Notes 4.1
Simple Invertebrates

  Directions


  Review these notes. They are especially helpful when completing the notes self test and notes quiz. The notes open in a separate window which can be left open when you are working on the self test and quiz. You can resize the window by grabbing the bottom right corner and dragging it. You can also move the window by grabbing the top heading bar and dragging it. Be sure to close the extra window when you have finished using it.

  Introduction


Simple Invertebrates
  1. Invertebrates
  2. Sponges
  3. Stinging Celled Animals
  4. Comb Jellies
  5. Flatworms
  6. Roundworms

Top  Invertebrates

Common Characteristics of Invertebrates

    1. No backbone
    2. Multicellular
    3. Cells without cell walls
    4. Cells organized into tissues
    5. Specialized tissues for sex cell production

Top  Sponges

Phylum Porifera

    1. Animals with Pores
    2. Arranged around a series of canals
    3. Asymmetrical
    4. Endoskeleton of spicules and fibers
    5. No organs or organ systems

Top  Stinging Celled Animals

Phylum Cnidaria

    1. Stinging cells inject neurotoxin
    2. Radially symmetrical
    3. Sac-like body
    4. Gut cavity with one opening
    5. No circulatory system
    6. Polyp and medusa forms

Top  Comb Jellies

Phylum Ctenophora

    1. Eight rows of ciliary combs
    2. Radially symmetrical
    3. Medusa-like gelatinous body
    4. Gut cavity with one opening
    5. No circulatory system
    6. Some have sticky tentacles

Top  Flatworms

Phylum Platyhelminthes

    1. Body flattened
    2. Bilaterally symmetrical
    3. Branching gut with one opening
    4. No circulatory system
    5. Central nervous system and head
    6. Gliding motion

Top  Roundworms

Phylum Nematoda

    1. Slender, cylindrical body
    2. Bilaterally symmetrical
    3. Gut with two openings
    4. Whip-like motion
    5. Numerous in benthic sediments