1. State Three Characteristics That All Animals Have In Common
Chapter 28 Reading Questions
Invertebrate Evolution
1. State three characteristics that all animals have in common. 1- multicellular 2- ingest food 3-diploid life cycle
2. Explain the colonial flagellate hypothesis about the origin of animals. They are decended from an ancestor that resembles a hollow spherical colony of flagellated cells. Individual cells became specialized for reproduction. Two tissue layers arose by invagination.
3. Describe the different types of symmetry. Asymmetrical- no particular body shape; Radially- organized circularly; Bilaterally- definite left and right half
4. What is the difference between coelomates, acoelomates, and psuedocoelomates? Psuedocoelomates- body cavity between the digestive tract and body …show more content…
What features make sponges difference from the other organisms placed in the animal kingdom? Only animal that lacks true tissues to have a cellular level of organization.
6. What are choanocytes and what is their function in sponges? Cells that resemble a choanoflagellate. The beating of the flagella produces water currents that flow through the pores into the central cavity and out through the osculum.
7. In what ways are cnidarians more complex than the sponges Sponges are multicellular; no symmetry; no digestive cavity. Cnidarians have true tissues; radial symmetry; have a gastrovascular cavity.
8. What two body forms are found in cnidarians? Explain how they function in the life cycle of various types of cnidarians. Which one is the primary stage in jelly fish? Polypoid and medusoid. Polypoid- one side faces up while the other is connected to others of same species. Medusoid- upside down with mouth down. Medusoid.
9. Describe the anatomy of a free-living planarian, and how it differs from the parasitic flatworms. Pharynx, excretory system (flame cell), bilateral symmetry
10. How can we get tapeworms? After a pig eats feces-contaminated food, the larvae are released. They burrow through the intestinal wall and travel in the bloodstream and lodge in the
Invertebrate Evolution
1. State three characteristics that all animals have in common. 1- multicellular 2- ingest food 3-diploid life cycle
2. Explain the colonial flagellate hypothesis about the origin of animals. They are decended from an ancestor that resembles a hollow spherical colony of flagellated cells. Individual cells became specialized for reproduction. Two tissue layers arose by invagination.
3. Describe the different types of symmetry. Asymmetrical- no particular body shape; Radially- organized circularly; Bilaterally- definite left and right half
4. What is the difference between coelomates, acoelomates, and psuedocoelomates? Psuedocoelomates- body cavity between the digestive tract and body …show more content…
What features make sponges difference from the other organisms placed in the animal kingdom? Only animal that lacks true tissues to have a cellular level of organization.
6. What are choanocytes and what is their function in sponges? Cells that resemble a choanoflagellate. The beating of the flagella produces water currents that flow through the pores into the central cavity and out through the osculum.
7. In what ways are cnidarians more complex than the sponges Sponges are multicellular; no symmetry; no digestive cavity. Cnidarians have true tissues; radial symmetry; have a gastrovascular cavity.
8. What two body forms are found in cnidarians? Explain how they function in the life cycle of various types of cnidarians. Which one is the primary stage in jelly fish? Polypoid and medusoid. Polypoid- one side faces up while the other is connected to others of same species. Medusoid- upside down with mouth down. Medusoid.
9. Describe the anatomy of a free-living planarian, and how it differs from the parasitic flatworms. Pharynx, excretory system (flame cell), bilateral symmetry
10. How can we get tapeworms? After a pig eats feces-contaminated food, the larvae are released. They burrow through the intestinal wall and travel in the bloodstream and lodge in the