Post on 27-Mar-2015
Arthropoda
Tavia Sin and Kelly Chen
The most successful of all animal phyla
http://www.ucmp.berkeley.edu/arthropoda/arthropoda.html
ArthropodaCheliceroforms-mostly terrestrial or marine; have chelicerae
Myriapods-terrestrial; have antennae and legs
Hexapods-mostly terrestrial; have antennae, legs (and sometimes wings), and segmented body
Crustaceans-mostly marine and freshwater; have antennae, legs, and segmented body
Kelly Chen
Sample AnimalsCheliceriforms-sea spiders, horseshoe crabs, scorpions, ticks, mites, spidersMyriapods-centipedes, millipedesHexapods-insects and their wingless, six-legged relativesCrustaceans-crabs, lobsters, shrimps, barnacles, and many others
http://kdhellner.tripod.com/id19.html Kelly Chen
Body Cavity (coelom)Coelom does exist but is not the main body cavityHemocoel-made up of the body sinuses, which are spaces surrounding the tissues and organsCoelom that forms in embryo becomes reduced
Kelly Chen
Body SymmetryBilateral symmetry
http://biology.clc.uc.edu/Courses/bio106/arthrpod.htm Kelly Chen
Nervous SystemWell-developed, mesodermal, ventral, solid nerve cordVentral-Pertaining to the front or anterior of any structure
http://bio1151b.nicerweb.net/Locked/media/ch33/ Kelly Chen
Circulatory System
Open circulatory system Fluid called hemolymph is
propelled by a heart through short arteries into sinuses
Hemolymph reenters the heart through pores equipped with valves
Kelly Chen
Digestive SystemAppendages are adapted to form mouthpartsSpiders use chelicerae to chew prey while spilling digestive juices on itMyriapods and insects use jaw-like mandibles to eat Exhibit almost every feeding mode: carnivores, herbivores, detritus feeders, filter feeders, and parasites
http://matthew.gray.org/2006_09_01_archive.html Kelly Chen
Excretory SystemGreen glands (crustaceans)- collect residue from the blood and body; connected to excretory pores under antennae.
Mapighian tubules (insects)- gather wastes from blood to release into intestine by excretory ducts.
Coxal glands (arachnids)-located in cephalothorax near limbs; participate in excretion.
Tavia Sin
Locomotion/MusculatureInsects fly to escape predators, find food and mates, and move to new habitats.
Most have one or two pairs of wings emerging from dorsal side of thorax.
Wings are extensions of the exoskeleton so leg use is not affected.
http://biology.clc.uc.edu/Courses/bio106/arthrpod.htm Tavia Sin
Skeletal TypeExoskeleton -external skeleton constructed from layers of protein and polysaccharide chitin. Molting (Ecdysis) –an arthropod sheds its exoskeleton and produces a larger one to grow in.
http://bio1151b.nicerweb.net/Locked/media/ch32/ Tavia Sin
Sensory Structure/Features
Well-developed sensory organs, including eyes, olfactory(smell) receptors, and antennae that function in both touch and smell. Most are concentrated at the anterior end of the animal.
Cheliceriforms lack antennae
http://photography.nationalgeographic.com/photography/enlarge/callicore-neglecta-butterfly-sartore.html
Tavia Sin
ReproductionIncomplete metamorphosis- young (nymphs) resemble adults but are smaller, have different proportions, and have no wings.
Complete metamorphosis- larval stage (eating, growing), middle stage (pupal), adult stage (dispersal, reproduction)
Reproduction is usually sexual, with separate male and female individuals.
http://teacher.scholastic.com/activities/explorations/bug/libraryarticle.asp?ItemID=126&SubjectID=145&categoryID=4
Tavia Sinhttp://www.dpughphoto.com/mason_farm.htm
Gas ExchangeGills with thin, feathery extensions- increase surface area in contact with surrounding water.
Tracheal systems- branched air ducts leading into interior from pores in exoskeleton.
Book lungs- stacked plates contained internally; increase surface area, enhance exchange of O2 and CO2.
Tavia Sin
http://bio1151b.nicerweb.net/Locked/media/ch33/
Other Unique FeaturesLargely related to segmentation , hard exoskeleton, and jointed appendages
Arthropod means “jointed feet”
As they evolved, the segments tended to fuse and become fewer in number and the appendages became specialized for a variety of functions
http://krlphotography.typepad.com/photos/historical_artifacts/trilobite1.htmlTavia Sin
Quiz Question #1
What skeletal type do arthropods have?
Answer #1
Exoskeleton
Quiz Question #2
true or false: Arthropods reproduce asexually
Answer #2
False
Quiz Question #3
What sensory organ functions in both touch and smell in most arthropods?
a) eyes b) olfactory receptors c) antennae d) arms
Answer #3
C) Antennae
Quiz Question #4
The process of shedding the exoskeleton is called______
Answer #4
Molting, ecdysis