Forensic Identification of Human Identity

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Questions and Answers

What is the classification of fingerprints for individuals whose fingerprint pattern features an upward rise and then a dip with no central core?

Compound

Arch (correct)

Whorls

Loop

Which type of print is described as being able to trace the pathway of individuals based on their movement?

Fingerprints

Iris prints

Footprints (correct)

Palms prints

What type of forensic identification relies on visual inspections and personal data for someone whose body is mutilated?

Visual identification

Presumptive identification (correct)

Positive identification

Circumstantial identification

Which method is utilized to determine if skeletal remains are human?

Precipitin test Signup and view all the answers

What information can be inferred from the footprint impression being on one side of the path taken?

Carrying heavy objects Signup and view all the answers

What distinguishes a complete identity from an incomplete identity in forensic identification?

Complete identity can establish full identity, while incomplete cannot. Signup and view all the answers

Which method is NOT typically used for identifying individuals in forensic identification?

Astrological signs Signup and view all the answers

What type of identification is referred to as 'legal identity'?

Identification without knowing the individual Signup and view all the answers

Which situation presents the greatest challenge for forensic identification?

Identification of victims in mass disasters Signup and view all the answers

Which of the following features is NOT considered for personal identification?

Preferred music genre Signup and view all the answers

How many comparison points are typically used to identify fingerprints accurately?

16 Signup and view all the answers

Which characteristic of fingerprints is emphasized for establishing identity?

Skin ridges and grooves Signup and view all the answers

What is a key aspect that remains unchanged in a person's fingerprints according to forensic identification?

Their structure even in cases of skin disease Signup and view all the answers

At what age does the body of the sternum unite with the manubrium?

60 years Signup and view all the answers

What physical change is generally observed around the age of 50 years?

Onset of cataract Signup and view all the answers

Which of the following methods achieves sex determination in a dead body?

Skeletal examination Signup and view all the answers

At what age does the iliac crest unite with the iliac bone?

23 years Signup and view all the answers

What is the percentage of Barr bodies observed in a male buccal smear?

0-4 percent Signup and view all the answers

What is the accuracy level of sex determination based on skeletal examination dependent on?

The amount of bones present Signup and view all the answers

At what age do the pubic ramus and ischial ramus unite?

6 years Signup and view all the answers

What does the x-chromosome form in a female that is visible microscopically?

Barr body Signup and view all the answers

Which of the following characteristics is typical for a male skull?

Well marked parietal eminence Signup and view all the answers

What distinguishes a female pelvis from a male pelvis?

Wide sacrum Signup and view all the answers

At what age does the frontal suture typically close?

At 2 years Signup and view all the answers

Which of the following statements is true regarding the obturator foramen?

It is oval in females. Signup and view all the answers

What is a common feature of male sternum anatomy?

Body length exceeding 2x manubrium Signup and view all the answers

What is the primary shape of the adult mandible?

Obtuse angle with the alveolar margin atrophied Signup and view all the answers

Which of the following describes the condition of sutures in someone aged 70 years?

All sutures are united except one Signup and view all the answers

How should the growth of the anterior fontanelle progress after birth?

Closes at 18 months after remaining at 3 fingers at full term Signup and view all the answers

At what age does the first permanent molars typically erupt?

6 years Signup and view all the answers

Which of the following teeth are specifically classified as milk teeth?

4 incisors, 2 canines, 4 molars Signup and view all the answers

What is the order of eruption for milk teeth starting from 6 months?

Central incisors, lateral incisors, first molars, canines Signup and view all the answers

At what age do the upper end of the humerus and femur ossify?

End of 1st year Signup and view all the answers

When do the lower end of the ulna and radius unite with their shafts?

At 18 years Signup and view all the answers

What is the correct order of eruption for permanent dentition?

First permanent molars, central incisors, second premolars, lateral incisors Signup and view all the answers

Which epiphysis unites with the shaft of the femur at 17 years?

Greater trochanter Signup and view all the answers

At what age does the ossification center for the calcaneus appear?

5th month Signup and view all the answers

Study Notes

Forensic Identification (Human Identity)

Forensic identity is defined as recognizing the individuality of a person, whether alive or deceased, using distinctive features that distinguish them from others.
It can be categorized as: complete (positive) where full identity is possible; incomplete (presumptive) where only certain aspects of identity can be established; and legal identity where an unknown body is identified by symbols.
Medico-legal investigators typically need to identify living people, fresh/intact corpses, decomposing bodies, mutilated/dismembered remains, and skeletonized material.
Identification of unknown individuals is crucial in situations like impersonation, cases of comatose patients without identification, mentally impaired individuals, suspects in assault/rape/murder cases, mix-ups of newborns in hospitals, and disputes over paternity.
Mass disasters such as air crashes, building fires, shipwrecks, and explosions create significant identification challenges; especially for high levels of putrefaction and mutilated bodies.

Methods of Identification

General facial appearance, personal impression, and visual identification.
Photography.
Anthropometry.
Handwriting analysis.
Eye colour.
Skin pigmentation and colour.
Hair colour and structure.
Fingerprints (dactylography), palm prints, foot prints, and lip prints.
Other external features (scars, birthmarks, tattoos, occupational stigmata, diseases).
Comparing antemortem records with the remains.
DNA analysis (blood grouping, protein complexes, haptoglobins, blood enzymes, and DNA).

Fingerprints, Palm, Foot, and Lip Prints

Fingerprints are formed by alternating ridges and grooves in the skin; specifically, in the epidermis and dermis of the distal phalanges.
Fingerprint characteristics are unique and permanent except for cases of atrophy or impairment caused by certain diseases or radiation.
Fingerprint analysis is based on unique features, such as precise ridge characteristics, and matching these to known prints, which allows for very accurate personal identification— a probability of 1/64 billion
Fingerprint identification involves comparison of more than 16 points that exhibit similar features.
Fingerprint analysis can also be performed using poroscopy.

Classification of Fingerprints

Sir Henry Galton (1892) classified fingerprints into four main types:
- Arch (approximately 6%)
- Loop (Radial 3%; Ulnar 65%)
- Whorl (approximately 25%)
- Compound (approximately 1-2%)

Foot Prints

Footprints can serve as pathways to identify missing persons or criminals.
Footprints can be analyzed for distinguishing features, like congenital anomalies, distances between prints, and the presence of different movements, such as running,carrying heavy objects etc.

Identification of Dead Bodies

Unmutilated corpses are identified using the same methods as living people, excepting gait, voice, and mental function, as well as handwriting.
Presumptive identification of mutilated corpses involves visual assessment, anthropometry, personal data (race, sex, age), blood grouping, hair color, eye color, and tattoos.
Positive identification involves comparing antemortem and postmortem records (dental records, fingerprints, palmprints, footprints, or DNA profiling).

Identification of Decomposed/Skeletalized Remains

Determining if remains are bone/human bone using anatomical analysis and the precipitin test.
Determining if remains belong to one person.
Identifying the sex of the remains (skull and pelvis characteristics).
Determining the age of the remains (skull sutures, dental analysis etc.).
Determining the height of the remains, race etc.
Determining the time since death or concealment, and
Determining the cause of death.

Identification of Sex from Bones

Skull characteristics (e.g., general size and shape, prominence of brow ridges, shape of the eye sockets, jaw size and shape).
Pelvic characteristics (e.g., subpubic angle, shape and size of the sacrum, and the shape of the obturator foramen).
Sternum.

Identification of Age from Bones

Skull (dimensions, sutures, fontanelles, mandible, and teeth).
Appearance of ossification centers.
Union of epiphyses.
Extent of the medullary cavity.

DNA Profiling

DNA profiling was described by Dr. Alec Jeffreys, a British geneticist.
DNA is highly specific to individuals due to unique, repetitive base sequences.
DNA profiling is used in forensic investigations for personal identification, parentage testing, identifying body remains, and sex/species determination.

Medico-Legal Applications of DNA Typing

Personal identification.
Parentage testing.
Identification and matching of body remains.
Determination of sex and species.

Time Since Death

Before 6 months: soft tissues are associated with the bones.
6-12 months: bones are attached by ligaments.
After one year: only bone remains.
Bones become lighter, whiter, less smelly, and more brittle over time.

Medical Imaging as an Aid for Forensic Identification

Radiological studies are used to identify ages, injuries, and unique bone structures. Suitable areas include the wrist and elbow in infancy/childhood; the pelvis, hips, shoulder, and elbow joints in adolescence; and the skull in adulthood/old age.

Height and Weight Data

Age determination based on height and weight tables according to age and sex.
Height determination using span (between outstretched fingertips).
Height determination via formulas based on bone measurements (e.g., femur = 25% of height, humerus= 18% of height).

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Description

This quiz explores the concept of forensic identification, including the definitions and categories of identity recognition for both living and deceased individuals. It covers the importance of identifying unknown persons in various scenarios, such as legal cases and mass disasters. Test your knowledge on this critical forensic topic.