Transcript File - Mr. Haan`s Science

Arthropods
CHAPTER 22
A. Introduction
1. Largest group of living organisms on earth
2. Literal meaning: jointed foot
3. Includes: spiders, scorpions, ticks, mites, crustaceans,
millipedes, centipedes, insects, and others
4. Similar to annelids: segmented, segmented appendages
B. Characteristics
1. Bi-lateral symmetry
2. Exoskeleton of chitin
a.
b.
c.
Support
Protection
Can’t grow with body = molting
3. Have nervous system, sensory receptors, and digestive
tract
4. Open circulatory system
5. Respiration: body surface, gills, or book lungs
6. Reduced coelom (body cavity)
7. Separate sexes: external or internal eggs
C. Subphylum Trilobita
1. Extinct in the mass extinction of the Permian era
2. Trilobites
D. Subphylum Chelicerata
1. 2 body parts: cephalothorax and abdomen
2. 4 pairs of legs
3. Order Araneae (spiders)
a. Appendages: 6 pairs
1) 4 pairs of legs
2) 1 pair chelicerae – mouth parts
3) 1 pair pedipalps – sensory
b. No antennae
c. Feed on insects – most suck fluids from prey
https://www.youtube.com/watch?v=ijxdB9G1JIQ
d. Eight simple eyes – poor vision
e. Book lungs
1) Parallel air pockets
2) Extend into a blood filled chamber
f. Paired spinnerets – make silk stronger than steel
g. Chelicerae are fangs with poison
1) Black widow
2) Brown recluse
4. Order: Opiliones (harvestmen)
a. AKA: daddy long legs
b. Can lose a leg for safety purposes
c. Abdomen and cephalothorax broadly joined – no
pedicel
d. NOT SPIDERS
1) Do not spin web
2) Have no venom
3) Single pair of eyes
https://www.youtube.com/watch?v=0JK2dR8ei5E
https://www.youtube.com/watch?v=OWASwBWyUXI
5. Order Acarina: Ticks and mites
a. Cephalothorax and abdomen completely fused
b. Ticks
1) 25,000 species
2) Slightly larger than mites
3) Attach to host, pierce skin, and suck blood
4) Drop off when full to digest meal
5) Some are disease carriers: Lyme disease, Texas
cattle fever, Rocky Mountain spotted fever
TICK CHECK! - https://www.youtube.com/watch?v=27McsguL2Og
c. Mites
1) About 1-2 mm
2) Many attack plants by sucking juice from leaves and
stems (spider mites)
3) Some are parasites on humans in larva form (chiggers)
4) Usually less of a disease threat
5) One species (Canine Scabies) attacks hair follicles in
dogs causing skin disease called mange
Chigger Bites
6. Order Scorpionida
a. Night feeders of insects and spiders
b. Long narrow segmented tail ending in a venomous
stinger
c. Have 1 – 6 pairs of eyes
d. Usually hide during the day and feed at night
e. Venom of most is not harmful to humans
f. Scorpions give live birth and carry babies on their back
until the first molt of the babies
• Find the Scorpion
•
https://www.youtube.com/watch?v=jey8BWvYVAw
• Mating and Young
•
https://www.youtube.com/watch?v=CHmBBvJssdY
E. Subphylum Crustacea
https://www.youtube.com/watch?v=GYWtj5q_MVc
1. 30,000 species including lobsters, crayfish, shrimp,
crabs, and others
2. Head contains:
a) Pair of mandibles
b) 2 pairs of antenna
c) 2 pairs of maxilla (mouthparts)
3. Most have 16 – 20 segments
4. Many have carapace – hard covering extending over
head, thorax, and abdomen
5. Live in both water and land
6. Class Malacostra, Order Decapoda
a. Lobsters, crayfish, shrimp, and crabs
b. Appendages (crayfish characteristics)
1) Maxillipeds – food handling and eating
2) Chilipeds – Claws for defense
3) 4 pairs of walking legs
4) Swimmerets
a) 3 – 5 pairs
b) Males – first pair modified for copulation
c) Female – nursery for eggs and young
5) Uropods – act as rudders when moving
c. Molting
1) Necessary as crayfish grows
2) Premolt – salts are absorbed from cuticle
3) Enzymes digest old endocuticle
4) New endocuticle forms, old cuticle splits and crayfish
crawls out
https://www.youtube.com/watch?v=9CvPaIpVrqo
d. Colors: chromatophores – specialized cells which give
pigments
e. Eating and digestion
1) Chelipeds capture food (racist goldfish)
2) Hold and crush food with maxillipeds
3) Mandibles and maxilla ingest food
https://www.youtube.com/watch?v=3DYhOzGRXhY
4) 2 part stomach
a) Cardiac
i. Contains gastric mill
ii. 3 teeth for grinding
up swallowed food
b) Pyloric
i. Receives food from cardiac stomach
ii. Digestion and passes it into the intestines
5) Solid waste from digestion exits from anus
6) Liquid waste, mainly ammonia, urea, and uric acid
excreted from the antennal glands or maxillary glands
located at the base of the antennae
f. Food
1) Important for animals like bass, opossum, and raccoons
https://www.youtube.com/watch?v=OMWPssGI0LM
2) Humans eat them as well
g. Respiration – gills under carapace on sides of body
h. Circulation
1) Mostly open with a heart and several arteries
2) Blood is also moved by organs and tissues pushing
blood around in open cavities inside the body
i. Nervous system
1) Central nervous system
2) Brain with a double ventral nerve cord attached to
ganglion in each segment of the body
3) Compound eyes located on the ends of eye stalks
j. Reproduction – eggs fertilized and held in swimmerets
until they hatch
F. Subphylum Uniramia
1. Class Chilopoda – centipedes
a. 1 pair of legs per segment
b. Carnivores
c. Inject poison into prey with claws https://www.youtube.com/watch?v=TzF0GKfOvRY
d.
Usually found in damp places like under rocks and in
soil
2. Class Diplopoda – millipedes
a. 2 pairs of legs per segment
b. Eat plants
c. Shy and slower moving - https://www.youtube.com/watch?v=N9cjqjdxP0A
d. Roll up when scared
e. Usually found in damp places like under rocks and soil
Millipedes
Centipedes
2 pairs of legs per segment
Slower
1 pair of legs per segment
Faster
Herbivores
Rounded body
Roll/Spray chemical when threatened
Carnivores
Flattened body
Run/Bite when threatened
3. Class Insecta
a. Characteristics
1) More kinds of insects than all other animal species
all together (as many as 10 million species exist)
2) Could be 300 million times as many insects as
humans on Earth
3) Exoskeleton and jointed appendages
4) 3 body segments – head, thorax, abdomen
5) One pair of antennae
6) 3 pairs of legs
a) Connected to the thorax
b) Sometimes different sizes –
larger are used for jumping
7) Abdomen has 11 segments
8) Piercing and chewing mouth types
9) Usually two pairs of wings
b. Beneficial
1) Cross fertilization and pollination of crops
2) Production of useful/valuable substances: honey, wax,
and silk
3) Predation – control of many harmful insects
4) Important decomposers: maggots
5) Important in the food chain/web
c. Harmful
1) Eat human food crops
2) Destruction of property: termites, moths, weevils, ants
3) Carry diseases: plague, malaria, typhoid, Chaga’s
disease, West Nile, Zika
4) Irritation to humans
d. Metamorphosis
1) A huge change in appearance
2) Complete - https://www.youtube.com/watch?v=ZuHwRiVF77o
a) Larva look nothing like adult
b) Butterflies, moths, flies
c) 4 Stages
i. Egg stage
ii. Larva
iii. Pupa – wrapped in a chrysalis or cocoon
iv. Adult
3) Incomplete
a) Young look similar
to adults but often lack
wings
b) 3 Stages
i. Egg
ii. Nymph
iii. Adult
e. Insect behavior
1) Most live alone, some insects are social and cannot
survive alone
2) Hives and colonies
a) Colony – group of insects living together
b) Hive – colony specifically of bees
c) Insects of hives and
colonies all have specific jobs
and are very organized https://www.youtube.com/watch?v=vG-QZOTc5_Q
f. Defense (life on insects)
1) Camouflage
2) Stingers
3) Chemicals
4) Warning colors
g. Respiration
1) Most take in O2 and release CO2 through tubules called
trachea
2) Trachea open to outside of body through openings
called spiracles
3) Some aquatic nymphs or larva may have gills
h. Reproduction
1) Sexual
2) Do not care for young so thousands – millions of eggs
are laid to ensure survival
i. Communication
1) Have well developed senses allowing them to respond
to external signals
2) Sensitive to light – either attract or avoid
3) Pheromones – to attract mates
4) Some use bioluminescence to attract mates
5) Respond to certain frequencies or sounds
- Some mosquitos can only hear the frequency of the
female wing beats of the same species
6) Bee Dance - https://www.youtube.com/watch?v=2S-ozxpIrdI
j. Orders
1) Orthoptera – Grasshoppers,
crickets, cockroaches,
katydids
2) Hemiptera – all true bugs
3) Coleoptera – beetles and ladybugs
4) Lepidoptera – butterflies and moths
5) Hymenoptera – bees, wasps, ants
Hemiptera vs. Coleoptera
HEMIPTERA
COLEOPTERA