DNA Profiling

Question 1

What is DNA profiling?

Answer 1

A technique used to identify individuals based on their unique DNA characteristics

DNA profiling is often used in forensic science, paternity testing, and genetic research.

Question 2

What are genetic markers in DNA profiling?

Answer 2

Short Tandem Repeats (STR)

STRs are specific sequences in DNA that are repeated multiple times and vary among individuals.

Question 3

Define DNA fingerprint.

Answer 3

A unique pattern of DNA fragments produced by gel electrophoresis

DNA fingerprints are used for comparison in forensic investigations.

Question 4

What is the purpose of purifying DNA?

Answer 4

To isolate DNA from other cellular components

This process typically involves breaking down cellular membranes and removing proteins.

Question 5

What is electrophoresis?

Answer 5

A method used to separate DNA fragments based on size

Gel electrophoresis utilizes an electric field to move negatively charged DNA fragments through a gel matrix.

Question 6

What role does the protease enzyme play in DNA extraction?

Answer 6

It removes the protein framework of chromosomes

This step is crucial for isolating pure DNA from cellular debris.

Question 7

What is PCR?

Answer 7

Polymerase Chain Reaction, a technique used to amplify DNA

PCR allows for the creation of millions of copies of a specific DNA segment.

Question 8

What genetic condition is associated with a faulty huntingtin gene?

Answer 8

Huntington’s disease

This condition is characterized by the production of too many CAG repeats in the huntingtin gene.

Question 9

What is the significance of CAG repeats in Huntington’s disease?

Answer 9

They lead to neuronal damage in specific brain areas

The exact mechanism of damage is still under investigation.

Question 10

How can DNA be used to confirm different species of grass snakes?

Answer 10

By comparing DNA patterns using gel electrophoresis

Differences in the banding patterns indicate distinct species.

Question 11

What is the first step in DNA extraction?

Answer 11

Breaking up the cells to expose DNA

This is typically done using physical methods and chemical agents like soap and salt.

Question 12

Fill in the blank: The addition of _______ helps DNA to precipitate during extraction.

Answer 12

ethanol

Question 13

True or False: Shorter DNA fragments move faster than longer fragments in gel electrophoresis.

Answer 13

True

Question 14

List three uses of gel electrophoresis.

Answer 14

• Criminal cases
• Paternity cases
• Medical diagnosis

Gel electrophoresis is also used for species classification and identifying human remains.

Question 15

What is the purpose of using restriction enzymes in DNA profiling?

Answer 15

To cut DNA into specific fragments

These fragments can then be analyzed for variations among individuals.

Question 16

In the context of DNA profiling, what indicates a match between a suspect and DNA found at a crime scene?

Answer 16

The bands in their DNA profile match the bands found at the scene

This matching process is essential for establishing guilt or innocence.

Question 17

How can you determine paternity using DNA profiling?

Answer 17

By comparing the child’s DNA bands to those of the parents

If a child’s DNA contains bands not present in the mother’s or father’s profiles, paternity can be excluded.

Question 18

What is one method for amplifying DNA?

Answer 18

Using PCR (Polymerase Chain Reaction)

PCR is essential for producing enough DNA for analysis in various applications.

Question 19

Fill in the blank: Gel electrophoresis separates DNA fragments based on their _______.

Answer 19

size

Question 20

What is the role of UV light in gel electrophoresis?

Answer 20

To visualize the separated DNA fragments

UV light helps in identifying and analyzing the banding patterns of DNA.

Question 21

What is the importance of using a filtering device in DNA extraction?

Answer 21

To remove debris from the DNA solution

Filtering ensures that only pure DNA is collected for further analysis.