Dearolf
BIOL 220
NAME:________________________________________
WORKSHEET #1: INTEGUMENTARY SYSTEMS (CHAPTER 29)
1. Define an organ (Table 9.1, page 183). Why is integument considered an organ
(page 631)?
2. In addition to skin, name three other structures that can be part of an organism’s
integument (page 631).
3. Do sponges have an integument? (Characteristics of Phylum Porifera, page 247)
Why or why not?
4. Flatworms (Phylum Platyhelminthes) possess an integument, but the composition
of this organ varies in the different classes. Describe the integument of the
members of Class Turbellaria (turbellarians) and compare this integument to those
of the members of the three parasitic classes (page 292).
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Dearolf
BIOL 220
NAME:________________________________________
5. Molluscs possess an integumentary system. Describe the epidermis of these
organisms (Characteristics of Phylum Mollusca, page 332). In many groups of
molluscs (bivalves, gastropods, nautiloids), the epidermis of the mantle (pair of
folds formed by the dorsal body wall) is responsible for secreting a distinctive
structure. Name it (page 333).
6. The integumentary systems of the three parasitic classes of flatworms (question 4)
are very similar to the system of nematodes (roundworms). How are these systems
similar (page 384)?
7. Very briefly, describe the integument of arthropods (page 631).
8. Arthropods (page 631) and nematodes (page 384) share a characteristic. Name it.
Hint: the shared characteristic places them in Clade Ecdysozoa (page 383).
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Dearolf
9.
BIOL 220
NAME:________________________________________
Briefly describe the integument of vertebrates (page 631).
10. Draw the cladogram depicting the relationships between the major groups of
animals that was presented in lecture below. Indicate on your cladogram at which
point in the evolutionary history of animals integument (organ) appeared.
Similarly, indicate on the cladogram at which point integumentary systems (organ
system) appeared. Do any other characteristics of the integument, presented in the
questions above, appear to map on to the cladogram? If so, indicate the
characteristic on your cladogram.
DUE AT THE BEGINNING OF LECTURE ON FRIDAY, SEPTEMBER 11TH!!
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