Transcript Symmetry
Kingdom Animalia CHAPTERS 26-34 General Characteristics Kingdom Characteristics All move at some point in their lifecycles In our study of animals we will go from SIMPLEST to most COMPLEX. This evolutionary progression can be observed through the following trends: Cells TissuesOrgans Systems Radial Symmetry Bilateral Symmetry Aquatic Terrestrial No cephalization Cephalization Symmetry Radial Symmetry - organism can be cut in half in many ways and the halves will be mirror images. Bilateral Symmetry - organism can be cut in half one way to get two equal halves. Cephalization Cephalization- organism has a true anterior end/head with concentration of nerve cells This sea star is not cephalized This grasshopper is cephalized Phylum Porifera - sponges Characteristics: • means “pore bearer” • simplest animals • All aquatic Feeding: • filter feeding using protist-like choanocytes Choanocyte Nervous Response: • Can produce toxins Locomotion: • Sessile (non-moving) adults with free-swimming gametes (egg and sperm) Skeletal System: • Can be hard with spicules or soft with spongin Reproduction: • Reproduce both asexually (budding) and sexually (gametes meet in open waters) Symmetry: Asymmetrical – no ends or sides Phylum Cnidaria Jellyfish, corals, sea anemone, hydra Characteristics: •First to have tissues •Live in aquatic habitats Feeding Mechanisms: • Single body opening through which food enters and waste leaves • Digests food within gastrovascular cavity and absorbs into tissues Nervous response: • Can detect light, gravity, and touch • Stinging cells called nematocysts found inside cnidocytes are used for defense and feeding Locomotion: • Polyps are sessile • Medusas use jet propulsion Skeletal System • Two types of body plan, polyp (sessile) and medusa Reproduction • Sexual and asexual (budding) reproduction Symmetry: • Radial symmetry Phylum Platyhelminthes Flatworms: flukes, turbellarians, tapeworms Characteristics • First group with organs • First cephalized group Feeding: • Carnivores • Scavengers • Parasitic Defense Mechanisms: • Ganglia – cluster of nerve cells • Eyespot – detects light Locomotion: • Cilia and muscles Skeletal System (body plan): Acoelomate - solid body construction • There is no fluid-filled cavity (coelom) Reproduction: • Hermaphroditic - both sexes in one worm, two worms line up and exchange sperm Symmetry: • Bilateral Phylum Nematoda Roundworms: hookworms, heartworms, and pinworms Characteristics: • Freeliving and parasitic Feeding Mechanisms: • First group to have a separate mouth and anus • “tube within a tube” • Parasitic, predators, or herbivores Defense Mechanisms: • Ganglia (concentration of nervous tissue) • Sense organs to detect chemicals given off by prey or hosts Locomotion: • Use muscles to move through water or soil Skeletal System (body plan) • Pseudocoelomate - false body cavity • There is a cavity, but it is not lined with mesoderm tissue Reproduction: • Sexually, separate sexes • Parasitic roundworms usually have more than one host Symmetry: • bilateral Phylum Annelida Segmented worms: earthworms, leeches, polychaetes Distinguishing Characteristics: • Segments allow for more complex movement • First group with true organs and systems Symmetry: • Bilateral Skeletal System (Body Plan): • Coelomate - true body cavity completely lined with mesoderm Reproduction: • Hermaphroditic or separate sexes • Clitellum (labeled below) is used for fertilization Locomotion: • Two types of muscles that work together for movement • Setae on segments (hair-like bristles) Feeding: • Can be filter-feeders, predators, or detritovores (feed on decaying materials) Defense/ Nervous Response: • Well-developed nervous system • eyes Phylum Mollusca Class Gastropoda (snails & slugs), Class Bivalvia (clams & scallops), Class Cephalopoda (squids & octopi) Characteristics: • “soft bodied” Symmetry: • Bilateral Skeletal System: • Foot – flat part of snails or tentacles of cephalopods • Shell – internal or external • Mantle – tissue Reproduction: • Sexually – most release gametes in open water Feeding: • Gastropods use a radula – tongue-like with teeth • Octopi use jaws • Bivalves are filter-feeders Defense: • Hard shells secreted by the mantle • Cephalopods are highly intelligent with eyes and tentacle Locomotion: • Gastropods secrete mucus • Cephalopods use jet propulsion Name that Structure! 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Copy down the description and write the name of the structure. Uses flagella to move water through the sponge A large hole at the top of the sponge A spike-shaped structure inside sponges A stinging structure within a cnidocyte that looks like a tiny hair Cnidarian body form that is NOT sessile Light-sensing structure seen in the Planaria A cluster of nerve cells in the flatworm and roundworm The posterior opening of the digestive tract, first seen in Nematodes Structure used for fertilization in Annelids Tissue in the Mollusks that secretes the shell Phylum Arthropoda Class Insecta • 6 legs • ex-Beetles, wasps, ants Class Arachnida • 8 legs • Spiders, scorpions, ticks, mites Class Crustacea • 10 legs/appendages • crabs, crayfish, barnacle Characteristics: • “jointed legged/footed” • largest phylum-96% of all inverts -73% of these are insects • aquatic and terrestrial Symmetry: • bilateral Nervous Response • Well developed nervous system and brain •Compound eyes that detect movement and color Body Plan: •Three body parts-head, thorax, and abdomen • exoskeleton made of chitin-molted/shed as they grow Feeding • A little bit of everything: Herbivores, carnivores, omnivores, detritovores, filter-feeders, parasites, and blood-suckers Phylum Echinodermata • sea stars, sanddollars, sea biscuits, sea urchins, and sea cucumbers Characteristics • spiny skinned animals • only phylum that is entirely marine • Often keystone species-removal of them from their environment will cause the ecosystem to crash Symmetry- 5-part radial symmetry (bilateral as larva) Reproduction – sexual, release gametes in open water Locomotion • watervascular system pumps water through body for feeding and movement • Tube feet Feeding • Sea stars open mollusks with tube feet, push the stomach out of the mouth, and digest the mollusk in its shell Nervous Response • no highly developed nervous system • Sense light, gravity, and chemicals