Forensic Science

Question 1

What is most useful for Sex Discrimination ?

Answer 1

Skeleton - pelvis and skull

then either prostate or uterus

Question 2

Indicator of ageing from infancy to adulthood

Answer 2

examining the teeth

Question 3

Determination of age - Childhood and adolescence

Answer 3

epiphyses

Question 4

… are very useful in determining foetus and neonate (age)

Answer 4

X-rays

Bone development assessment using ossification centres
24 GW (Gestation Weeks) and term are of most frequent interest

Question 5

…. are most useful for calculation of height

Answer 5

Individual bones of the lower limb

long bones - good

Question 6

In a Mass Fatality Incident, maximum benefit can be gained by helping investigators…..

Answer 6

reconstruct the incident

Question 7

Death is defined as

Answer 7

the irreversible failure of the CVS

Question 8

Can the rate at which the stomach empties be used as a means of measuring the time of death - or the time since the last meal?

Answer 8

No

Too many factors influence the rate at which the stomach empties, e.g. nature/amount of food, solids vs liquids, stress, certain medication

Can offer information on what the deceased last ate depending on the condition of the material remaining

Stress can prevent stomach emptying

Question 9

Stiffening and shortening of muscle fibres leading to rigidity of the musculature and fixation of the joints

Answer 9

Rigor Mortis

reduction of adenosine triphosphate (ATP) within the muscles after death

calcium builds up in the muscles, causing them to tense

therotecically detected in smaller muscles before larger muscles

becomes apparent 5-7 hours after death
usually full established by 8-12 hours
36 hours after death - body in flaccid state

Question 10

A process of “dry” decomposition, with desiccation of the body and a relative lack of bacterial involvement

Answer 10

Mummification

Body essentially “dries out”; the facial features and hands/feet may become rigid
Preservation may be remarkable
Infant bodies particularly prone to mummification

Question 11

Caused by the action of bacterial micro-organisms; process begins at death, but takes a period of time to become detectable

Answer 11

Putrefaction

rem by (petri - bacterial)

Question 12

Induced by the hydrolysis of fatty tissue within the body into a greasy/waxy or brittle material which frequently remains attached to the bony skeleton and may retain the body structure to some extent

Answer 12

Adipocere formation

Tends to occur in damp or wet environments, e.g. bodies recovered from water

Question 13

The condition when all of the soft tissues of the body have completely degraded

Answer 13

Skeletonisation

The process is extremely variable: main variables are exposure to meat-eating animals (post mortem animal predation, e.g. rats) and to dipterous larvae
Radioisotopes have been used to “age” bones, recently including strontium and polonium

Question 14

Represents the pooling of Stagnant blood in dependent regions of the body under the influence of gravity

Answer 14

Post mortem hypoStatis

Usually readily apparent on the external aspect of the body, but may also be observed in the internal organs

Begins as soon as the circulation of blood ceases, but takes time to become visible, usually about 1-2 hours, and fully established by 6-12 hours

not for timing death

Question 15

hypostasis (Red/brown) - may be seen with

Answer 15

methaemoglobin (caused by certain chemicals or drugs)

Question 16

hypostasis - Cherry red colour

Answer 16

indicator of carbon monoxide poisoning

Question 17

Colour of hypostasis can occasionally be

Answer 17

Usually pink/purple in colour

Question 18

Alteration or damage to the body occurring after death which may mimic genuine processes occurring in life

Answer 18

Post mortem Artefacts

• Resuscitation (cardiopulmonary resuscitation - CPR)
• Animal predation (land and sea)
• Traumatic injury

Question 19

cooling - room temp - 1C every hour (sigmoid curve)
circulating blood becomes stagnant - falls under gravity - 1-2 hours
putrefaction - process begins at death, detectable in days
rigor mortis - begins 5-7 hours
skin shrinks
body green 2-3 days
blister formation and tissue swelling - gas formation 1 week

Answer 19

stages of death

Question 20

gold standard comparative methods

Answer 20

fingerprint
dental records
DNA

med information

Question 21

oppportunity for timing of death

Answer 21

first 18 hours

Question 22

measurement of core body temp

Answer 22

first 12 hours

Question 23

timing of death - aL-Alousi and Henssge

Answer 23

accuracy of no better than +/- 2.5 hours

precise timing not possible