Animalia Kingdom Notes

Animal Evolution

• How are animals classified?

  • Tissue layers
  • Body cavities
  • Reproduction
  • Symmetry
  • Development
  • Anatomical features
  • Digestion

• Animal Evolution Cladogram Analysis:

  • According to the cladogram, protists are suspected to be the ancient common ancestor for all animals.
  • According to the cladogram, sponges are considered the "original" animal.

• Animal Symmetry

  • What is symmetry?
    • The similarity or balance among body structures of organisms.
  • Identify the three types of animal symmetry.
    • Asymmetry
    • Radial Symmetry
    • Bilateral Symmetry

• Types of Symmetry:

  • Asymmetry: Body cannot be divided into even halves.
  • Radial Symmetry: Evenly divided halves radiating from a central point. Oral Surface: Surface with mouth. Aboral Surface: Opposite of mouth.
  • Bilateral Symmetry: Body can be divided into mirror image halves.
    • Annelids, or segmented worms, are most closely related to arthropods.

• Symmetry Identification:

  • Human: B (Bilateral)
  • Butterfly: B (Bilateral)
  • Sand dollar: R (Radial)
  • Sea sponge: A (Asymmetrical)
  • Alligator: B (Bilateral)
  • Snail: B (Bilateral)
  • Spider: B (Bilateral)
  • Coral: R (Radial)
  • Starfish: R (Radial)

• Invertebrate Embryonic Development:

  • Echinoderms exhibit embryonic development most similarly to that of humans (a chordate).

• Terms of Direction:

  • Anterior
  • Posterior
  • Dorsal
  • Ventral

Kingdom Animalia Characteristics

• Characteristics that all animals share:
  • Number of Cells: Multicellular
  • Cell Type: Eukaryotic
  • Obtaining Nutrition: Heterotrophic
  • Ability to move
  • Cell Support: Cell membrane
  • Reproduction: Sexual & asexual

Animal Cell Structures

• Functions of some important animal cell structures.

Animal Organization

• Cells $\rightarrow$ Tissues $\rightarrow$ Organs $\rightarrow$ Organ Systems $\rightarrow$ Organisms
• 95% of all animals are invertebrates.

Endoskeletons vs. Exoskeletons

• Exoskeletons:
  • Tough outer covering
  • Provide protection
  • Prevent water loss
  • Must be shed as it grows
  • Invertebrates
• Endoskeletons:
  • Internal framework of support
  • Vertebrates, endoskeleton with backbone

Animal Habitats

• Where in the world can animals be found?
  • Marine waters
  • Freshwater
  • Terrestrial
  • & More!

Animal Reproduction

• Most animals reproduce sexually.
• Examples of asexual reproduction in animals:
  • Fragmentation
  • Budding
  • Regeneration
• Earthworms are hermaphrodites.
• Internal Fertilization:
  • Sperm & egg join as a zygote inside animal's body.
• External Fertilization:
  • Sperm & egg form zygote outside of the body.

Animal Development

• Early Animal Development:

  • Sperm fertilizes egg leading to cell stage, then 2-cell stage, blastula, and gastrula.

• Gastrula Tissue Layers:

  • Endoderm: (innermost layer)
  • Ectoderm: (outermost layer)
  • Mesoderm: (middle layer) nourished by placenta