 Most diverse in appearance  Heterotrophs, multicellular, eukaryotes, no cell walls  Cells -> tissues- perform a specific function  Ex: epithelial, muscle, nerve, etc.  Over 95% of all animals = invertebrates

 Things look the way they do in order to perform a certain function  Study of these functions: physiology  Homeostasis  Feedback inhibition: product (result) of a process stops/limits the process ▪ (ex: dog panting)

 1. feeding- ingest nutrients  2. respiration- O2 in / CO2 out  3. circulation- nutrients/gases/waste  4. excretion- get rid of wastes  5. response- receive/process info + react  6. movement- motility + feeding  7. reproduction- sexual: increase genetic diversity  asexual: increase population #s

 Most complex animals have:  increase specialization  bilateral symmetry  cephalization w/ sense organs  body cavity (coelom)

 Blastula: protostome vs. deuterostome  Germ layers  Endoderm (inner)  Mesoderm (middle)  Ectoderm (outer)  Body symmetry  Radial/ bilateral  Anterior/posterior  Dorsal/ventral

 Dissecting pan  Pins  Scissors  Probe  Hand lens  Forceps  Scalpel/blade  Apron  Goggles  Gloves

Chapters 26, 27 & 28

 Sea sponges  Sessile- don’t move  Very different from other animals  Very few specialized cells

 Choanocytes: specialized cells- use flagella to move water inside open body cavity  Osculum: large opening where water leaves

 Feeding- filter feeders  Resp/Circ/Excr- water movement  Response- can secrete toxins to ward off predators  Reproduction- sexual (larva) and asexual (budding or gemmules)

 Soft bodies  Carnivores  Stinging tentacles  Ex: jellyfish, hydras, sea anemones, corals

 Cnidocytes: stinging cells  Nematocysts: poison-filled stinging structure  Radial symmetry  Polyp vs. medusa stages

 Feeding- gastrovascular cavity (one opening)  Resp/Circ/Excr- diffusion  Response-nerve net: network of nerve cells that react to stimuli  Movement- hydrostatic skeleton  Reproduction- asexual (budding) and sexual (separate sexes)

 flatworms  Acoelomates  Bilateral symmetry  Cephalization  Ex: flukes, tapeworms

 Feeding:  Free-living: 1 opening digestive cavity ▪ Pharynx extends out- brings food in  Parasitic: eat digested food  Resp/Circ/Excr- diffusion  Flame cells: remove excess water/waste

 Response- ganglia: group of nerve cells  Eyespot: detect light  Movement- cilia and muscles  Reproduction- sexual (hermaphrodites)  asexual fission: organism splits in two

 Roundworms  Pseudocoelomates  C. elegans- 1 st organism to have its entire genome sequenced!

 Feeding- 2 openings in digestive tract  mouth and anus  Resp/Circ/Excr- diffusion  Response- ganglia + nerves run length of body  Movement- hydrostatic + muscles along body  Reproduction- sexual (separate sexes)

 Trichinosis- burrows in organs- painful  Filarial- elephantitis swelling  Ascarid- parasitic- causes malnutrition  Hookworms- enter blood stream and intestines- cause weakness and poor growth

 Ringed worms  Segmented bodies separated by septa  Some segments specialized  Coelomates  Ex: earthworms, leeches

 Feeding- pharynx or filter feeders  Crop (stores food) and gizzard (breaks it down)  Circulation- closed (dorsal and ventral vessels)  Respiration- gills or moist skin (diffusion)  Excretion- anus and nephridia (cellular waste)

 Response- well-developed brain  Movement- specialized muscles  Longitudinal and circular  Reproduction- most sexual (some hermaphrodites)

 Soft-bodied  Usually have a shell (internal/external)  VERY diverse  Ex: snails, slugs, clams, squid, octopus  Share similar developmental stages  coelomates

 Main Parts:  1. foot- used for crawling, hunting, burrowing, etc.  2. mantle- covers body like a coat  3. shell- glands secrete calcium carbonate  4. visceral mass- internal organs

 Feeding- radula, jaws, siphon  Respiration- gills, moist mantle  Circulation- open or closed  Excretion- nephridia

 Response- from ganglia -> highly developed brains (octopus)  Movement- secrete mucus, jet propulsion  Reproduction- external/internal, separate sex/hermaphrodites

 3 types:  Gastropod (snails)  Bivalves (clams)  Cephalopods (octopus)  Human uses:  Filter feeders build up high concentrations of pollutants- scientists can use to monitor water  Some snails don’t get cancer- use for research

 “jointed foot”  Most diverse and successful phylum  Ex: crabs, spiders, horseshoe crabs and insects

 Segmented body  # varies  Tough exoskeleton  Chitin  Varies in texture (leathery, waxy, hard)  Jointed appendages  Evolution- decreased # of segments, specialized appendages

 Feeding- mouthparts vary  Suckers, filters, fangs etc.  Respiration- tracheal tubes  Use of spiracles, book lungs, gills  Circulation- open system- heart  Excretion- Malpighian tubules  N wastes into feces (land) or water (aquatic)

 Response- brain->nerve cord->ganglia in appendages  Movement- muscle cells contract- pull on exoskeleton to fly, swim, walk, etc.  Reproduction- land= internal fertilization  Aquatic= external or internal  Molting: shed exoskeleton and grow a new one- controlled by endocrine system

 Classified based on #/structure of segments and appendages (mouthparts)  Subphyla:  Crustacea  Chelicerata  Uniramia

 Mostly aquatic (+pillbugs)  2 pairs of antennae  2-3 body sections  cephalothorax, thorax, abdomen  Chewing mouthparts (mandibles)  ex: shrimp, crayfish, lobster, crabs, barnacles

 Chelicerae mouthparts- “fangs”  2 body sections  4 pairs of legs  Spiders (Arachnids)  Venom/digestive enzymes  Silk glands  Horseshoe crabs* (Merostomata)  Oldest living arthropod  5 pairs of legs

 Jaws, 1 pair antennae, unbranched appendages  Insects:  3 body parts and 3 pairs legs  Advanced response system ▪ Compound eye, receptors, sensory hairs, ears  Metamorphosis (incomplete and complete)  Advanced communication ▪ Pheromones and dances

 “spiny skin”  endoskeleton  water vascular system*  tube feet  radial symmetry  Closely related to humans!  Bilateral larva, deuterostomes

 Feeding- scraping, filter, predators  Can extend stomach out of body  Respiration/Circulation- WVS  Water in thru madreporite  Excretion- wastes out anus (digestive) or diffusion (cellular)

 Response- nerve ring- extends into arms  eye spots  Movement- tube feet, WVS, spines, muscles  Reproduction- external fertilization

 Sea urchins/sand dollars  Brittle stars: long/flexible arms- very fast  Sea cucumbers: “warty moving pickles”  Sea stars: can regenerate parts, carnivores  Crown of Thorns  Sea lilies/feather stars: oldest- filter feeders