Time of Death/Postmortem Changes Flashcards
What are the three major mechanisms of heat loss?
AR
conduction, radiation, convection
What is conduction?
AR
transfer of heat by direction contact to another object
What is radiation?
AR
transfer of heat to the surrounding air
What is convection?
AR
transfer of heat through moving air currents
What is the light area (void) called in lividity?
AR
Blanching
What are the stages of human decomposition?
MH
Fresh, bloat, active
decay (purge), advanced decay, and dry remains
An extreme simplification of why we have decomposition?
MH
physiological changes which cause degradation and
liquefaction of soft tissues.
VERY IMPORTANT NOTE - about children and postmortem changes.
MH
Children are not small adults – their rate can be very different
T or F: Rigor mortis, Livor mortis, and Algor mortis tell you the exact time of death when applied together ?
MH
F (false)
T or F: The longer lenght of time someone is deceased, the more difficult it becomes to estimate time of death.
MH
T (true)
True or False: Lower environmental temperatures accelerates the pace at which Rigor Mortis Sets in.
False, Higher environmental temperatures accelerate Rigor Mortis setting in.
(KW)
How does Rigor Mortis appear in the body?
It starts setting in with the small muscles first, and then moves onto larger muscles over time.
(KW)
What is Autolysis?
The Aseptic breakdown of cells and organs caused by intracellular enzymes.
(KW)
What is Putrefaction?
The breakdown of cells and organs due to bacteria and fermentation, and is when smells start to appear.
(KW)
True or False: Injuries can still be seen in states of advanced decomposition.
True
(KW)
What color does carbon monoxide poisoning turn the skin?
Cherry red
(CG)
What are Tardieu spots?
Dark spots on a persons body as a result of capillaries bursting under pressure.
(CG)
What is Adipocere?
Partial preservation as a result of the hydrolysis or saponification of body fat.
(CG)
Which forensics field is most useful when determining Time of Death?
Forensic Entomology
(CG)
What insect artifact is commonly confused with high velocity blood spatter?
Fly spatter
(CG)
What is a postmortem artifact?
Different aspects at a scene that may cause someone to think something different. An example being a red substance around the head, but it isn’t blood, the body is just leaking fluid.
(NA)
What is the most reliable way to determine PMI?
Insects
(NA)
What can affect the stages of decomposition?
Temperature, moisture, injuries, clothing, location of body, animal and insect access, illness, and/or body composition
(NA)
What are some decomposition accelerants?
High body temp, high environmental temp, heavy clothing, obesity, sepsis, and injuries
(NA)
What are rigor mortis retardants?
cold temperatures and thin/weak people since they have low amount of muscles.
(NA)
What is most commonly used when determining the time range of death? HS
Rigor mortis and algor mortis
T or F: Bloating can cause limbs to be in a strange position after rigor sets in? HS
True
What is a degloving? HS
When the skin on the hands or feet slide off
What is slippage? HS
When the skin begins to slip off the body during decomposition
What do areas of pressure on the skin look like in lividity? HS
White/blanched (ex. a belt around the waist)
