODS. Arthropods. Jointed-legged invertebrates. CLASSIFICATION

Download Presentation

Phylum Arthropoda

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Phylum Arthropoda

  • Read Chap 31 pgs. 681-703

  • Dichotomous Key

Whatis Entomology?

The study of insects

(and their near relatives).

Species Diversity








Jointed-legged invertebrates



  • SUB-Trilobita Crustacea Chelicerata Uniramia


  • CLASSextinct Crustacea Arachnida Chilopoda

  • Diplopoda

  • Insecta

  • ORDER 16

Characteristics of Phylum Arthropoda

  • - Segmented bodies are arranged into regions, called tagmata (in insects = head, thorax, abdomen).

  • - Paired appendages (e.g., legs, antennae, wings) are jointed.

  • - Possess chitinous exoskeleton that must be shed during growth.

  • Open circulatory system

  • Nervous system is ventral (belly) and the circulatory system is open and dorsal (back).

  • Complete digestive system

Head Thorax Abdomen


  • Major reason for success!

  • Provides

    • Support

    • Protection

    • Prevention of dehydration

    • Sites for muscle attachment


  • Change body form from immature (larval) stages to adult forms

  • Reduces competition between stages for

    • Food

    • Living space

Taxonomy of Arthropods

  • 4 subphyla

    • Trilobitomorpha (all extinct)

    • Chelicerata

    • Crustacea

    • Uniramia

The state fossil of Ohio

Subphylum Chelicerata (plier like)

  • Horseshoe crabs

  • Spiders

  • Mites

  • Ticks

  • Scorpions


Scorpion Anatomy

Scorpion Head




Orders of Arachnids



(a mite)





Pseudo scorpion(pseudo means “false”)

Mite and Tick Body Regions

pedipalps &




Common ticks

American dog tick male


Rocky mountain spotted fever

Blacklegged (deer) tick female

- Vectors Lyme disease

American dog tick female laying egg mass (1000-2000 eggs!).


Clover mites

Twospotted spider mites

Velvet mite

Predatory mite

Phalanges (daddy-long-legs)



Spider Anatomy


chelicera (fang)


narrow waist




Chelicera (fang)



Wolf spider with egg case

Spitting spider

Orbweaving spider


Dangerous Spiders

Black widow with egg case

Brown recluse


Interesting modifications

  • Spinnerets

  • Malpighian tubules

Subphylum Crustacea

  • Shrimp, lobsters, crayfish

  • Fairy shrimp, brine shrimp

  • Water fleas

  • Barnacles


Crayfish cephalothorax


Sow bug (Isopoda),

a terrestrial crustacean

CLASS CRUSTACEA tremendous variety

  • daphnia, crabs, lobster, pill bugs, crayfish

  • *primarily aquatic, mostly marine 25,000 species

  • (motile sessile microscopic, 2 ft. or more)

  • *gills, at least 5 pairs of legs

  • *carapace- shield to protect vital organs

  • * branched antennae

  • see lab for specifics of this group

Subphylum Uniramia

  • Class Diplopoda (millipedes)

  • Class Chilopoda (centipedes)

  • Class Hexapoda (insects)

[one pair of antennae, head & trunk regions, trunk with many pairs of legs]

Diplopod (Millipede)

Two pair of legs per visible segment, attached under body.

Chilopod (Centipede)

Pair of fangs under head, one pair legs per visible segment - attached to side of body.

Symphyla (Symphyla)[garden centipede]

No fangs, no eyes, legs attached to side of body.

Millipede (Diplopoda)

Centipede (Chilopoda)

Garden centipede (Symphyla)

Nervous System

  • Johnston’s organs (hearing - on antennae)

  • Tympanic organs (hearing – on legs or body)

  • Compound eyes (facets – ommatidia – fused)

  • Simple eyes (ocelli)

Economic Impact of Arthropods

1. Name two effects of each major group has on mankind (good and bad).

Crustacea, Millipede, Centipede, Arachnida

2. For insects, list 4 good things that they do and 4 bad things that they are responsible for.


Head Thorax Abdomen

How Many Kinds Insects are there in the world?

Possibly 3,000,000 unidentified species

  • 1,000,000 species known

Classification of Japanese Beetle

  • Kingdom Animalia

  • Phylum Arthropoda

  • Class Insecta

  • Order Coleoptera

  • Family Scarabaeidae

  • Genus Popillia

  • Species japonica

*molting "ecdysiast"-

  • hormone induced changes to create new and larger exoskeleton

  • desiccation potential

  • "instars" periods between molts

  • vulnerable while exchanging skeleton

  • may continue throughout life or end at a particular point


  • foregut

  • ingestion, mechanical breakdown and storage

  • midgut

  • chemical digestion, absorption, enzymatic,

  • (sounds like our intestines)

  • hindgut

  • absorption of water and formation of feces

RESPIRATION (handout in binder )

Open Circulatory System- blood not confined to the vessels

  • Pericardial sinus- space for gas exchange around the heart (open space)

  • Gases into the body through the spiracles in the exoskeleton (waxy)

  • Trachae- tubes from spiracles to vital locations

  • ***blood is not vital for gas exchange*** rare to find hemoglobin

  • Tracheoles- branches with membranes at the end fluid tipped perhaps

other possible modifications

  • *book lungs- look like corrugated cardboard

  • *coordination between opening and closing of spiracles to pump the air in (think of a tire pump)

  • *air sacs at the end of the tracheoles for increased surface area

  • *gills


  • (insects mostly) video Swarming Hordes

  • Communication

  • Chemical, visual, and auditory



Pheromones- airborne chemicals are used by males can find females for mating purposes

  • 1) releasers- immediate behavior change

  • 2) primers- profound physiological changes

Bug’s Life

  • humans have exploited this with bug traps (June bugs)

  • Scent trails can be left on the ground during food foraging trips (A BUG’S Life video)

  • plants mimic scents to attract pollinators

  • death pheromones- remove ant from a colony and paint with the chemical, return to colony and is repeatedly carried away.

  • 0.00000001 grams silkworm female can be detected 2 miles


  • *visual-

  • can see ultraviolet wavelengths of light

  • Fireflies use light to attract mates Males are in the air while females remain on the ground


  • *Sound

  • production in grasshoppers, crickets and cicadas

  • scraping of limbs on the exoskeleton, air vibrations along the exoskeleton caused by muscle movement


  • visual, camouflage (hide or lie in ambush)


  • (faked you out!)

  • Now you’re dinner!

SOCIAL BEHAVIOR requires communication

  • A colony can have the same effect as a large single animal

  • Hey, hey, hey do what I tell you

  • Division of Labor

  • ex. bee hive

  • 80,000 members

  • polymorphic anatomy

  • Drone Worker Queen

What a life?

  • worker 6 wk. life, sterile female, reproductive organs become stinger, 1,000 s

  • drone- (n) reproductive male, only for mating, 100s, die after mating, killed if food is low

  • queen bee- reproductive female, 5-6 year life

worker behavior

  • week 1

  • feed queen, drones, larva, secrete "royal jelly"

  • weeks 2-4

  • secrete wax, clean, repair hive, guard,

  • fan in fresh air

  • weeks 5-6

  • gather pollen and nectar

Stand for the QUEEN!

  • QUEEN is like other female but she eats "ROYAL JELLY"

  • Secretes "queen factor" which prevents other females from becoming reproductive. Mates once and stores sperm

Butt wiggle dance


  • Incomplete-

  • grasshopper and termite

  • Egg- nymph- adult

  • Immature adult look alike, small ,non-sexual


  • Complete

  • butterfly, moth (most insects)

  • Egg-larva-pupa- adult



  • Controlling factors

  • Sequential expression of genes

  • Brain hormone stimulates molting hormone in thorax gland

Molting hormone released in both where juvenile hormone is present

  • JH MH larva molts

  • JH MH larva pupates

  • JH MH pupa to adult

  • Importance of metamorphosis?

  • No competition for food

  • What the caterpillar eats the adult does not

  • Name ________________________ Period ________


  • Materials

  • 1 lab set “Dissecting a Crustacean- the Crayfish”

  • Dissecting microscope

  • Dissecting tools

  • STEP 1Examine the external anatomy of a crayfish

  • Follow Procedure A of the LAB NOT STEP 5 ON LIVE CRAYFISH

  • Compare the live specimens w/ diagrams on sheets

  • Describe texture of the crayfish

  • STEP 2Test Crayfish Behavior

  • Lay live crayfish in a clear plastic container

  • Observe/record behavior for 4-5 minutes

  • Observe/record movements (O/R)

  • O/R responses to stimuli on a table with 2 columns (see below)

    • Bubbles gently blown into the water

    • Touch with a probe (Anterior/ Posterior)

    • Touch chelipeds, walking legs, middle of dorsal, telson

    • Darken ½ of the container

    • Shine a light on the anterior

  • 5. Drop one piece of food (shrimp pellet) near the anterior O/R feeding behavior

  • STEP 3 Crayfish Dissection

  • Follow instructions in the lab papers.

  • STEP 4 Reading Assignments

  • 715-719, 720-734


  • StimulusResponse

  • Probe telson

  • walking leg

Rules for writing a dichotomous key

  • 1. always couplets

  • 2. total number of couplets is one less than the total number of items

  • 3. no overlapping measurements

  • 4. only physical descriptions (no behaviors)

  • 5. start couplets with the same word

Test Topics

  • Dichotomous Key, Video “Swarming Hordes”, Arthropod Notes,

  • Lab Crayfish dissection and Behavior, Insect Social Behavior,

  • SEQUENTIAL COMPARISON INDEX, relationship between annelids and arthropods, Read (general 715-719, crustacea729-734) Chap 31 in regular BIOLOGY text

  • Login