The Animal Kingdom

1. The Animal Kingdom Overview Zoology

2. Phylum Porifera • Sponges • General Characteristics • All aquatic (generally marine) • Multicellular • No tissues or organs • Asymmetrical or radial symmetry • Filter feeders • Pore and water canal systems • Asexual and sexual reproduction • Central cavity and/or a series of branching chambers • Sessile adult (attached to one spot) • Free-swimming larval stage • Internal skeletons • Spicules or spongin

3. Phylum Porifera • Commercial uses • Sponges • Medicinal • Produce antimicrobial compounds • Produce anti-cancer agents • Other • Food and cover for other marine organisms • Have beneficial relationship (called commensalism) with bacteria, algae, and plantlike protists. • This relationship allows them to live in a variety of habitats. • Sponges containing photosynthetic organisms play an important role in coral reefs. • Sponges on the sea floor have spicules that focus sunlight and allow organisms living below the surface to carry out photosynthesis • Provide habitats for other organisms like shrimp, worms, snails and crabs.

4. Phylum Cnidaria • General Characteristics • All aquatic (most marine) • Radial symmetry • Cell organized into tissues – two true tissues, no organs • Diploblastic • Only one opening • Cnidocytes –stinging cells • Gastrovascular cavity • Central digestive compartment • Sessile (polyps) or free-floating (medusa) • Planular (free swimming) Larvae • Nerve cells organized into nerve net • Includes: Jellyfish, Hydras, Sea Anemone, and Coral

5. Phylum Platyhelminthes • No more than a few millimeters thick • Soft, flattened worms that have tissues and internal organs • Bilateral symmetry • Cephalization • Acoelomate – no body cavity • Rely on diffusion for essential body function (respiration, excretion, and circulation) • Free-living (Planarians) • Parasitic (Tapeworm)

6. Phylum Nematoda • Slender, unsegmented worms with tapering ends • Have pseudocoelom and digestive system with two openings -- a mouth and an anus • Range in size from microscopic to one meter in length! • Most are free-living and inhabit soil, salt flats, aquatic sediments, and water from polar regions to tropics • Some are parasitic and live in hosts that include almost every kind of plant and animal. • Develop from 3 germ layers but have a body cavity between endoderm and mesoderm • Called pseudocoelom because the body cavity is only partially lined with tissue derived from the mesoderm. • Called “tube-within-a-tube” because the inner tube is the digestive tract and the outer tube is the body wall. • Food moves in one direction from mouth to anus (posterior end of digestive tract)

7. Phylum Nematoda ORGANISM Trichinella Filiarial worms Ascaris Hookworms DISEASE Trichinosis Elephantiasis Ascaris infection/infestation Hookworm infection/infestation ROUTE OF INFECTION Eating undercooked meat containing larval cysts Bite of insect carrying filarial worms Eating unwashedfood contaminatedwith Ascaris Bare skin in contact with contaminated soil DESCRIPTION Larvae burrow into tissues of host, causing pain Worms block passage of fluids within lymph vessels, causing tissues to swell Worms in intestine block normal passage of food and absorption of nutrients Worms attach to intestinal wall and suck blood, causing weakness and poor growth

8. Phylum Annelida • Worms with segmented bodies. • Specialized segments contain sense organs, and carry out respiration • Separated by septa • Bristles called setae attached to each segment • Oligochaeta– earthworms • Hirudinea– leeches • Polychaeta– polychaetes (sandworms, bloodworms)

9. Phylum Mollusca • Soft-bodied animals that have an internal and external shell. • There are over 150,000 species of mollusks. • Includes snails, slugs, clams, squids, and octopi. • Grouped in the same phylum because they have similar developmental stages. • Free-swimming larval stage: trocophore.

10. Phylum Mollusca

11. Phylum Echinodermata • Echinoderms are marine animals that are often found attached to rocks. • Echinoderm means ‘spiny skin’ and includes sea stars, brittle stars, featherstars, sea urchins, sand dollars, and sea cucumbers. • Echinoderms are characterized by a water vascular system with tube feet and radial symmetry.

12. Phylum Arthropoda • Three distinguishing features: • 1) Segmented Body • 2) Tough Exoskeleton – made from chitin, protects and supports the body. • 3) Jointed Appendages – structures such as legs and antennae that extend from the body wall • Named for jointed appendages – arthron means “joint” in Greek • Arthropods are classified based on the number and structure of their body segments and appendages, mainly their mouthparts. • Three major groups: • 1) Crustaceans (lobsters, crabs, crayfish, barnacles) • 2) Arachnids (spiders, mites, ticks, scorpions) • 3) Insects and their relatives (fly, butterfly, bee) (millipedes, centipedes)

13. Vertebrates • Phylum: Chordata • There are 4 key characteristics that must be present at some stage in a chordates life cycle: • Dorsal, hollow nerve cord • Notochord • Pharyngeal Pouches • A tail that extends beyond the anus • Subphylum: Vertebrata • Have a backbone • 5 Groups make up about 96% • Fishes • Amphibians • Reptiles • Birds • Mammals

14. Fish • Fish were the first vertebrates to evolve. • 2 Major Adaptations: • Jaws • Used to hold teeth and muscle • Defense mechanism • Paired Fins • Made of cartilage (flexible) • Allowed for more swift body movement • Approximately 24,000 living species. • Major Groups: • Jawless – no vertebrate, includes lampreys and hagfishes • Cartilaginous – Chondrichthyes, includes sharks, rays, skates, sawfish, and chimaeras • Bony – Osteichythes • Ray Finned – most fish • Lobe Finned – Lungfishes and Coelacanth

15. Amphibians • Word Amphibian means “Double Life” • Vertebrates • Tetrapods • Class: Amphibia • Live in water and on land • Generally in water as larva and on land as adults • Challenges of transitioning from water to land: • Needed legs to climb out of water • Needed some way to breathe air • Needed protection from drying out • Adaptations: • Bones in the limbs • Lungs and breathing tubes

16. Amphibians • Salamanders & Newts • Order: Urodela • 4 legs • Live in moist woods • Frogs & Toads • Order: Anura • 4 legs adapted for jumping • Closely tied to water • Caecillians • Order: Apoda • Legless animals • Live in water or burrow into soil • Amphibians are going extinct at a faster rate than any other group, mainly in the tropics. • Reasons • habitat loss, climate change, UV-B radiation, pollution, disease, overharvesting • Bioindicators • amphibians show how healthy or polluted a habitat is

17. Reptiles • Land vertebrate • Well-developed skull • Backbone and tail • 4 Limbs • Dry, scaly skin • Lungs • Terrestrial eggs • Ectotherms (cold-blooded) • Female’s reproductive system covers the embryos with membranes and a leathery shell • Most are oviparous or ovoviviparous • Shell and membrane of reptilian eggs protect the embryo from drying out • Amniotic Egg – 4 membranes (amnion, yolk sac, chorion, and allantois)

18. Reptiles • Lizards and Snakes • Order: Squamata • Scaly Reptiles • Crocodilians • Order: Crocodilia • Includes alligators, crocodiles, caimans, and gavials • Turtles and Tortoises • Order: Testudines • Turtle refers to members that live in water • Tortoise refers to members that live on land • Tuataras • Order: Sphenodonta • Only found on a few islands off the coast of New Zealand

19. Reptiles

20. Birds • Reptile-like animals • Warm-blooded (maintain constant internal body temperature) • Outer covering with feathers • 2 legs covered with scales and used for walking or perching • Front limbs are modified into wings • Feathers • Assist in flight • Help keep birds warm • 2 Types: • Contour – lifting force needed for flight • Down – trap air close to the body, for warmth

21. Mammals • Class: Mammalia • 2 Key Features • Hair - warmth • Mammary Glands – produce milk for young • Breathe Air • Have 4-chambered hearts • Endotherms: generate and conserve body heat • Reproduction • Mammals give birth in 3 ways: • Placental mammals give birth to live young • Monotremes lay eggs • Marsupials bear live young that live in an external pouch