Biology · Law Legal Studies

Forensic Science Techniques

725 Questions

Forensic science techniques involve the application of scientific methods like DNA fingerprinting, biometrics, and trace evidence analysis to solve crimes. These topics appear in specialized law enforcement and general science exams. Practice these questions to understand forensic fundamentals.

DNA fingerprinting methodsTrace evidence transferBiometrics and identificationForensic pathology

Forensic Science Techniques Questions

Multiple choice zoology mutation dna fingerprinting human genome project and dna fingerprinting instruments in biotechnology

In DNA finger printing, analysis is made of

  1. Satellite DNA

  2. Moderately repetitive sequences

  3. Microsatellites

  4. Variable number of tandem repeats
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

DNA fingerprinting relies on detecting variations in specific repetitive DNA regions. Variable Number of Tandem Repeats (VNTRs) are highly polymorphic sequences used as markers for individual identification.

Multiple choice zoology mutation dna fingerprinting human genome project and dna fingerprinting instruments in biotechnology

Process used for amplication or multiplication of DNA for finger printing is

  1. Polymerase chain reaction

  2. Nesslerisation

  3. Southern blotting

  4. Northern blotting
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Polymerase Chain Reaction (PCR) is the standard laboratory technique used to amplify small segments of DNA, making them sufficient for analysis in fingerprinting.

Multiple choice zoology mutation dna fingerprinting human genome project and dna fingerprinting instruments in biotechnology

The probes for DNA finger printing are

  1. Unknown single stranded labelled DNA

  2. Unknown double stranded labelled DNA

  3. Known single stranded labelled DNA

  4. Known double stranded unlabelled DNA
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Probes used in DNA fingerprinting are known, single-stranded DNA sequences that are radioactively or fluorescently labeled to bind specifically to complementary target sequences on the membrane.

Multiple choice zoology mutation dna fingerprinting human genome project and dna fingerprinting instruments in biotechnology

Assertion : Thermographic imaging is a unique technique.

Reason : Thermographic imaging has some relation with DNA finger printing. 

  1. If both assertion and reason are true and the reason is the correct explanation of the assertion.

  2. If both assertion and reason are true but reason is not the correct explanation of the assertion.

  3. If assertion is true but reason is false.

  4. If the assertion and reason both are false.

  5. If assertion is false but reason is true.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Thermographic imaging is a technique for detecting heat radiation, while DNA fingerprinting is a biological analysis method. They are distinct fields with no direct functional relationship.

Multiple choice zoology mutation dna fingerprinting human genome project and dna fingerprinting instruments in biotechnology

For DNA fingerprinting to associate a blood sample with the criminal, what is minimally required

  1. One sample of DNA, PCR amplification, restriction enzymes, and gel electrophoresis

  2. One sample of DNA, restriction enzymes, a DNA synthesizer, and gel electrophoresis

  3. Two samples of DNA, PCR amplification, restriction enzymes, and gel electrophoresis

  4. Two samples of DNA, PCR amplification, restriction enzymes, and a DNA synthesizer
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Two samples of DNA are required, one from the site of crime while another from the suspected criminal. These both samples of DNA are matched by DNA fingerprinting which involves identifying patterns of DNA known as a variable number of tandem repeats. PCR amplification is used to amplify DNA segments and restriction enzymes for cutting of DNA segments. Gel electrophoresis is used to separate these cut DNA segments based on their size. 

So, the correct option is 'Two samples of DNA, PCR amplification, restriction enzymes, and gel electrophoresis'.

Multiple choice zoology mutation dna fingerprinting human genome project and dna fingerprinting instruments in biotechnology

Arrange the various steps of DNA fingerprinting technique in the correct order
(i) Separation of DNA fragments by electrophoresis
(ii) Digestion of DNA by restriction endonucleases
(iii) Hybridization using labeled VNTR probe
(iv) Isolation of DNA
(v) Detection of hybridized DNA fragments by autoradiography
(vi) Transferring the separated DNA fragments to nitrocellulose membrane

  1. (ii) $\rightarrow$ (i) $\rightarrow$ (iv) $\rightarrow$ (vi) $\rightarrow$ (iii) $\rightarrow$ (v)
  2. (iv) $\rightarrow$ (i) $\rightarrow$ (ii) $\rightarrow$ (iii) $\rightarrow$ (vi) $\rightarrow$ (v)
  3. (iv) $\rightarrow$ (ii) $\rightarrow$ (i) $\rightarrow$ (vi) $\rightarrow$ (iii) $\rightarrow$ (v)
  4. (iii) $\rightarrow$ (v) $\rightarrow$ (iv) $\rightarrow$ (ii) $\rightarrow$ (i) $\rightarrow$ (vi)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The technique of DNA Fingerprinting was initially developed by Alec Jeffreys. It included : -
  1.  isolation of DNA,
  2.  digestion of DNA by restriction endonucleases,
  3.  separation of DNA fragments by electrophoresis,
  4. transferring (blotting) of separated DNA fragments to synthetic membranes, such as nitrocellulose or nylon, 
  5. hybridisation using labelled VNTR probe, and
  6. detection of hybridised DNA fragments by autoradiography.
So, the correct option is '(iii) → (v) → (iv) → (ii) → (i) → (vi)'.
Multiple choice botany breeding and biotechnology branches of biotechnology gene cloning biotechnology and genetic engineering

The process of 'in vitro' manipulation of DNA is called as

  1. Tissue culture

  2. Genetic engineering

  3. Cloning

  4. DNA fingerprinting
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Recombinant DNA technology is also referred to as gene cloning or in- vitro genetic manipulation. Genetic manipulation or engineering alters the genetic make-up of an organism using techniques that remove heritable material or that introduce DNA prepared outside the organism either directly into the host or into a cell that is then fused or hybridized with the host. This involves using recombinant nucleic acid (DNA or RNA) techniques to form new combinations of heritable genetic material followed by the incorporation of that material either indirectly through a vector system or directly through micro-injection, macro-injection and micro-encapsulation techniques.
Therefore, the correct answer is option B.
Multiple choice zoology genetics of the future hgp and dna fingerprinting dna fingerprinting human genome project and dna fingerprinting

A biotechnological process that has found a significant application in the field of forensic science is

  1. Recombination DNA technology

  2. Tissue culture

  3. DNA fingerprint technology

  4. Genetic engineering
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • DNA fingerprinting also called DNA typing, DNA profiling, genetic fingerprinting, genotyping, or identity testing, in genetics is a method of isolating and identifying variable elements within the base-pair sequence of DNA (deoxyribonucleic acid). 
  • DNA fingerprinting is currently used both for identifying paternity or maternity and for identifying criminals or victims.
Multiple choice zoology genetics of the future hgp and dna fingerprinting dna fingerprinting human genome project and dna fingerprinting

Matching DNA sequence of criminal with suspect is known as

  1. DNA finger printing

  2. DNA amplification

  3. Gene mapping

  4. DNA resolution
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DNA amplification is the synthesis of multiple copies of small DNA sample which is done by PCR technique. It amplifies the gene of interest in three steps namely denaturation of target DNA (thermal cycle to separate the DNA strands), annealing of primers to the ssDNA and polymerization (extension of primer into complete DNA strand complementary to the template strand). 

Gene mapping is identifying the location of different genes on a chromosome. It is done using recombination frequency (which does not correspond to physical distance) or using RFLPs that generate physical maps. 
The DNA polymorphism in simple-sequence DNA and VNTRs has revealed during DNA finger printing in the identification of suspect since it is very remote possibility to have two individuals same repeats of satellite DNA throughout the genome except they share a biological relationship. This is because a child gets half DNA from father and half from the mother. Restriction enzymes of genome produce the restriction fragments length polymorphisms, or RFLPs depending on the location of restriction sites which are then sorted by gel electrophoresis followed by southern blotting. The blots of the suspect and of the sample from the crime scene are compared for sequence homology using radioactive probes; option A is the correct answer.

Multiple choice zoology genetics of the future hgp and dna fingerprinting dna fingerprinting human genome project and dna fingerprinting

Which of the following can result in inaccurate test results in DNA fingerprinting?

  1. Sample size

  2. Tissue decay

  3. Blood transfussion

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The possibility of having inaccurate test results increases if a very small sample of DNA is available for testing. The chance that the DNA will be mixed up with some other DNA is also higher with a smaller sample. If a person had a blood transfusion within the past 3 months which make the availability of DNA sample of different types. The decay of the tissue sample can also lead to inaccurate results. Therefore, the correct answer is option D.