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DNA sequencing is often performed to help produce phylogenetic trees or to classify organisms - VCE - SSCE Biology - Question 6 - 2010 - Paper 1
Question 6
DNA sequencing is often performed to help produce phylogenetic trees or to classify organisms. Sections of nuclear DNA from similar organisms are sequenced and compa... show full transcript
Worked Solution & Example Answer:DNA sequencing is often performed to help produce phylogenetic trees or to classify organisms - VCE - SSCE Biology - Question 6 - 2010 - Paper 1
Step 1
a. Name and describe another DNA method that is used to determine how closely related two species are.
Answer
One such method is DNA barcoding. This technique uses a short genetic marker in an organism's DNA to distinguish it from others. The most commonly used region for animals is the mitochondrial gene cox1, which is effective for species identification and phylogenetic studies.
Step 2
b. How would the barcode database be used to identify the fish species that had been caught by the fishermen? Provide an example of a situation (other than illegal fishing) when humans would want to identify the fish species.
Answer
The barcode database could be used to match the DNA sequence obtained from the fish caught to the extensive records in the database. This would identify the species accurately. An example of another situation is when researchers are studying fish populations in a marine reserve to monitor biodiversity.
Step 3
Step 4
d. Why is it important to sequence multiple samples from the same species?
Answer
It is important to sequence multiple samples from the same species to ensure the accuracy of results and to identify variations that exist within a species, which can inform conservation efforts and ecological studies.