WLHS / AP BIO / Monson Name
POST-LAB ANALYSIS for AP INVESTIGATION #3:
Comparing DNA Sequences with BLAST
1) Begin with the Procedure on page S44 of your packet. Study the picture of the “Fossil Specimen” in Figure 3. Write down some observations about the morphology (physical structure) of this organism.
2) On page S45 in your lab packet, add a branch onto the cladogram in Figure 4 where you think this fossil might belong based on your initial observations.
3) Follow Steps 1-3 to download & save the gene files, and then upload them into BLAST. (NOTE: these files will NOT open your computer…just SAVE them to a location you can find when you get to BLAST and “BROWSE” for them)
4) For each of the gene sequences you run in BLAST, answer the following questions and think about your original hypothesis for this fossil specimen…do the BLAST data support or refute your original hypothesis?
GENE 1:
1) What species in the BLAST results has the most similar gene sequence to the gene of interest?
2) Where is that species located on your cladogram in relation to your predicted location for the fossil organism?
3) How similar is that gene sequence? (What percent similarity?)
4) What are the next 3 species with the most similar gene sequences to the gene of interest? (& how similar are their genes?)
scientific name: common name: % similar:
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GENE 2:
1) What species in the BLAST results has the most similar gene sequence to the gene of interest?
2) Where is that species located on your cladogram in relation to your predicted location for the fossil organism?
3) How similar is that gene sequence? (What percent similarity?)
4) What are the next 3 species with the most similar gene sequences to the gene of interest? (& how similar are their genes?)
scientific name: common name: % similar:
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GENE 3:
1) What species in the BLAST results has the most similar gene sequence to the gene of interest?
2) Where is that species located on your cladogram in relation to your predicted location for the fossil organism?
3) How similar is that gene sequence? (What percent similarity?)
4) What are the next 3 species with the most similar gene sequences to the gene of interest? (& how similar are their genes?)
scientific name: common name: % similar:
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GENE 4:
1) What species in the BLAST results has the most similar gene sequence to the gene of interest?
2) Where is that species located on your cladogram in relation to your predicted location for the fossil organism?
3) How similar is that gene sequence? (What percent similarity?)
4) What are the next 3 species with the most similar gene sequences to the gene of interest? (& how similar are their genes?)
scientific name: common name: % similar:
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Evaluating Results for PART 1:
On the main page of BLAST, click on the link “List All Genomic Databases.”
1) How many genomes are currently available for making comparisons using BLAST?
2) How does this limitation impact the proper analysis of the gene data used in this lab?
Designing & Conducting Your Investigation:
Follow the “Example Procedure” on page S49-S50 (STEPS 1-12) for the gene “human actin”. Once you feel comfortable with the program and the search tools, choose your own genes to investigate! Some suggested genes to explore are listed on page S50 of your lab packet. Time permitting, try to analyze 2 or more different genes. For each gene you analyze, answer the following questions:
GENE 1:
1) What is the function in humans of the protein produced from that gene?
2) Would you expect to find the same protein in other organisms? Why or why not? If so, which ones?
3) Is it possible to find the same gene in two different kinds of organisms but not find the pro tein that is produced from that gene?
4) If you found the same gene in all organisms you test, what does this suggest about the evolution of this gene in the history of life on earth?
5) What are top 4 species with the most similar gene sequence to the gene you chose? (& how similar are the genes?)
scientific name: common name: % similar:
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GENE 2:
1) What is the function in humans of the protein produced from that gene?
2) Would you expect to find the same protein in other organisms? Why or why not? If so, which ones?
3) Is it possible to find the same gene in two different kinds of organisms but not find the pro tein that is produced from that gene?
4) If you found the same gene in all organisms you test, what does this suggest about the evolution of this gene in the history of life on earth?
5) What are top 4 species with the most similar gene sequence to the gene you chose? (& how similar are the genes?)
scientific name: common name: % similar:
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GENE 3: (if time)
1) What is the function in humans of the protein produced from that gene?
2) Would you expect to find the same protein in other organisms? Why or why not? If so, which ones?
3) Is it possible to find the same gene in two different kinds of organisms but not find the pro tein that is produced from that gene?
4) If you found the same gene in all organisms you test, what does this suggest about the evolution of this gene in the history of life on earth?
5) What are top 4 species with the most similar gene sequence to the gene you chose? (& how similar are the genes?)
scientific name: common name: % similar:
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