Dearolf
BIOL 220
NAME:________________________________________
WORKSHEET #3: DIGESTIVE SYSTEMS (CHAPTER 32)
1. Define intracellular digestion (page 698).
2. In which organisms is digestion completely intracellular (page 698)?
3. Identify two limitations to intracellular digestion (page 698).
4. Define extracellular digestion and name the system in which it occurs (page 698).
5. List two example groups of organisms that utilize intracellular and extracellular
digestion (page 698).
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Dearolf
BIOL 220
NAME:________________________________________
6. Name two groups in which digestion is almost completely extracellular (page 698).
7. Cnidarians and flatworms have incomplete digestive systems. These systems are
referred to as gastrovascular cavities. Define gastrovascular cavity (page G-14).
8. Most other multicellular animals have complete digestive systems. How does a
complete digestive system differ from an incomplete one (page 188)?
9. Alimentary canals can be divided into six major regions. NAME the six regions, and
compare the digestive system of an insect to that of a vertebrate by identifying the
organs that make up each of the six regions in BOTH (Figure 32.9, page 699).
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Dearolf
BIOL 220
NAME:________________________________________
10. Cnidarians are only at the tissue level of organization, so they cannot have a true
digestive system. However, their “digestive system” is similar in form to some other
genera that do have digestive systems. The term that is applied to this type of
digestive system is incomplete. Indicate on the cladogram which protostome and
deuterostome phyla exhibit incomplete AND complete digestive systems by placing
the appropriate term on each of their branches, as I have done for the Phylum
Cnidaria. Finally, place the characteristic Digestive System (organ system) on the
cladogram below.
Incomplete
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Dearolf
BIOL 220
NAME:________________________________________
DUE AT THE BEGINNING OF LECTURE ON WEDNESDAY, SEPTEMBER 16TH!!
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