What Do You Know About DNA Profiling? Trivia Questions Quiz

Explanation
The process of gel electrophoresis is used to separate DNA fragments based on their size and charge. This technique creates a unique pattern of DNA fragments, which is known as a DNA fingerprint. This pattern can be used to identify individuals or determine relationships between individuals. PCR (polymerase chain reaction) is a technique used to amplify specific DNA sequences, while STR (short tandem repeats) and VNTR (variable number tandem repeats) are types of DNA sequences that are commonly used in DNA fingerprinting.

Explanation
A gene is a segment of DNA that contains the instructions for building a specific protein or trait. It is the basic unit of heredity and is responsible for the transmission of traits from parents to offspring. Genes are located on chromosomes, which are structures within the cell nucleus. Alleles are different versions of a gene, and PCR (Polymerase Chain Reaction) is a laboratory technique used to amplify specific DNA sequences.

Explanation
A restriction enzyme is a molecule that cuts a DNA molecule at a specific base sequence. It recognizes a specific sequence of nucleotides and cuts the DNA at that site, creating fragments with sticky ends. This enzyme is commonly used in molecular biology techniques such as DNA cloning and genetic engineering. By cutting DNA at specific sites, restriction enzymes allow scientists to manipulate and study DNA sequences more effectively. PCR (polymerase chain reaction), STR (short tandem repeat), and VNTR (variable number tandem repeat) are not enzymes that cut DNA at specific base sequences, making them incorrect answers.

Explanation
STR stands for Short Tandem Repeat. It refers to the repetition of short DNA sequences, typically consisting of 2-5 base pairs in length. These repeats are found throughout the genome and can vary in the number of repetitions between individuals. STR analysis is commonly used in forensic science and paternity testing to compare DNA samples and determine genetic relationships. Therefore, the correct answer is STR.

Explanation
Gel electrophoresis is a widely used technique in molecular biology to separate DNA fragments based on their size. In this process, DNA is cut into smaller fragments using restriction enzymes and then placed on a gel. An electric current is applied to the gel, causing the DNA fragments to move through the gel matrix. Since smaller fragments move faster than larger ones, a pattern is created on the gel, allowing scientists to analyze and study the DNA. Therefore, the statement "The process where DNA is cut and placed on a gel where it moves based on size to create a pattern is known as Gel Electrophoresis" is true.

Explanation
In gel electrophoresis, DNA molecules are separated based on their size. This is because the gel matrix acts as a sieve, allowing smaller DNA fragments to move through the gel more quickly than larger fragments. As an electric current is applied, the negatively charged DNA molecules migrate towards the positive electrode. Smaller DNA fragments can move more easily through the pores of the gel, while larger fragments encounter more resistance and move slower. Therefore, the DNA in a gel electrophoresis does indeed separate based on its size.

Explanation
In gel electrophoresis, DNA fragments move through a gel matrix based on their size. Smaller fragments move faster and travel further, while larger fragments move slower and travel a shorter distance. Therefore, the correct answer is False, as larger size fragments do not travel the furthest.

Explanation
DNA can be extracted from various sources such as blood, semen, saliva, and hair follicles. These sources contain cells that contain DNA, which can be isolated and purified using various laboratory techniques. The DNA extraction process involves breaking open the cells, separating the DNA from other cellular components, and purifying it for further analysis. Therefore, it is true that DNA can be extracted from blood, semen, saliva, and hair follicles.

Explanation
Forensics examiners can determine if a suspect is linked to a crime scene by comparing the DNA found at the scene with the DNA of the suspects. DNA is unique to each individual, so if there is a match between the DNA at the crime scene and the DNA of a suspect, it provides strong evidence that the suspect was present at the scene. This is a commonly used technique in forensic investigations to establish a connection between a suspect and a crime.

Explanation
An allele is the correct answer because it refers to a gene that has more than one alternating form. In the case of blood types, there are multiple alleles that determine the different blood types such as A, B, and O. Each allele represents a different form of the gene that codes for the specific blood type.

Explanation
Chromosomes are long strands of DNA found in the nucleus of human cells. They contain genetic information and are responsible for carrying genes, which determine our traits and characteristics. Each human cell typically contains 46 chromosomes, arranged in 23 pairs. These chromosomes play a crucial role in cell division, reproduction, and the transmission of genetic material from one generation to the next.

Explanation
A molecule labeled with a radioactive isotope that attaches to a particular sequence of DNA is known as a probe. Probes are used in molecular biology to detect and identify specific DNA sequences. By attaching to the target DNA sequence, the probe allows scientists to visualize and study the DNA of interest. The radioactive isotope helps in the detection of the probe, allowing researchers to track and analyze the presence or absence of the specific DNA sequence in a sample.

Explanation
Electrophoresis is a method used to separate DNA molecules based on their size. It involves passing the DNA molecules through an agarose gel, which acts as a sieve, allowing smaller DNA fragments to move faster and further than larger ones. This technique is commonly used in DNA fingerprinting, where it helps to create a unique pattern or "fingerprint" of an individual's DNA. By comparing these patterns, scientists can determine the similarities and differences between DNA samples, which can be useful in various applications such as forensic investigations or paternity testing.

Explanation
PCR stands for Polymerase Chain Reaction, which is a method used to replicate small samples of DNA into millions of copies. It is a widely used technique in molecular biology and genetics research. PCR involves multiple cycles of heating and cooling to denature, anneal, and extend the DNA strands, allowing for exponential amplification of the target DNA sequence. This process is essential for various applications, such as DNA sequencing, genetic testing, and cloning.

Explanation
The given DNA code is repeated three times, indicating a variable number tandem repeat (VNTR). VNTRs are regions of DNA where a short sequence is repeated multiple times, and the number of repeats can vary between individuals. This variation in repeat number is what makes VNTRs useful for genetic analysis, such as in DNA profiling or forensic investigations.

Explanation
The correct answer is John because his DNA matches the DNA found at the crime scene.

Explanation
Suspect 2 left DNA at the crime scene because the answer indicates that S2 is the correct suspect.

Explanation
This statement is false because a DNA match between the crime scene and a suspect does not necessarily mean that the suspect committed the crime without a doubt. While DNA evidence can be strong evidence in a criminal investigation, it is not infallible. There is always a possibility of contamination, errors in analysis, or even the presence of an identical twin. Therefore, a DNA match alone cannot be considered conclusive proof of guilt.