1. Introduction to animals Introduction to Animals

2. Traits

3. Characteristics of Animals All multicellular (metazoans) Eukaryotes (cells with nucleus & organelles) Ingestive heterotrophs (take in food and internally digest it) Store food reserves in the liver as glycogen

4. Lions Feeding (Ingestion)

5. Body Symmetry

6. Bilateral symmetry occurs when animals can be divided into equal halves along a single plane Organisms will have right and left sides that are mirror images of each other More complex type of symmetry

7. Support Systems Have some type of skeletal support Endoskeleton inside and made of cartilage &/or bone Exoskeletons found in arthropods –Cover the outside of the body –Limit size –Must be molted making animal vulnerable to predators

8. Cicada Molting Exoskeleton

9. Support Systems Worms and echinoderms (starfish) have fluid-filled internal cavities giving them support Called hydrostatic skeletons

10. Coelom - Body Cavity Internal body cavity fully lined with mesoderm Body organs suspended in this cavity

11. Coelom - Body Cavity Acoelomate animals have solid bodies filled with cells Acoelomate animals include sponges, cnidarians, & flatworms

12. Germ Layers Form tissues, organs, & systems NOT present in sponges Ectoderm (outer) – forms skin, nerves, sense organs Endoderm (inner) – forms liver and lungs Mesoderm (middle) – forms muscles & other systems

13. Body Layers Sponges have NO tissues or organs, only specialized cells Cnidarians like jellyfish & coral have only two body layers & one body opening (mouth/anus) into gastrovascular cavity Cnidarians have outer epidermis & inner gastrodermis with jelly- like mesoglea between the layers

14. Movement Animals such as sponges may be sessile (attached & non-moving) Animals that move very little are said to be sedentary (clam) Animals that can move are motile Have muscular tissue to provide energy for movement

15. SESSILESEDENTARY MOTILE Sponge Chiton Cheetah

16. Reproduction in Animals All animals are capable of sexual reproduction Some animals like sponges and earthworms are hermaphrodites producing both eggs and sperm Hermaphrodites may exchange sperm and NOT fertilize their own eggs

17. Leeches Exchange Sperm During Mating Mating leech

18. Reproduction in Animals Females of some animals produce eggs, but the eggs develop without being fertilized Called Parthenogenesis New offspring will be all female Parthenogenesis occurs in some fishes, several kinds of insects, and a few species of frogs and lizards

19. Parthenogenesis in the Komodo Dragon

20. Mating and Mating Behaviors Beetles Mating Male Female Young Courtship

21. Levels of Organization Sponges are the ONLY animals that have just the cellular level All other animals show these levels – cell, tissue, organ, and system Cells may specialize (take own different shapes and functions) Cells are held together by cell junctions to form tissues

22. Atom Molecule or compound Organelle CELL Levels of Organization Tissue Organ Organ system Organism Life begins

23. Invertebrate groups

24. Characteristics of Invertebrates Simplest animals Contain the greatest number of different species Most are aquatic (found in water) Do NOT have a backbone Includes sponges, cnidarians, flatworms, roundworms, annelids, mollusks, arthropods, and echinoderms

25. Sponge - Porifera Osculum of Sponge

26. Sea Anemone - Cnidaria Tentacles of Sea Anemone

27. More Cnidarians Brain Coral Red jellyfish

28. Flatworms - Platyhelminthes Planarian Marine Flatworm

29. Roundworms (Nematoda) and Segmented Worms (Annelida) Nematode Leech (segmented worm)

30. Mollusca (With and Without Shells) snailscallop nautilus nudibranch octopus

31. Arthropoda (insects, spiders, crustaceans, horseshoe crab) Dung beetle Horseshoe crab crayfish spider

32. Echinoderms Sea cucumber Sand dollar starfish Brittle star Sea fan (crinoid)

33. Vertebrate Groups

34. Vertebrata More complex animals Most have a backbone made up of individual bones called vertebrae From simplest to most complex, the phylum includes: fish, amphibians, reptiles, birds, and mammals

35. Vertebrate Backbone

36. Vertebrata Vertebrates have endoskeletons (internal) Some vertebrates have skeletons of cartilage (sharks, rays, and skates) Other vertebrates have skeletons of bone and cartilage (reptiles, birds, & mammals)

37. Bone & Cartilage in Fetus

38. Fish lancelet ray anglerfish damselfish

39. Amphibia toad newt frog salamander

40. Reptilia Turtle Snake Alligator Lizard

41. Birds - Aves hummingbird ostrich lovebirds

42. Mammalia

43. Body Areas

44. Surfaces Dorsal – back or upper surface Ventral – belly or lower surface Anterior – head or front end Posterior – tail or hind end opposite the head Oral surface (echinoderms) – is where the mouth is located (underside) Aboral surface (echinoderms) – is opposite the mouth (top side)

45. DORSAL VENTRAL Surfaces (Most Animals) ANTERIOR POSTERIOR

46. Surfaces (Echinoderms) ORAL ABORAL mouth

47. Segmentation

48. Segmentation Occurs whenever animal bodies are divided into repeating units or segments Found in more complex animals Earthworms show external segmentation Humans show internal segmentation (backbone) Segments may fuse (cephalothorax)

49. Segmentation cephalothorax

50. Tissues

51. Tissue Development Zygote (fertilized egg) undergoes rapid cell divisions called cleavage Forms a hollow ball of cells called the blastula

52. Blastula The blastocoel is the center cavity of the blastula with 1 germ layer (blastoderm)

53. Tissue Development The blastula INVAGINATES (folds inward at one point) Called Gastrulation The opening is called the blastopore The center is the primitive gut or Archenteron blastopore Archenteron

54. Embryonic Development

55. Germ Layers Form tissues, organs, & systems NOT present in sponges Ectoderm (outer) – forms skin, nerves, sense organs Endoderm (inner) – forms liver and lungs Mesoderm (middle) – forms muscles & other systems

56. Body Layers Sponges have NO tissues or organs, only specialized cells Cnidarians like jellyfish & coral have only two body layers & one body opening (mouth/anus) into gastrovascular cavity Cnidarians have outer epidermis & inner gastrodermis with jelly- like mesoglea between the layers

58. Body Layers All worms, mollusks, arthropods, echinoderms, and vertebrates have three cell layers –Ectoderm –Endoderm –mesoderm

59. Stages of Development

60. Larval Forms Animals with Indirect development Go through immature (larval) forms Larva does NOT resemble adult Cnidarian (jellyfish, coral, & sea anemone) larva called Planula

61. Larval Forms Mollusk (squid & octopus) larva called trochophore Echinoderm (starfish) larva is called Dipleurula

62. Metamorphosis Usually found in arthropods May be complete or incomplete Incomplete Metamorphosis: egg nymph adult Complete Metamorphosis: egg larva pupa adult

63. Metamorphosis COMPLETE INCOMPLETE

64. Animal Systems

65. Support Systems Spongin & spicules (sponges) Limestone cases (corals) Exoskeletons of Chitin (arthropods) –Must be shed or molted to grow Inner Calcium plates or Test (echinoderms) Bone/cartilage endoskeleton (vertebrates)

66. Digestive Systems All animals are ingestive heterotrophs Choanocytes (specialized cells) capture & digest food for sponges Gastrovascular cavity with one opening in cnidarians and flatworms for food to enter & leave; called two-way digestive system

67. Two-Way Digestion

68. Digestive Systems Animals with a one-way digestive system have a mouth and an anus Food enters the mouth, continues in one direction through the digestive tract, and wastes leave through the anus Includes annelids, arthropods, & vertebrates

69. One-Way Digestion Mouth anus

70. Circulatory Systems Transports oxygen & nutrients to cells Carries away wastes & carbon dioxide from cells Sponges, cnidarians, & flatworms do NOT have circulatory systems

71. Circulatory Systems In closed circulation, blood remains inside blood vessels until it reaches cells (annelids & vertebrates) In open circulation, blood is pumped out of blood vessels to bathe tissues in the body cavity or hemocoel (arthropods & mollusks)

72. Open Circulation Closed Circulation