Photo AI
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
Name and describe another DNA method that is used to determine how closely related two species are.
Answer
One method used is Restriction Fragment Length Polymorphism (RFLP). This technique involves the extraction and digestion of DNA with specific restriction enzymes, which cut the DNA at predetermined sequences. The resulting fragments can then be separated through gel electrophoresis. By comparing the patterns of the fragments between species, scientists can infer phylogenetic relationships.
Step 2
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 can be employed to match genetic sequences from the fish caught with those stored in the database, allowing researchers to identify the fish species accurately. An example of another situation would be during biodiversity assessments, where scientists may want to catalog and study fish populations in a particular ecosystem.
Step 3
Explain what redundancy in the genetic code means.
Answer
Redundancy in the genetic code refers to the phenomenon where multiple codons can encode for the same amino acid. This means that although there are 64 possible codons, only 20 amino acids exist, resulting in some amino acids being represented by more than one codon.
Step 4
Why is it important to sequence multiple samples from the same species?
Answer
Sequencing multiple samples from the same species is crucial for ensuring the accuracy of results and identifying variations that may exist within that species. It helps to capture genetic diversity and provides a more comprehensive view of the species' genetic makeup.