Site MapHelpFeedbackeLearning
eLearning
(See related pages)

ConceptsQuestionsMedia Resources
29.1 Evolution of animals
  • Animals are multicellular heterotrophs that move about and ingest their food. They have a diploid life cycle.
  • Animals are classified according to certain criteria, including type of coelom, symmetry, body plan, development, and presence of segmentation.
  1. What are the five criteria for classification of animals?
    Answer
  2. Define cephalization.
    Answer
  3. What is a true coelom?
    Answer
  4. An animal is a _____________ if the first opening that appears in the embryo becomes the mouth and a _______________ if the first opening becomes the anus.
    Answer
  5. What characteristic of animals can lead to specialized body parts?
    Answer
 Essential Study Partner Summaries of major points:
  1. Animals are multicellular eukaryotes
  2. Classification criteria
Art Quizzes Animation Quizzes
29.2 Multicellularity
  • Sponges have the cellular level of organization and lack tissues and symmetry. They depend on a flow of water through the body to acquire food.
  1. What characteristics of sponges make them the only group of animals with a cellular level of organization?
    Answer
  2. How do sponges obtain food?
    Answer
  3. Because sponges are attached to the substrate, they can't move to a new location. How do they disperse?
    Answer
  4. What makes up the 'skeleton' of sponges?
    Answer
Essential Study Partner Summaries of major points:
  1. About 5,000 species of sponges are in the phylum Porifera
Art Review
29.3 Two tissue layers
  • Cnidarians and comb jellies have a radially symmetrical saclike body consisting of two tissue layers derived from the germ layers ectoderm and endoderm.
  • Cnidarians typically are either polyps (e.g., Hydra) or medusa (e.g., jellyfishes) or alternate between these two forms, the polyp being an asexual state and the medusa being a sexual state.
  1. What is the difference between animals with radial symmetry and those with bilateral symmetry?
    Answer
  2. Which two phyla of animals have only two tissue layers and what are those layers?
    Answer
  3. What is contained in a cnidocyte and what does it do?
    Answer
  4. What is a dimorphic cnidarian?
    Answer
  5. What type of cnidarian is responsible for the production of limestone like reefs?
    Answer
  6. Most cnidarians and ctenophores filter food from the water using _____________.
    Answer
 Essential Study Partner Summaries of major points:
  1. About 90 species of comb jellies are in the phylum Ctenophora
  2. Cnidarians
  3. Cnidarian diversity
  4. Hydra and Obelia
Art Review Art Quizzes
29.4 Bilateral symmetry
  • Ribbon worms and flatworms have tissues and organs derived also from mesoderm, the third germ layer. They have the organ level of organization and are bilaterally symmetrical.
  • Planarians are free-living predators, but flukes and tapeworms are animals adapted to a parasitic way of life.
  1. What is the difference between the "sac" and "tube-within-a-tube" body plans?
    Answer
  2. Animals with both male and female organs are called ____________.
    Answer
  3. What adaptations do trematodes and cestodes exhibit which allow them to be parasitic?
    Answer
 Essential Study Partner Summaries of major points:
  1. Triploblasts
  2. About 650 species of marine ribbon worms are in phylum Nemertea
  3. Flatworms
  4. Planarians
  5. Parasitic flat worms
  6. Flukes
  7. Tapeworms
Art Review Art Quizzes
29.5 A pseudocoelom
  • Roundworms and rotifers have a coelom, a body cavity where organs are found and that can serve as a hydrostatic skeleton. Their coelom is a pseudocoelom because it is not completely lined by mesoderm.
  • Round worms take their name from a lack of segmentation; they are very diverse and include some well-known parasites.
  1. What is a pseudocoelom?
    Answer
  2. What two phyla of animals have pseudocoeloms?
    Answer
 Essential Study Partner Summaries of major points:
  1. Roundworms
  2. Rotifers
Art Review





To learn more about the book this website supports, please visit its Information Center.
(c)2004 McGraw-Hill Higher Education
Any use is subject to the Terms of Use and Privacy Policy.
McGraw-Hill Higher Education is one of the many fine businesses of The McGraw-Hill Companies.


BiologyOnline Learning Center with Powerweb

Home > Chapter 29 > eLearning