2013 September NTA UGC-NET / JRF Previous Year Solved Question Paper, Part -1

Answer: C. 4 °C

Explanation: For preserving a dead body for autopsy, the preferred temperature for the cold chamber is typically around 4 °C (or slightly above freezing). This temperature helps slow down the decomposition process and maintains the body’s condition for a more accurate examination. Lower temperatures below freezing or higher temperatures above 4 °C may affect the body’s integrity and hinder the autopsy process.

Answer: C. Cooling of the body

Explanation: The immediate changes after death include the cessation of brain function, cessation of heart function, and stoppage of respiration. However, the cooling of the body is not an immediate change; it is a gradual process known as algor mortis, which occurs over a period of time after death. The body temperature initially remains close to the normal body temperature and then gradually decreases as heat dissipates from the body.

Answer: A. iii i iv ii

Explanation: The matching of the given compounds with their respective chemical structures is crucial in forensic toxicology and environmental analysis. Parathion is an organophosphate insecticide with the structure O,O-diethyl-O-p-nitrophenylthio phosphate. Dimethoate is another organophosphate with the structure O,O-dimethyl-S-dithio phosphate. Phosphamidon is an insecticide with the structure O,O-Dimethyl dithiophosphate of diethyl mercapto-succinate, and Malathion is an organophosphate insecticide with the structure O,(2-chloro-2-diethyl carbamoyl)-1-methyl-vinyl-O,O-di-methmyl-phosphate. Proper identification of these compounds is essential for investigating cases of poisoning or environmental contamination.

Answer: B. ii iii iv i

Explanation: In forensic psychology and psychiatric evaluations, understanding the different types of mental disorders and their manifestations is crucial. A delusion is a false belief that is firmly held despite evidence to the contrary, while a hallucination is a sensory experience that occurs without an external stimulus. An illusion, on the other hand, is a misinterpretation of an actual external stimulus. Kleptomania is a psychological disorder characterized by an irresistible urge to steal items, often of trivial value, without any apparent need or personal gain. Accurately identifying and distinguishing these conditions is important in criminal investigations and legal proceedings.

Answer: C. Lugol’s iodine test

Explanation: In cases of sexual assault, the identification of vaginal epithelial cells is crucial for forensic evidence. The Lugol’s iodine test is a simple and effective technique used to detect and identify the presence of vaginal epithelial cells. This test involves staining the sample with Lugol’s iodine solution, which reacts with the glycogen present in the vaginal epithelial cells, causing them to turn a characteristic brown or reddish-brown color. This color change allows for the identification and confirmation of vaginal epithelial cells, which can be used as evidence in sexual assault cases.

Answer: A. Age of Fetus

Explanation: The Rule of Hasse, also known as Hasse’s rule or the neonatal line, is a method used in forensic anthropology and pediatrics to estimate the age of a fetus or a newborn infant based on the length of the long bones, particularly the femur. This rule takes into account the linear relationship between the length of the fetal femur and the gestational age or the age of the newborn. It is a valuable tool for determining the age of a fetus in cases involving infanticide, abortion, or other related investigations.

Answer: D. Tetanus

Explanation: Rigor mortis, or the temporary stiffening of the body after death, is caused by biochemical changes in the muscles. Conditions like cold stiffening, gas stiffening, and pugilistic attitude (a defensive posture with clenched fists) can resemble or mimic rigor mortis. However, tetanus, a severe neurological disorder caused by the toxin produced by Clostridium tetani bacteria, does not resemble rigor mortis. Tetanus causes muscular rigidity and spasms in a living person due to the toxin’s effects on the nervous system, which is different from the post-mortem stiffening observed in rigor mortis.

Answer: C. eight

Explanation: In a child aged 7 years, the total number of temporary molars (also known as deciduous molars or primary molars) is typically eight. These molars are part of the primary dentition, or the first set of teeth that erupt in a child’s mouth. The temporary molars consist of four molars in the upper jaw (two on each side) and four molars in the lower jaw (two on each side), making a total of eight temporary molars. These temporary molars will eventually be replaced by permanent molars as the child grows older.

Answer: A. Drowning

Explanation: The presence of fine, white, lathery froth that is copious and tenacious (sticky) around the mouth and nostrils is a characteristic sign of death due to drowning. When a person drowns, the inhalation of water into the lungs causes the production of a frothy mixture of air, water, and mucus, which is expelled from the respiratory system and accumulates around the mouth and nostrils. This frothy discharge is a valuable indicator for forensic pathologists in determining drowning as the cause of death, especially when other signs and evidence are inconclusive.

Answer: B. Pelvis

Explanation: In forensic anthropology, the pelvis is considered the best bone for determining the sex of an individual from skeletal remains. The pelvis exhibits significant morphological differences between males and females due to its role in childbirth and the associated adaptations. The shape, size, and features of the pelvic bones, such as the subpubic angle, ventral arc, and the greater sciatic notch, vary between the sexes. These differences make the pelvis a highly reliable indicator for sex determination, even when other bones may be fragmented or incomplete.

Answer: A. Intermingling of sexual traits in a person

Explanation: Intersex is a term used to describe individuals who are born with reproductive or sexual anatomy that does not fit the typical definitions of male or female. Intersex individuals may possess a combination of chromosomal, hormonal, and anatomical features that are typically associated with both sexes. This intermingling of sexual traits can result in ambiguous genitalia or variations in sexual characteristics. Intersex conditions are relatively rare and can have various causes, including genetic, hormonal, or developmental factors. Proper understanding and recognition of intersex individuals are important in forensic investigations and legal proceedings.

Answer: A. 9.14 mm

Explanation: LG shot, or large game shot, is a type of shotgun ammunition designed for hunting larger animals. The diameter of LG shot pellets is typically around 9.14 mm (0.36 inches). This larger size provides greater penetration and stopping power compared to smaller shot sizes, making it suitable for hunting big game at longer distances.

Answer: B. Multiple barrel

Explanation: Derringers are small, compact pistols that typically have multiple barrels, usually two. These barrels can be arranged either side-by-side or over-under. The multiple barrels allow for quick successive shots without the need for reloading. Derringers are known for their concealability and were popular in the 19th century as a close-range self-defense weapon.

Answer: B. K.E. = 1/2 MV^2

Explanation: The kinetic energy (K.E.) of a moving projectile is determined by the equation K.E. = 1/2 MV^2, where M is the mass of the projectile and V is its velocity. This equation shows that the kinetic energy is directly proportional to the square of the velocity, meaning that doubling the velocity will quadruple the kinetic energy. The 1/2 in the equation comes from the integration of the force over the distance traveled.

Answer: D. (a) and (d) are correct

Explanation: In the context of firearm mechanisms, trombone action refers to both pump action and slide action. These terms describe a type of repeating firearm action that involves manually moving a sliding handguard or fore-end to eject a spent cartridge and load a new one into the chamber. This motion resembles the slide of a trombone musical instrument, hence the name. Pump-action and slide-action are often used interchangeably, and both are commonly seen in shotguns.

Answer: B. Fouling

Explanation: Fouling, which refers to the accumulation of residue from burnt gunpowder and other materials inside the barrel of a firearm, can be used to estimate the probable time of the last fire. As time passes after a firearm is discharged, the residue begins to oxidize and change in composition. By analyzing the degree of oxidation and the chemical composition of the fouling, forensic experts can estimate the time elapsed since the last shot was fired. This information can be crucial in reconstructing timelines and corroborating witness statements in criminal investigations.

Answer: C. Both (A) and (R) are correct.

Explanation: In the Absorption-Inhibition method, a specific antigen is allowed to bind with its corresponding antibody by placing them in contact with each other. This process is called absorption. As a result of this absorption, the serum containing the antibody becomes less potent or less effective in its activity. The degree of inhibition of the serum’s activity is then measured to quantify the amount of antigen present. This method is widely used in immunological assays for the detection and quantification of antigens or antibodies in a sample.

Answer: D. Desmethyldiazepam

Explanation: Benzodiazepines are a class of psychoactive drugs commonly used for their sedative, anxiolytic, and hypnotic properties. When metabolized in the body, benzodiazepines undergo various biotransformations, primarily in the liver. The major metabolite of many benzodiazepines, including diazepam (Valium), is desmethyldiazepam, also known as nordiazepam. Desmethyldiazepam is an active metabolite that contributes to the pharmacological effects of benzodiazepines. Its presence can be detected in urine and blood tests, making it an important marker in forensic toxicology for determining benzodiazepine use or abuse.

Answer: C. Chromatography

Explanation: BHC (Benzene Hexachloride) is an organochlorine insecticide that consists of several isomers. The presence of BHC in a sample can be established by separating its constituents using chromatography techniques. Chromatography is a powerful analytical method that allows for the separation, identification, and quantification of components in a mixture based on their differential affinities to a stationary phase and a mobile phase. Gas chromatography (GC) and high-performance liquid chromatography (HPLC) are commonly used for the analysis of pesticide residues like BHC in environmental and biological samples.

Answer: C. Calatropis

Explanation: The ester test is a chemical test used for the identification of cardiac glycosides, which are organic compounds containing one or more sugar molecules attached to a steroid or triterpene nucleus. Cardiac glycosides are found in several plants, including Calotropis, a genus of flowering plants commonly known as milkweeds. The ester test involves the hydrolysis of the glycoside’s ester linkage using sodium hydroxide, followed by the addition of ferric chloride. The development of a reddish-brown color indicates the presence of an ester group, confirming the presence of a cardiac glycoside. This test is particularly useful in the detection of Calotropis poisoning in forensic toxicology.

Answer: B. Periodic acid-schiff reagent

Explanation: The periodic acid-Schiff (PAS) reagent is used to identify vaginal secretions by detecting glycogenated epithelial cells. Glycogen is a polysaccharide that is present in high amounts in vaginal epithelial cells. The PAS staining method involves two steps: first, periodic acid oxidizes the glycol groups in glycogen, creating aldehydes; second, the Schiff reagent reacts with these aldehydes to produce a distinctive magenta color. The presence of glycogenated epithelial cells, as evidenced by the PAS stain, is a strong indicator of vaginal secretions. This test is particularly useful in sexual assault cases to establish the presence of vaginal fluid on suspects or victims.

Answer: D. Hematospermia

Explanation: Hematospermia, also known as hemospermia, is the presence of blood in semen, which can cause the semen to appear pink or reddish in color. This condition can be caused by various factors, including infections, trauma, tumors, or bleeding disorders. While hematospermia is often benign and self-resolving, it can sometimes indicate a more serious underlying condition. In forensic contexts, the presence of hematospermia in semen stains can provide valuable information about the time since ejaculation and the health status of the individual. Other terms related to semen abnormalities include azoospermia (absence of sperm), oligospermia (low sperm count), and histospermia (presence of lymphocytes in semen).

Answer: A. Watson and Crick

Explanation: The double helix structure of DNA was first reported by James Watson and Francis Crick in 1953. Their discovery was based on X-ray diffraction images of DNA obtained by Rosalind Franklin and Maurice Wilkins. Watson and Crick’s model of the DNA double helix consisted of two polynucleotide chains coiled around each other, with the phosphate backbone on the outside and the nitrogenous bases on the inside. The bases form complementary pairs (A with T, and G with C) through hydrogen bonds, stabilizing the double helix. This groundbreaking discovery laid the foundation for the field of molecular biology and has had profound implications in various fields, including forensic science, where DNA profiling is used for individual identification and paternity testing.

Answer: A. Secretors

Explanation: Secretors are individuals who secrete ABO blood group antigens (A, B, and H substances) in their body fluids, such as saliva, sweat, tears, and seminal fluid. The ability to secrete these antigens is controlled by the Se gene, which is dominant. Secretors possess at least one Se gene (SeSe or Sese), while non-secretors are homozygous for the recessive se gene (sese). In forensic serology, the determination of secretor status can be useful in narrowing down the pool of potential suspects or linking a suspect to a crime scene. Approximately 80% of the population are secretors, while 20% are non-secretors. Lewis antigens, which are related to the secretor status, are not directly involved in the secretion of ABO blood group substances.

Answer: A. 2-7 bp

Explanation: Short Tandem Repeats (STRs) are repetitive DNA sequences used extensively in forensic DNA profiling. STRs consist of short sequences of DNA base pairs (bp), typically 2-7 bp in length, that are repeated multiple times in tandem. For example, the STR locus D7S820 has the repeat unit GATA, so alleles at this locus might have 8, 10, or 12 GATA repeats. The small size of STR repeats allows for efficient PCR amplification, even from degraded DNA samples. STRs are highly polymorphic, meaning that there are many alleles (variations) at each locus, making them excellent markers for individual identification. In contrast, longer repeat units, such as 242 bp or 1100 bp, are characteristic of other types of repetitive DNA elements, like minisatellites or microsatellites, which are less commonly used in forensic applications.

Answer: D. its ability to polarize light

Explanation: Scanning Electron Microscopy (SEM) is a powerful imaging technique that provides high-resolution, detailed images of sample surfaces. The major advantages of SEM include its great depth of field, allowing for focused images of uneven surfaces; its high resolution, enabling the visualization of nanoscale features; and its high magnification, providing up to hundreds of thousands of times magnification. However, SEM does not have the ability to polarize light, as it uses electrons instead of light to form images. Polarized light microscopy is a different technique that utilizes polarized light to enhance contrast and reveal structural information in optically anisotropic samples.

Answer: B. enantiomers

Explanation: Infrared (IR) spectroscopy is a widely used analytical technique that provides information about the functional groups and molecular structure of a sample. However, IR spectra fail to distinguish between enantiomers, which are mirror-image molecules that have the same chemical formula and connectivity but differ in their spatial arrangement. Enantiomers have identical IR spectra because they absorb IR light at the same wavelengths. To differentiate between enantiomers, techniques like polarimetry, chiral chromatography, or vibrational circular dichroism (VCD) spectroscopy must be employed. IR spectroscopy can, however, distinguish between tautomers (structural isomers that readily interconvert), conformers (different spatial arrangements of a molecule), and diastereomers (stereoisomers that are not mirror images).

Answer: B. N.A. = n sin θ

Explanation: The numerical aperture (N.A.) of an objective lens is a dimensionless number that characterizes the range of angles over which the lens can accept or emit light. It is defined as N.A. = n sin θ, where n is the refractive index of the medium between the lens and the sample (typically air, with n ≈ 1), and θ is the half-angle of the maximum cone of light that can enter or exit the lens. A higher N.A. indicates a wider cone of light and a higher resolving power. The N.A. is a crucial parameter in microscopy, as it determines the resolution and light-gathering ability of the objective lens. The other equations given in the options are not the correct definition of numerical aperture.

Answer: C. (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i)

Explanation: The electromagnetic spectrum covers a wide range of wavelengths, from radio waves to gamma rays. The correct matches between the spectral regions and their wavelength ranges are: Ultraviolet light – 2000-4000 Å (200-400 nm); Visible light – 4000-8000 Å (400-800 nm); X-ray – 0.1-100 Å (0.01-10 nm); Near IR region – 2.5-25 μ (2500-25000 nm). Ultraviolet light has shorter wavelengths than visible light, while near-infrared light has longer wavelengths. X-rays have much shorter wavelengths than both UV and visible light. Understanding the wavelength ranges of different spectral regions is essential for selecting appropriate analytical techniques and interpreting spectroscopic data in forensic science.

Answer: B. Shimla

Explanation: The first Government Examiner of Questioned Documents (G.E.Q.D.) in India was established in Shimla in 1904. The G.E.Q.D. is responsible for the forensic examination and comparison of questioned handwriting, signatures, and other documents to determine their authenticity, authorship, or any alterations. The establishment of the G.E.Q.D. in Shimla marked the beginning of formalized questioned document examination in India. Since then, several other G.E.Q.D. offices have been set up across the country to cater to the increasing demand for document analysis in civil and criminal cases. The G.E.Q.D. plays a crucial role in the administration of justice by providing expert opinions on the genuineness of documents and helping to detect forgeries and fraud.

Answer: D. Children below 18 years

Explanation: Juvenile courts are specialized courts that handle cases involving children and adolescents who are accused of committing criminal offenses or who are in need of care and protection. In most jurisdictions, juvenile courts have jurisdiction over individuals below the age of 18 years, as they are considered minors in the eyes of the law. The primary goal of juvenile courts is to focus on rehabilitation and reformation rather than punishment. These courts operate under a separate set of procedural rules and guidelines that are designed to be more child-friendly and less adversarial than adult criminal courts. Juvenile courts do not deal with cases involving mentally ill persons, foreign citizens, or criminal lawyers, as these fall under the purview of other specialized courts or legal provisions.

Answer: D. High Court

Explanation: In the Indian judicial system, the High Court is not a court of trial. It is primarily an appellate court that hears appeals from lower courts and tribunals within its territorial jurisdiction. The High Court also has the power to issue writs for the enforcement of fundamental rights and to exercise supervisory jurisdiction over subordinate courts. The other courts mentioned – Chief Judicial Magistrate, First Class Judicial Magistrate, and Additional District and Session Judge – are all trial courts that conduct trials in criminal and civil cases based on their respective jurisdictions. These courts hear evidence, examine witnesses, and pass judgments in the first instance. If a party is aggrieved by the decision of a trial court, they can appeal to the High Court for redressal.

Answer: A. (a)-(iv), (b)-(i), (c)-(ii), (d)-(iii)

Explanation: The correct matches between the forensic science pioneers and their areas of expertise are: DNA – Alec Jeffreys, who developed the technique of DNA fingerprinting; Documents – Albert S. Osborn, a pioneer in questioned document examination; Ballistics – Major Gerald Burrard and Colonel Calvin Goddard, key figures in the development of forensic ballistics (Hatcher being a misspelling or confusion with Julian Hatcher, a noted firearms expert); Blood – Karl Landsteiner, who discovered the ABO blood group system. These individuals made significant contributions to their respective fields, laying the foundation for modern forensic science practices. Their work has had a profound impact on the investigation of crimes and the administration of justice worldwide.

Answer: D. After drying under shade

Explanation: When collecting blood-stained soil from a crime scene, it is essential to handle the evidence properly to prevent contamination and preserve its integrity for forensic analysis. The recommended procedure is to allow the soil to dry under shade before packaging and sending it for examination. Drying the soil under shade ensures that the blood stains are not subjected to direct sunlight or heat, which can cause degradation of the blood proteins and DNA. Drying also prevents the growth of mold and bacteria that can further contaminate the sample. Sending the soil without drying or after drying in an oven or under a fan is not advisable, as these methods can alter the composition of the blood and soil, leading to inaccurate results. Proper drying and packaging of blood-stained soil are crucial for successful forensic analysis and the generation of reliable evidence.

Answer: C. P30

Explanation: Prostate-specific antigen (PSA) is a protein produced by the prostate gland in males. It is also known as P30 or semenogelins. PSA is a serine protease that liquefies the seminal coagulum after ejaculation, allowing spermatozoa to move freely. In forensic serology, the detection of PSA is used as a confirmatory test for the presence of semen in sexual assault cases. Elevated levels of PSA in vaginal fluid or on vaginal swabs can indicate recent sexual activity. PSA is not related to proteinase K (a broad-spectrum serine protease), amylase (an enzyme that breaks down starch), or ptylase (a misnomer, likely referring to a different enzyme). The specificity of PSA to semen makes it a valuable marker in forensic investigations involving sexual assault or rape.

Answer: B. Prostate gland

Explanation: Seminal acid phosphatase (SAP) is an enzyme produced primarily by the prostate gland in males. It is a major constituent of seminal fluid, accounting for about 1% of the total seminal volume. SAP is responsible for the hydrolysis of phosphoric acid esters, which helps in the liquefaction of semen after ejaculation. In forensic serology, the detection of elevated levels of SAP is used as a presumptive test for the presence of semen in sexual assault cases. SAP is not produced in significant quantities by other glands such as the adrenal, thyroid, or pituitary glands. The specificity of SAP to the prostate gland and its presence in high concentrations in semen make it a reliable marker for identifying seminal stains in forensic investigations.

Answer: C. Cortical fussi

Explanation: Cortical fusi, also known as cortical fusiform bodies or cortical vacuoles, are microscopic air-filled spaces found within the cortex of human and animal hair. These elongated, spindle-shaped structures are formed during the keratinization process of hair growth. Cortical fusi are more prevalent in coarser, thicker hair and are less common in fine, thin hair. The presence and distribution of cortical fusi can vary among individuals and are influenced by factors such as age, hair type, and genetic background. In forensic hair analysis, the examination of cortical fusi can provide useful information about the species of origin and the potential source of a questioned hair sample. However, the presence of cortical fusi alone is not sufficient for individual identification, and other microscopic features and chemical analyses are required for a more conclusive comparison.

Answer: D. Creatinine picrate

Explanation: Creatinine is a waste product generated from the metabolism of creatine in muscle tissue. It is excreted primarily in urine and is used as a marker of kidney function. The Jaffe reaction, developed by Max Jaffe in 1886, is a commonly used method for the colorimetric determination of creatinine in urine and serum. In this reaction, creatinine reacts with picric acid under alkaline conditions to form a reddish-orange complex called creatinine picrate. The intensity of the color produced is proportional to the concentration of creatinine in the sample and can be measured using a spectrophotometer. The Jaffe reaction is not specific to creatinine and can be affected by the presence of other interfering substances such as glucose, proteins, and ketones. More specific enzymatic methods have been developed for creatinine measurement in clinical settings.

Answer: A. tyrosinase activity

Explanation: The graying of hair is primarily caused by a decrease in the activity of the enzyme tyrosinase. Tyrosinase is a copper-containing enzyme that catalyzes the production of melanin, the pigment responsible for hair color. Melanin is synthesized in specialized cells called melanocytes, which are located in the hair follicles. As we age, the activity of tyrosinase decreases, leading to a reduction in melanin production and the appearance of gray or white hair. Other factors that can influence the graying of hair include genetics, stress, nutritional deficiencies, and certain medical conditions. Proteinase, pectinase, and glucomylase are enzymes involved in the breakdown of proteins, pectin, and starch, respectively, and do not play a significant role in the graying process of hair.

Answer: A. Pattern area

Explanation: In fingerprint analysis, type lines are defined as the two innermost ridges that start parallel, diverge, and surround or tend to surround the pattern area. The pattern area is the central portion of a fingerprint that contains the core and the delta. The core is the innermost point or center of the fingerprint pattern, while the delta is the point where three ridges come together to form a triangle. Type lines are used to classify fingerprint patterns into different categories, such as loops, whorls, and arches. They help in determining the orientation and shape of the pattern area and are essential for accurate fingerprint comparison and identification. Type lines are not related to the inner terminus (the point where the ridge ends), outer terminus (the point where the ridge starts), or delta (which is not surrounded by type lines).

Answer: B. 1/1

Explanation: In the Henry Classification System, which is a method of classifying fingerprints based on their pattern types, all ten fingers having a loop pattern will have a classification of 1/1. The Henry system assigns numerical values to different fingerprint patterns, with loops being assigned a value of 1. When all ten fingers have loops, the primary and secondary classifications are both 1, resulting in a 1/1 classification. Other possible classifications include 0/0 for all arches, 32/32 for all whorls, and 64/64 for a mix of different patterns across the fingers. The Henry Classification System provides a way to categorize and narrow down fingerprint records for faster comparison and identification in criminal investigations and other applications involving fingerprint analysis.

Answer: A. Small Particle Reagent (SPR)

Explanation: Small Particle Reagent (SPR) is a technique used to develop latent fingerprints on wet or damp non-porous surfaces, such as plastic, glass, or metal. SPR consists of a suspension of fine particles, typically molybdenum disulfide or titanium dioxide, in a detergent solution. When the reagent is applied to a wet surface containing latent fingerprints, the particles adhere to the fatty components of the fingerprint residue, making the print visible. SPR is particularly useful in cases where the surface has been exposed to moisture or humidity, as traditional fingerprint powders may not work effectively under these conditions. Ninhydrin, crystal violet, and amido black are chemical reagents used to develop latent prints on porous surfaces like paper or cardboard, and are not suitable for wet non-porous surfaces.

Answer: A. dots of i and j

Explanation: In handwriting analysis, diacritic marks are the small, additional strokes or symbols that are added to letters to modify their sound or meaning. The dots above the lowercase letters “i” and “j” are classic examples of diacritic marks in the English alphabet. These dots, known as tittle, are used to differentiate these letters from other similar-looking letters, such as uppercase “I” or lowercase “l”. The presence, placement, and shape of the dots can vary between individuals and can provide valuable information about the writer’s handwriting habits, speed, and attention to detail. Other examples of diacritic marks include the accent marks used in various languages, such as the acute accent (é), grave accent (è), and circumflex (ê). The loops of letters g, j, p, and y are integral parts of those letters and are not considered diacritic marks.

Answer: A. Super glue

Explanation: Super glue fuming, also known as cyanoacrylate fuming, is a highly effective technique for developing latent fingerprints on non-porous surfaces such as plastic, glass, and metal. The process involves exposing the surface containing the latent prints to the fumes of super glue (ethyl cyanoacrylate) in a controlled environment, such as a fuming chamber. The cyanoacrylate molecules react with the moisture and fatty components in the fingerprint residue, forming a white, hard polymer that makes the prints visible. Super glue fuming is sensitive, reliable, and can develop prints on surfaces that have been exposed to adverse conditions. Ninhydrin and diazafluorenone (DFO) are used for developing prints on porous surfaces, while crystal violet is a dye stain used for enhancing blood marks or prints on adhesive surfaces. These techniques are not typically used for non-porous surfaces.

Answer: D. Becke line

Explanation: The Becke line is a bright halo or line that appears near the border of a transparent particle, such as a glass fragment, when it is immersed in a liquid with a different refractive index and observed under a microscope. This optical phenomenon is named after the Austrian mineralogist Friedrich Johann Karl Becke, who first described it in 1893. When the microscope stage is slightly raised, the Becke line will move towards the medium with the higher refractive index. Conversely, when the stage is lowered, the line will move towards the medium with the lower refractive index. The Becke line test is commonly used in forensic science to identify and compare glass particles based on their refractive indices. It is a simple, non-destructive technique that can help determine the source and origin of glass evidence in criminal investigations.

Answer: D. Cement block

Explanation: Compressive strength analysis is a mechanical test performed to measure the maximum compressive load that a material can withstand before fracturing. It is commonly used to evaluate the strength and quality of construction materials such as concrete, cement, brick, and stone. In the case of a cement block, compressive strength analysis is crucial to ensure that it meets the required standards and can withstand the expected loads in a structure. The test involves applying a gradually increasing compressive force to a sample until it fails, and the maximum load sustained is recorded. Compressive strength is expressed in units of pressure, such as megapascals (MPa) or pounds per square inch (psi). This analysis is not relevant for paint smears, hair, or footprints, as these materials are not subjected to significant compressive forces in forensic contexts.

Answer: D. CaO

Explanation: Borosilicate glass is a type of glass that primarily consists of silica (SiO2) and boron trioxide (B2O3). It is known for its high tolerance to thermal shock, chemical resistance, and low coefficient of thermal expansion. The typical composition of borosilicate glass includes silica (70-80%), boron trioxide (7-13%), and other minor components such as aluminum oxide (Al2O3), sodium oxide (Na2O), and potassium oxide (K2O). These additives help to improve the mechanical strength, durability, and workability of the glass. However, calcium oxide (CaO) is not a common component in borosilicate glass, as it can interfere with the desired properties. CaO is more often found in soda-lime glass, which is the most common type of glass used for windows, bottles, and jars.

Answer: B. Radial fracture

Explanation: The 4R rule of glass fracture, also known as Radial and Concentric Fractures (R.A.C.F.), relates to the characteristic patterns observed in fractured glass. When a glass surface is subjected to a sufficient force, it develops cracks that propagate outward from the point of impact. The 4R rule specifically refers to the Radial fractures, which are the cracks that extend radially outward from the origin of the break. These radial fractures are typically perpendicular to the glass surface and can provide information about the direction and sequence of the breaking force. Concentric fractures, on the other hand, are curved cracks that form around the point of impact and are generally less informative. Rib marks and hackle marks are microscopic features associated with the edges of glass fractures and are not directly related to the 4R rule.

Answer: D. (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)

Explanation: Paint is a complex mixture of various ingredients, each serving a specific purpose. The correct matches between the paint components and their examples are: Pigment – Titanium oxide, a white, inorganic compound used as a primary pigment in many paints; Oil – Linseed oil, a drying oil derived from flax seeds, commonly used as a vehicle in oil-based paints; Drier – Zirconium naphthenate, a metallic soap that accelerates the drying and hardening of paint by promoting oxidation and polymerization of the oil; Binder – Soya alkyd resin, a synthetic resin made from soybean oil and phthalic anhydride, used to bind the pigments and provide adhesion, durability, and gloss to the paint film. Understanding the composition and characteristics of paint ingredients is essential for forensic paint analysis and comparison.

Answer: A. Geiger Muller Counter

Explanation: The Geiger Muller Counter, also known as a Geiger counter, is a radiation detection and measuring instrument used to detect and quantify ionizing radiation, such as alpha particles, beta particles, and gamma rays. It consists of a Geiger-Muller tube, which is a gas-filled tube with a central electrode and a high voltage applied between the electrode and the tube wall. When ionizing radiation enters the tube, it ionizes the gas molecules, creating a brief electrical pulse that is amplified, counted, and displayed or recorded by the counter. Geiger counters are widely used in various fields, including nuclear physics, radiochemistry, and radiation safety monitoring. Neon tubes and photomultiplier tubes are not directly used for measuring radioactivity, while radiometric methods refer to a broader category of techniques that involve the measurement of radiation.