Classifying animals Classifying organisms, from the Animal Kingdom according to the principals of taxonomy
Thinker… Why is it thought that prokaryotic cells are more primitive than eukaryotic cells?
What Kingdom do I belong to? I am Prokaryotic. I can live almost anywhere. I reproduce asexually. I usually have a cell wall. I am heterotrophic (eat food) or autotrophic (make my own food.) Eubacteria
Plantae I am multicellular I have a cell wall I make my own food (autotroph)
Protista I might be prokaryotic or eukaryotic I live in moist habitats I can make my own food but some of my friends have to consume their food I can be plant-like or animal-like I can make you sick
Fungi I am a heterotroph I am sometimes confused with a plant I am usually multicellular I reproduce using spores
Archaebacteria I am prokaryotic I live in harsh conditions (salt lakes, hot springs and animal guts) I am a heterotroph I do have a cell wall, but it is different from my cousins the Eubacteria
Animalia I am multicellular I usually reproduce sexually My cells don’t have walls I can fly, swim, walk or run
Classifying animals There are six commonly recognized Kingdoms –Eubacteria, Archaebacteria, Protista, Fungi, Plantae and Animalia The animal kingdom can be split, further, into two main groups: animals with backbones (vertebrates) animals without backbones (invertebrates). 8Da
Phylum There are about 30 phyla in the animal kingdom. All but one of these phyla are invertebrates We belong to the one phyla that has vertebrates (Phylum Chordata)
Characteristics of all Animals Heterotrophic, multicellular eukaryotes. Cells lack cell walls. Specialized tissue: nervous & muscle tissue. Primarily sexual reproduction.
The Invertebrates… Can you think of what organisms might be included in the invertebrate group??? Of the approximately 30 phylum of invertebrates there are 5 you should know…
Invertebrates (5 main phylum) molluscs arthropods Annelida (segmented worms echinoderms cnidarians jellyfish 8Da
Phylum Cnidaria Exhibits radial symmetry. Cells organized into tissues. E.g., hydrozoans, jellyfish, sea anemones, sea fans and corals.
Phylum Cnidaria Two Main Cell Layers 1. Covers outer body surfaces. Some have muscle fibers or nerve nets. 2. Covers inner body surfaces. ** Mesoglea: A jelly-like layer between ectoderm and gastroderm. Ectoderm Endoderm
Phylum Cnidaria All cnidarians have stinging structures within their tentacles. Toxic substances paralyze prey. Mouth/anus leads to gastrovascular cavity. Where digestion, circulation and gas exchange occur.
Phylum Cnidaria Lifecycle alternates between asexual sessile polyps and sexual free-swimming medusas.
Phylum Cnidaria Portuguese Man-of-War Tentacles may be up to 55 m in length.
Annelida and Mollusca
Body Plan Exhibits bilateral symmetry. Each half is a mirror image of the other. Dorsal: Ventral: FRONT BACK
Body Plan Cephalization (Position of nervous structures). Sense organs and nerve cells concentrate at anterior end. Bilaterally symmetrical animals move through environment with anterior end forward. Coelom (fluid-filled body cavity). Ectoderm Mesoderm Coelom Endoderm
Phylum Annelida “Segmented Worms” Live in marine, freshwater and terrestrial environments. Segmented bodies and a coelom. Segmentation allows for larger growth and enhanced locomotion.
Phylum Mollusca “Animals with a Shell” Includes snails, slugs, clams, squids and octopuses. Moist, muscular body without a skeleton.
All Mollusks Have a… –Complete digestive tract –Body cavity (coelom) –Bilateral symmetry for at least part of their lives They have primitive brains and can sense their environment using sense organs located on top of their head.
Phylum Mollusca Body Plan 1. Locomotion and feeding. 2. Tissue that covers gills and secretes shell. 3. Internal Organs. Muscular Foot Mantle Visceral mass
Phylum Mollusca Class Bivalva Includes clams, oysters, scallops, mussels and other shellfish. Flexible hinge connects two shells. Have no head They don’t move much Filter feed
Phylum Mollusca Class Gastropoda Includes snails and slugs. Use foot for locomotion. Respiration through gills and moist skin. Name means “stomach footed”
Phylum Mollusca Class Cephalopoda Includes squids, octopuses and nautilus. Shell reduced to an internal rod. –Improves movement. Cephalopoda means ‘head footed’ Most complex mollusks Arms with suckers Sexual reproduction
Phylum Echinodermata “Radially Symmetrical Marine Animals” Includes sea stars, sea urchins, sand dollars and sea cucumbers. Larvae: Adults: Have an endoskeleton (internal skeleton) with spiny projections. Water vascular system: Bilateral Symmetry Radial Symmetry (5 similar body segments = pentamerous)
Phylum Echinodermata
Phylum Arthropoda “Animals with an Exoskeleton” 1, 170, 000 species (mostly insects). Segmented bodies, exoskeleton (external skeleton), jointed legs and blood cavity. Exoskeleton composed of chitin: Non-Living Material Jointed Appendages Outside skeleton protects muscles, organs and blood vessels.
Joint-Legged Animals
Phylum Arthropoda As arthropods grow, they molt or shed exoskeleton and grow a new one. Gills evolved in aquatic arthropods. Tracheae developed in terrestrial arthropods. Open circulatory system. Blood cavity directly bathes internal organs. Respiration Circulation
Nervous System: Simple to complex Digestive System made of three parts: –Foregut – mouth to esophagus –Midgut - stomach –Hindgut – intestine to anus Reproduction:Sexual
Phylum Arthropoda Class Arachnida Includes scorpions, spiders, mites and ticks. Cephalothorax: head fuses to thorax. 6 pairs of legs
Phylum Arthropoda Class Crustacea Includes shrimp, lobsters, crayfish and crabs. Three body segments: Head, Thorax and Abdomen Paired appendages attach to each segment. Two pair of antennae Three pair of feeding appendages Respiration: Gills
Phylum Arthropoda Class Insecta 1.5 million species. Three body segments: Head, Thorax and Abdomen Antennae on head sense environment. Three pairs of walking legs on thorax. May be one or two pairs of wings Respiration: Air sacs and trachea that extend from external openings to tissues.
Phylum Arthropoda Flying Insects: Two pairs of stiff wings attached to thorax. Flies: One pair of wings. Beetles: Front wings form hardened wing covers.
Phylum Arthropoda
Your Work… For each phylum we have learnt about, describe how there structure is adapted to its habitat (Hint: pg 416, 427, 441) What main characteristics are used to classify animals into different phyla? Turn to pg 441. Do the classifying Invertebrates activity. Turn to pg 445. Do question 25 Tomorrow we will be in RM 514