Chapter 32: Animal Diversity

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Chapter 32: Animal Diversity
2013-10-09 23:03:25

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  1. What are 3 general features of all animals?
    • Heterotrophic
    • Multicellular
    • No cell walls
  2. Name 3 things that some, but not all animals are capable of...
    • The ability to actively move
    • Sexual reproduction
    • Specialized tissues
  3. What does it mean for an animal to have specialized tissue?
    Muscles and nerve cells are central to the animal's lifestyle
  4. What are the 5 key innovations in animal evolution?
    • 1. Symmetry
    • 2. Tissues that allow for specialized structures/functions
    • 3. Body cavity
    • 4. Various patterns of embryonic development
    • 5. Segmentation or repeated body units
  5. Most animals exhibit ___ or ___ symmetry.
    Radial or bilateral
  6. Shape: Sponges are _____
  7. Radial symmetry:
    • longitudinal plane through the central axis divides the animal into two halves that are mirror images of each other.
    • Examples: members of phylum Cnideria
  8. Bilateral Symmetry:
    • Body has right and left halves that are mirror images of each other
    • Example: Most animals that are not sponges or Cnidarians
  9. What are some advantages of bilateral symmetry?
    • Move in a consistent direction with head end leading
    • Associated with brain, sensory structures such as eyes and ears (cephalization)
  10. Give an example of an animal type with radial symmetry:
    members of the phylum Cnidaria
  11. Give an example of an animal type with bilateral symmetry:
    Most animal that are not a sponge or cnidarian
  12. What is cephalization?
    Centralization of neural and sensory organs in the head or anterior region of the animal
  13. The evolution of tissues allowed for _____ and ___.
    Specialized structures and functions
  14. Zygotes are _____. They can give rise to any and all cells in the animals body.
    Totipotent--all powerful, cell fate not yet determined
  15. True or false: Cells specialize during embryonic development
  16. True or False: Specialization is irreversible in all animals.
    False! All animals, EXCEPT sponges.
  17. List the 4 steps of early embryonic development:
    • Cleavage
    • Blastula formation
    • Gastrula formation
    • Archenteron
  18. Cleavage:
    succession of mitotic cell divisions without cell growth between the divisions
  19. Blastula
    hollow ball of cells produced by cleavage; cavity inside is the blastocoel.
  20. Coel means what?
  21. Gastrula:
    formed from the blastula when one end of the embryo folds inward, expands, and fills the blasocoel.
  22. Archenteron:
    • pouch inside the gastrula
    • opens to the outside via the blastopore
  23. What made possible the development of advanced organ systems?
    A body cavity
  24. What are the 3 germ layers?
    • 1. Ectoderm (outer layer)
    • 2.¬†Mesoderm (middle layer)
    • 3. Endoderm (inner layer)
  25. The ectoderm layer gives rise to:
    • nervous system
    • outer covering of the body
  26. The mesoderm gives rise to:
    • Skeleton
    • Muscles
  27. The endoderm gives rise to:
    • digestive system, including intestines
    • organs like the liver
    • lungs of vertebrates
  28. Animals that have all three germ layers are ____.
    • triploblastic.
    • Also members of the bilateria
  29. Cnidarians have how many germ layers?
    • Only two germ layers
    • Ectoderm
    • Endoderm
  30. _____ are diploblastic, meaning they have no organs.
  31. True or false: Sponges have some tissues but no organs
    False! Sponges do not have any tissues or organs!
  32. Name the 3 body plans for bilaterally symmetrical animals (CAP):
    • 1. Coelomate
    • 2. Acoelomate
    • 3. Pseudocoelomate
  33. Coelomate:
    • Body cavity develops entirely within the mesoderm
    • Example: annelids, humans
  34. Acoelomate
    • No body cavity between digestive tract and muscle layer.
    • Example: flatworms
  35. Pseudocoelomate
    • Have body cavity that develops between mesoderm and endoderm
    • Example: Roundworms
  36. Which body plan for bilaterally symmetrical animals contains those with a body cavity between the medoderm and endoderm?
  37. The circulatory system functions to  carry ______ to tissues and removes ________, by diffusion between the circulatory fluid and other cells in the body.
    • nutrients and oxygen
    • wastes, including carbon dioxide
  38. Open circulatory system:
    blood passes from vessels into sinuses, mixes with body fluid that bathes the cells or tissues, and then re-enters vessels in another location.
  39. Closed circulatory system:
    Blood is entirely confined to vessels and is physically separated from other body fluids.
  40. Bilaterians have 2 main types of development:
    • 1. Protostome
    • 2. Deuterostome
  41. Protostome:
    • "First mouth"
    • Mouth develops from the blastopore
    • Example: flatworms, nematodes, mollusks, annelids, arthropods
  42. Deuterostome:
    • "second mouth"
    • anus develops from the blastopore
    • Examples: echinoderms (starfish, sea urchins) and chordaes (humans, animals with backbone)
  43. Chordates and echinoderms are (protostomes/deuterostomes).
  44. Archenenteron
    Primative gut
  45. Blastopore
    Opening into the archenteron
  46. Name the two types of cleavage patterns:
    • Spiral cleavage
    • Radial cleavage
  47. Spiral Cleavage:
    • New later of cells, nestles into the space between the older cells
    • Examples: annelids, mollusks, nemerteans, and other protosomes.
  48. Radial Cleavage:
    • pairs of new cells are positioned directly above the older cells
    • Example: All deuterostomes
  49. Protostomes have (determinate/indeterminate) development.
    Determinate development
  50. Deuterostomes have (determinate/indeterminate) development.
  51. Determinate development:
    • the type of tissue that each embryonic cell will form is determined early
    • Protostomes
  52. Indeterminate development
    Each cell remains totipotent and each cell's fate is not determined for several cleavages.
  53. What are the advantages of segmentation?
    • Efficient and flexible movement
    • Redundant organ systems
  54. There are _____ phyla based on shared characteristics. All animals share a common ancestor.
    35-40 phyla
  55. Metazoa class:
    includes the sponges that DO NOT have embryonic germ layers or differentiated cells that form tissues.
  56. Eumetazoa class:
    • includes animals that have embryonic germ layers and differentiated cells that form tissues.
    • Most animals
  57. What has helped reveal evolutionary relationships?
    Molecular data
  58. Morphology and molecule based phylogenies agree on many major groupings.
    • Sponges: monophyletic; shares common ancestor with other animals
    • Cnidarians: evolved before bilaterally symmetrical animals
    • Annelids and arthropods were thought to be closely-related based on segmentation, but the arthropods are now grouped with animals
  59. ____ evolved before bilaterally symmetrical animals
  60. ____ molt their cuticles at least once during their life.
  61. Morphology-based phylogeny focused on the state of the ____.
  62. The protostomes and deuterostomes differ in ______.
    Embryology (mouth or anus development)
  63. All acoelomates and pseudocoelomates are (deuterostomes/protostomes).
  64. True or Falsue: All coelomates deuterostomes.
    False. Some coelomates are protostomes (like earthworms) and some are deuterostomes (humans).
  65. Protostomes consist of what two subgroups?
    • Spiralians
    • Ecdysozoans
  66. Spiralian animals grow by:
    adding mass to the body and exhibit spiral cleavage
  67. Ecdysozoans grow by:
    • they grow by molting external skeletons.
    • nematodes and arthropods
  68. Annelids, mollusks, rotifers, platyhelminthine worms, ectoprocts, and brachiopods are _____
    Lophotrochozoa, spiralian animals (subgroup of protosomes)
  69. Helminthine means:
  70. Deuterostomes include:
    • Chordates
    • Echinoderms
    • Patterns of development indicate that echinoderms and chordates evolved from a common ancestor
  71. Metazoans appear to have evolved from colonial _____.
  72. The Eumentazoa most likely evolved from colonial _____.
  73. _____ analysis may explain the Cambrian explosion.
  74. Rapid diversification may be result of evolution of ______ genes.
    Hox genes.