UGC NTA NET/JRF Exam, Forensic Science, December-2023

The Sessions court is the highest judicial tribunal in a district and is located at the district headquarters. It has the authority to try all cases involving serious criminal offenses.

The Sessions court is empowered to impose any sentence, including the death penalty, though it requires confirmation from the High Court.

The Supreme Court, being the apex court, is not situated in district headquarters but in the nation's capital.

Executive Magistrates handle administrative and minor judicial functions at the district level but are not the highest tribunal. The High Court is the highest court at the state level, not the district level.

Aphasia is the condition characterized by the loss of ability to express meaning through speech or writing or to understand spoken or written language. It typically results from damage to parts of the brain responsible for language.

Cognition refers to mental processes such as thinking, knowing, and remembering. Delirium is an acute, often fluctuating disturbance of consciousness and cognition. Delusion is a false belief held despite evidence to the contrary.

Unlike aphasia, these conditions do not specifically impair language expression or comprehension.

It is not preferable to scrape or cut the stain area and then pack when sending exhibits to the Forensic Science Laboratory (FSL) if the stain is on a transportable object. Scraping or cutting can lead to the loss of crucial evidence and contamination.

Sending the whole object, protecting the stained area, and enclosing it in a package are all preferred methods to maintain the integrity and prevent contamination of the evidence.

This ensures that the FSL can conduct a comprehensive analysis without the risk of losing or altering the evidence.

Sir Edward Henry is known for the fingerprint classification system adopted in British India and the United Kingdom and wrote the book "Classification and Uses of Fingerprints.

" His system, the Henry Classification System, is a method of cataloging fingerprints that is still in use today. Dr. Henry Faulds and Sir William Hershel contributed to early fingerprinting methods but did not develop the classification system.

Juan Vucetich developed a different fingerprint classification system used in South America.

Satellite DNA consists of non-protein coding sequences. These repetitive DNA sequences are found in the genome but do not encode proteins. Instead, they play a role in structural functions of the chromosome, such as centromere formation.

Protein coding DNA sequences, known as genes, direct the synthesis of proteins. mRNA coding sequences are involved in the transcription of DNA into messenger RNA, which is then translated into proteins. Satellite protein coding is incorrect as satellite DNA does not code for proteins.

In DNA fingerprinting analysis, probes used are made up of single-stranded labeled DNA. These probes are designed to hybridize to specific sequences in the DNA sample, allowing for the detection of particular DNA fragments.

The labeling of the probes (often with a radioactive or fluorescent tag) enables visualization after hybridization. Satellite DNA, although used as a target in some probes, is not itself a probe.

RNA is not typically used as a probe in DNA fingerprinting due to stability issues. Double-stranded unlabelled DNA would not provide the necessary specificity or detectability required for the analysis.

Variable Number of Tandem Repeats (VNTRs) in DNA fingerprinting analysis belong to mini satellites. VNTRs are repeating sequences of 10-60 base pairs found in the genome.

These sequences vary in number among individuals, making them useful for genetic profiling. Nano satellites and macro satellites do not refer to VNTRs. Kilo satellites are not a recognized category in this context.

The variability in the number of repeats in mini satellites forms the basis for differentiating individuals' DNA profiles in forensic and genetic studies.

Luminol in the presence of the heme part of hemoglobin undergoes oxidation by adding hydrogen peroxide in an alkaline solution. This reaction produces a blue glow (chemiluminescence), which is used to detect blood traces at crime scenes.

Hydrogen sulphide, acetic acid, and sodium chloride do not cause the luminol reaction to occur in the same way. Hydrogen peroxide is crucial for the oxidation process, allowing the chemiluminescence that reveals blood traces even in small quantities.

The drug with the street name "Skunk" is marijuana. Skunk is a potent strain of cannabis known for its strong smell and high levels of tetrahydrocannabinol (THC). Cocaine, khat, and zolpidem have different street names and effects.

Cocaine is a powerful stimulant, khat is a plant with stimulant effects, and zolpidem is a prescription medication used to treat insomnia. The term"Skunk" specifically refers to the cannabis strain and its distinctive characteristics.

Phenolphthalein used in trap cases is replaced by a mixture of phenolphthalein and hydroquinone (100:2) so that the resulting pink color does not fade for years. Hydroquinone stabilizes the colour, ensuring longevity.

Benzoic acid, phenol, and sodium carbonate do not provide the same stabilizing effect. This mixture is crucial in forensic applications to maintain the visibility of the evidence over extended periods, aiding in long-term investigations and legal proceedings.