1. Invertebrates

2. Animal Characteristics
All organisms in this kingdom have these common characteristics:
Multicellular Eukaryotes
No cell wall- unlike fungi, plants, bacteria
Heterotrophs– consumer not decomposer
Have Specialized Cells- unlike protists

3. Needs of Animals Need: Sense and chase down food source
Adaptation: nervous / motor systems
Need: Break up food and absorb nutrients
Adaptation: digestive system
Need: Deliver oxygen to all cells
Adaptation: circulatory / respiratory systems

4. SYMMETRY Asymmetry – no symmetry
Radial symmetry - can cut in equal halves-more than one way
Bilateral symmetry – allows for development of brain region in a central location (head)

5. Types of Symmetry
Asymmetry

6. Asymmetry-Sponges Only
                               
                                          
                                        

7. Radial Symmetry
                                                                                     

8. Background: different types of body symmetry
*Usually simpler organisms
*Usually more complicated organisms

9. Bilateral Symmetry
They all have a head
area with sense organs

10. Development of Organisms
Develop from a single cell, the zygote
Mitosis forms new cell in a process called cleavage
A hollow ball of cells are formed called a blastula
Gastrulation is the folding in of the blastula to form two layers
These two layers are the ectoderm and the endoderm

11. Development

12. Development Ectoderm develops into skin and nervous tissue
Endoderm develops into the lining of the digestive tract and organs associated with digestion
In some animals the gastrula forms a mesoderm
Mesoderm is the third layer and develops into muscles, circulatory, excretory, and respiratory systems

13. Development
Protostome is an animal with a mouth that develops from the opening in the gastrula called the blastopore
Deuterostome The anus develops from the opening in the gastrula

14. Body Plans
Acoelom- do not have a body cavity, organs are imbedded in tissues
Pseudocoelom -(partial) a body cavity partly lined with mesoderm
Coelom- a body cavity that provides space for the development of internal organs (something for muscles to push against to move)

15. *Background: types of coelomes (body cavities)

16. Vertebrate vs Invertebrate
Vertebrate- has a backbone
Invertebrate- has NO backbone

17. Exoskeleton Functions: Protection
Prevents water loss on land (waxy layer)
Problems:
Heavy
Growth requires molting

18. Exoskeletons

19. Endoskeleton
An internal skeleton that provides support inside the body
Advantage: Organisms can grow larger with skeleton inside

20. Endoskeletons

21. Sponges
Simplest Animals
Asymmetry

22. Sponges Sessile - do not move Asymmetrical
No tissue (Only organized cells)

23. Sponges Oxygen and food come in through Diffusion
Filter Feeds as an adult

24. Sponge Reproduction
Sexual – release sperm into water (external fertilization very common in aquatic animals)
Hermaphroditism – sponges have sperm AND eggs to increase the odds of reproduction
Offspring can swim to a new location
Asexual fragmentation also possible

25. Cnidarians
Sea Anemone
(Polyp)
Jellyfish (Medusa)

26. Cnidarians Evolution of Radial Symmetry
Extends tentacles equally in all directions
(increase food uptake)

27. Cnidarian Characteristics
Basic digestive system
Also basic nervous system (nerve net)
O2 still enters by diffusion

28. Cnidarian Characteristics
Reproduces sexually and asexually
Skeleton-none present, but dead coral remains are calcium carbonate

29. Body Plans of Cnidarians
                                     
                                 

30. Flatworms-Platyhelminthes
Planarian – not parasitic
Tapeworm – parasitic

31. Flatworm Characteristics
No coelom – Why? Many are parasitic
O2 and sugar are absorbed in host’s intestine
Bilateral symmetry
Reproduction-most are hermaphrodites

32. Tapeworms

33. Tapeworm Life Cycle

34. Uses Pharynx to obtain food
Flatworm or Planaria
                               
See full-size image.
Fresh Water Planaria
Uses Pharynx to obtain food
Salt Water Flatworms

35. Sheep Liver Fluke

36. Roundworms
hookworm - parasitic

37. Roundworms Smooth, non-segmented body Pseudocoelom (moves more)
Can burrow through skin (walking around barefoot)
Also enters through contaminated food

38. Roundworm Characteristics More Advanced
Bilateral symmetry
Complete digestive system with mouth and anus
Sexual reproduction
Oxygen enters by diffusion

39. Hookworms, Pinworms, Tapeworms that were removed from a Brazilian boy treated on a Rockefeller foundation mission (early 1900’s)
These parasites still affect people all over the globe.

40. Not a problem in U.S.

41. Why not? Food safety inspections Good sanitation
Medication widely available

42. Dirofilaria is a roundworm that causes heartworm disease in dogs.
Roundworms
Dirofilaria is a roundworm that causes heartworm disease in dogs.

43. Ascaris: a parasitic roundworm
Other Roundworms

44. The roundworm is carried by mosquitoes in tropical Africa
Other Roundworms
The roundworm is carried by mosquitoes in tropical Africa
Elephantiasis results when a roundworm blocks the lymphatic system, causing severe swelling

45. Roundworms: Hookworms
                              
Hookworms attached to
the intestines

46. Segmented Worms
Earthworm
leech

47. Segmented Worm Characteristics
Bilateral symmetry
Full Coelom (full range of motion, complex organs inside)
Complete digestion system
Most are hermaphrodites with sexual reproduction

48. Segmented Worm Characteristics
Gets O2 directly from moist skin,
closed circulatory system with hearts to deliver
Food – blood (leeches), or dirt (earthworms)

49. Earthworms
Giant Earthworm
Regular Earthworm

50. Earthworms Swallow dirt, filter out food
Loosen soil, helps to aerate soil for plants
Also fertilizes plants with castings (poop)

51. Leeches Two chemicals in saliva to help it take blood from hosts
Anesthetic (blocks pain)
Anti-coagulant (prevents blood clotting)

52. Mollusks
Squid – no shell
Snail – 1 shell
Clam – 2 shells

53. These are all in the same group!?!
inside of a clam

54. Mollusk Characteristics
Bilateral symmetry
Getting food – filter feeders (clams), grazers (snails), predators (slugs)
Getting O2 – gills in aquatic mollusks, primitive lung in snails
Open or closed circulatory system

55. Open vs. Closed Circulatory System
Blood in vessels
Larger animals
Open
No blood vessels
Blood surrounds body’s organs, delivers O2
Smaller animals

56. Mollusk Reproduction
Hermaphrodites (both mollusks and segmented worms)
Aquatic – release sperm and eggs into water
Land – meet and swap sperm, fertilize eggs inside

57. Chambered Nautilus

58. Arthropods Four main classes within this HUGE phylum: Arachnids
Crustaceans
Centipedes / millipedes
Insects

59. Arachnids
Chigger (flea)
Black widow
Brown recluse
Scorpion
Tick

60. Crustaceans
Crab
Lobster
Barnacles

61. Many-footed ones
Centipede
Millipede

62. Insects
Wasp
Fire ants
Grasshopper

63. Arthropod Characteristics
Most successful of all animal phyla
Coelom
Bilateral symmetry
Segmented body
Exoskeleton- NOT the same as mollusk shell

64. Arthropod Characteristics
Oxygen enters by spiracles and then into tracheal tubes in some arthropods. Book lungs in spiders.
Reproduction- Internal fertilization (mating) in land arthropods and External fertilization in sea arthropods

65. Arthropod Characteristics
Open circulatory system
Uses special jaws called mandibles
Use Pheromones (chemical signals) for communication and mating

66. Arthropods: Complex Nervous System
Sophisticated sensory / motor control
Compound eye of a fruit fly

67. Metamorphosis

68. Echinoderms
sea urchin
sea star
sea cucumber

69. Echinoderm Characteristics
Bilateral symmetry in larvae
Radial symmetry in adults (live on ocean floor)
Coelom
Endoskeleton
Deuterostomes

70. Echinoderm Characteristics
Food – variety of diet (some eat clams, some eat algae, some filter feed)
Water vascular system (water instead of blood to carry O2)
Reproduction typical in water
Regeneration possible in some

71. Chordates

72. All Chordates
Have notochord – precursor to vertebral spinal column (semirigid, filled with fluid)
Vertebrates replace this with a full spinal cord
Some chordates are invertebrates still

73. Chordates
Chordates have 3 subphylums
Tunicates
Lanceletes
Vertebrates

74. Invertebrate Chordates
tunicate
lancelet

75. Each of these is a Class in the Phylum Chordata