Dearolf
Spring 2015
BIOL 440
QUESTIONS FOR VERTEBATE ORIGIN AND INTEGUMENT READINGS (PAGES
83-85; 212-216)
1. Why did scientists initially believe that vertebrates evolved in a freshwater
environment? Give two pieces of evidence that supported this evolutionary
hypothesis.
2. What new piece of evidence convinced scientists that vertebrates evolved in
a marine environment?
3. How were the old pieces of evidence (answer to question #1) reinterpreted
to support the hypothesis that vertebrates evolved in a marine environment?
4. What feature characterized the early evolution of vertebrates?
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Dearolf
Spring 2015
BIOL 440
5. Summarize the three major steps thought to describe the evolution of early
vertebrates.
6. What changes in the pharynx are hypothesized to have occurred during the
early evolution of vertebrates and why were these changes necessary?
7. The integument is a composite organ. Name the two layers that make it up
and the structure that separates these two layers.
8. The structure that separates the two layers is made up of components that
come from each of the two layers. Identify these components.
9. Identify the layer between the integument and the deep body musculature.
Which tissues make up this layer? What is this layer called in microscopic
examination? In gross anatomical dissection?
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Dearolf
Spring 2015
BIOL 440
10. Which structures are produced by the outermost layer of the integument?
11. Which structures are produced by the innermost layer of the integument?
12. Which structures are produced by both layers of the integument?
13. List five functions of the integument.
DUE IN LECTURE ON THURSDAY, JANUARY 29TH!
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