Endosymbiosis WebQuest
Name
1. Search “evolution berkeley endosymbiosis” and click the link entitled, “It Takes Teamwork: How Endosymbiosis
Changed Life on Earth”
2. Begin your WebQuest/Case Study on the endosymbiont theory. Read through each page and analyze the
images. The goal of this webquest is to be able to answer the following 3 questions:
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What is endosymbiosis?
What role did endosymbiosis play in the evolution of eukaryotes?
How does endosymbiosis change our view of the branching pattern on the tree of life?
Answer the following questions as you proceed through the webquest.
1. List 3 kinds of symbioses. Next to each, provide an example of a symbiosis that you recall from earlier units.
2. Place a star next to the kind of symbiosis discussed in Kwang Jeon’s experiment.
3. It is theorized that a long ago in evolutionary history, two cells merged to form what?
4. What strong pieces of evidence support the idea that mitochondria used to be free-living organisms? Use your
own words to answer this question.
Why do you think a mitochondrion has 2 membranes?
5. What strong pieces of evidence support the idea that chloroplasts used to be free-living organisms? Use your
own words to answer this question.
Why do you think a cloroplast has 2 membranes?
6. Read the green box, “Weird Fact” on the right side of the page.
7. Analyze the cladogram at the bottom of the page. How does it compare to the cladogram of kingdoms you made
earlier? Explain.
8. Explain the tree and what it represents to someone who has not just finished a unit on evolution .
9. What is so interesting about mitochondrial DNA? Aside from reading the section on mitochondrial DNA, do a
search on what genes could be found on mitochondrial DNA.
10. Visit this page and read, to summarize the theory. http://learn.genetics.utah.edu/content/cells/organelles/
11. The goal of this webquest was to help you answer these three questions. Can you answer them?
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What is endosymbiosis?
What role did endosymbiosis play in the evolution of eukaryotes?
How does endosymbiosis change our view of the branching pattern on the tree of life?
12. Why have endosymbiosis and symbioses been so important to evolution? Answer in terms of natural selection
and evolution.
Learn better from the textbook?
Read Sections 26.3 and 26.4 to understand the evolution of eukaryotic cells from prokaryotes.