Photo AI
RFLP (Restriction Fragment Length Polymorphism) analysis is commonly used to determine genetic variation between individuals - VCE - SSCE Biology - Question 6 - 2008 - Paper 1
Question 6
RFLP (Restriction Fragment Length Polymorphism) analysis is commonly used to determine genetic variation between individuals. The procedure is summarised below. DNA... show full transcript
Worked Solution & Example Answer:RFLP (Restriction Fragment Length Polymorphism) analysis is commonly used to determine genetic variation between individuals - VCE - SSCE Biology - Question 6 - 2008 - Paper 1
Step 1
Explain the reason for their choice.
Answer
The reason for selecting a particular restriction enzyme is to ensure that it cuts the DNA at specific sites, which results in DNA fragments of varying lengths. The choice of enzyme is crucial because it determines the pattern of fragments generated. A suitable enzyme is selected based on factors such as the recognition sequence it requires and its ability to generate distinct fragment lengths for the individuals being analyzed.
Step 2
Describe one characteristic of this sorting process.
Answer
One characteristic of the sorting process during electrophoresis is that the DNA fragments are separated based on their size. Smaller fragments migrate faster through the gel matrix, allowing for the sorting of fragments; thus, creating a pattern that can be analyzed.
Step 3
Explain why the DNA of each individual produces a different pattern of fragments after gel electrophoresis, even when the same restriction enzyme is used.
Answer
Although the same restriction enzyme is used, the DNA of each individual may contain different sequences of nucleotides. Variations such as single nucleotide polymorphisms (SNPs) or insertions/deletions (indels) can lead to differences in where the enzyme cuts the DNA. As a result, the lengths of the resulting fragments will differ among individuals, producing distinct patterns in the gel.
Step 4
Describe, at the molecular level, what is meant by the term 'hybridised'. Why is it necessary to carry out hybridisation?
Answer
At the molecular level, 'hybridised' refers to the process where single-stranded DNA or RNA probes bind to their complementary sequences on the DNA fragments. This is necessary to detect specific DNA sequences among the fragments transferred to the membrane, allowing for the visualization and analysis of genetic variations.