Forensics Death
cause of death
-Asphyxiation -blunt force trauma -drowning
How does rigor moritis work?
-At death ATP reserves are used up quickly and calcium can't get shipped out the cell... it builds up inside. -calcium build up causes muscle fibers to link and stay linked
Black putrefaction- 10 to 20 days post mortem
-Bloat collapses, skin recedes, body looks black and area around body is wet. Very foul smell.
What is still alive even though a person is pronounced dead?
-Skin cells can be harvested for up to 24 hours - Bacteria in your intestines
What happens a month after death?
-The hair, nails, and teeth start to fall out
What could change the decomposition rate of a body?
-being mummified -being embalmed -being buried
manner of death
-homicide -suicide -natural -accident -unknown
Who gets and autopsy?
-injury -delayed complications of injuries -poisoning -infectious complications -foul play -people who die with no attending psysician
Where do blow flies deposit its eggs?
-natural openings of body: mouth, ear, nose -open wounds
What happens to internal organs and tissues when an individual dies?
-organs and tissues will liquify which will swell the body until it bursts open
What happens a week after death?
-skin has blistered and the slightest touch could cause it to fall off
Stages of Death
1. Somatic 2. Molecular
How long does rigor mortis last?
10 minutes to several hours
What length is the second instar?
10mm
When is the maximum stiffness reached during rigor mortis?
12-24 hours post mortem
How long can skin cells be harvested after a person is pronounced dead?
24 hours
How many eggs to blowflies deposit at one time?
300 eggs
What is the normal body temperature?
98.6 degrees
What happens during the first hour of algor mortis?
A body cools very little during the first hour of post mortem
What is the vitreous humor?
A clear gel that fills the space between the lens and the retina of the eye.
What muscle fibers link and stay linked when calcium builds up during rigor mortis?
Actin and Myoscin
Third stage of a fly?
Adult
What happens after the first hour of algor mortis?
After the first hour to about six hours, a body will generally cool at a rate of 1.5 degrees for each hour after death
Dry decay- 50-365 days after death
Body is dry and decays slowly to bones
Stage of Death: molecular
Breakdown of the body (decomposition)
Posterior spiracles
Breathing
What is "Tache noir"?
Brown corneal surface from exposure to the environment
What happens if eyes were closed at death?
Corneal film appears in several hours
What happens if eyes were open at death?
Corneal film appears within minutes
What does necrophagous mean?
Corpse eating
What is the body of a maggot designed for?
is designed for sucking and slurping
What does the front end of a maggot do?
it has mouth hooks with which tear decaying flesh.
If a body is found dead on top of rocks or iron what will lividity look like?
lividity will pattern based on the texture the body is lying on
What is the normal color of lividity?
maroon color
Medical examiner
medical doctor with specialized training in pathology
Livor
Discoloration
What are instars?
Each of the stages between molts -there are three instars
What do anterior spiracles do?
Eating
What is first affected during rigor mortis?
Facial muscles are affected first, with the rigor then spreading to other parts of the body.
Where is the anterior of the maggot?
Front end (smaller end)
What is produced as bacteria eats tissue?
Gas is produced which causes the body to bloat
Livor mortis
Heart stops beating and/or lungs stop breathing Body cells no longer receive supplies of blood and oxygen Blood drains from capillaries in the upper surfaces and collects in blood vessels in the lower surfaces Upper surfaces of the body become pale and the lower surfaces become dark
What does the rear end of a maggot do?
It consists of their anus and posterior spiracles
First stage of a fly?
Larva (maggot)
What do bacteria in a persons intestines who is dead lead to?
Leads to putrefaction or decomposition
Progressive Approach: Higher brain standard
One dies when in a state in which the brain is incapable of returning to consciousness Person in a vegetative state or in a permanent coma is dead Death is the irreversible stopping of the capacity for consciousness Dreaming, dreamless sleep or reversible coma
What is the outside of a spircle called?
Peritreme
What happens to the vitreous humor at death?
Potassium starts to leak out the vitreous humor of the eye at a known rate.
Second stage of a fly?
Pupa
Where is the posterior end of a maggot?
Rear ends
What is Rigor Moritis?
Stiffening of the body after death.
What happens to the sclera overtime?
Tache noir occurs over time
What is algor mortis?
The rate at which the body cools.
How do maggots move throughout the corpse?
They move by secreting digestive enzymes and spreading putrefying bacteria.
What do maggots produce?
They produce heat, which can raise the temperature around them more than 10 degrees Celsius
at the crime scene how do they measure the temperature?
Through the liver
What does TOD stand for?
Time of Death
Where is the National Geo Body Farm located?
University of Tennessee
When is lividity a cherry red color?
When cause of death is carbon monoxide poisoning
Oldest approach to death: Cardiopulmonary standard
When lungs and heart stop permanently Check for a pulse, moisture on a mirror held in front of the mouth... If none, must be brain dead as well With the development of modern life support machines, a working heart and lungs may not indicate brain stem function.
Stage of Death: Somatic
When vital bodily process stop (Breathing, digestion, energy production, heart beat)
4-10 days Post mortem
body bloats from gas build-up. Gases released: hydrogen sulfide, methane, cadaverine, and putrescence
mortis
death
How can lividity tell you if the body was moved?
if lividity appears on the front of the body but corpse is on its back
What is the most accurate means of taking body temperature?
rectal
What is the length of the 1st instar?
roughly 2 mm to about 5 mm
How long does an autopsy take?
an hour
Lividity
appears in hues of red during livor mortis
coroners
are elected
What happens a few days after the death of a body?
bacteria and enzymes start to breakdown the host's tissue -bacteria works its way to the organs of the body, turning it colors and producing a foul smell
Initial decay 0-3 days post mortem
bacteria breaks down organs
Whats the length of the 3rd instar?
between 15mm to 20mm
Butyric fermentation- 20 to 50 days PM
-All remaining flesh is removed and the body dries out. -It has a cheesy smell caused by butyric acid -The surface of the body that is in contact with ground becomes covered in mold
Problems with algor mortis?
-Age -weight -illness -alcohol -conditions of environment (temperature, clothing, surface, activity -drugs
Current Mainstream approach: whole brain standard
Death is the permanent stopping of the function of the entire brain, including the brainstem. A machine that keeps your heart beating and lungs breathing... Not Alive Permanent vegetative state is ALIVE because a functioning brainstem enables respiration and circulation.
What does putrefaction mean?
Decompositon
What happens to the sclera during the early stages of post mortem?
Will be relatively clear
