unit 8: death, entomology, and anthropology

Question 1

cause of death:

Answer 1

the injury or condition responsible for a person’s death
ex. disease, injury, stroke, poisoning, or heart attack

Question 2

mechanism of death:

Answer 2

the specific psychological, physical, or chemical event that stops life
ex. blood loss, loss of oxygen (asphyxiation)

Question 3

manner of death definition:

Answer 3

determination of how injury or disease leads to death

Question 4

manners of death:

Answer 4

1. natural
   -> interruption and failure of body functions resulting from age or disease
2. accidental
   -> death caused by unplanned events
3. suicidal
   -> death caused by oneself
4. homicidal
   -> the death of one person intentionally caused by another person
5. undetermined

Question 5

body changes after death:

Answer 5

1. heart stops
   -> blood is no longer pumping
   -> stops delivery of oxygen and glucose
2. cells produce less energy
   ->lack of oxygen and glucose leads to less energy available for cells
3. anaerobic respiration
   -> less energy is produced and lactic acid builds up
4. cells rupture
   -> toxic wastes accumulate
   -> cell membranes rupture and cytoplasm seeps out of cells

Question 6

autolysis:

Answer 6

cellular enzymes are released inside the cell that break down the cell contents and rupture the cell membrane, destroying the cell

Question 7

PMI:

Answer 7

post mortem interval

Question 8

TOD:

Answer 8

time of death

Question 9

Algor Mortis

Answer 9

-> the cooling of the body after death
-> temperature of body can be used to determine post mortem interval
-> temperature should be taken from the liver or rectum
-> body will lose heat to surroundings until it reaches ambient temperature
-> body cools at a rate of 1.4 F per hour for the first 12 hours
-> 0.7 F per hour after

Question 10

Livor Mortis

Answer 10

-> lividity becomes visible appx. 2 hours after death and becomes permanent after 8 hours
-> results from gravity and can reveal position of body during first 8 hours after death

Question 11

lividity:

Answer 11

the reddish-purple color that results after break down of blood vessels and release of hemoglobin

Question 12

Rigor Mortis:

Answer 12

-> death stiffness
-> in order for muscles to relax, calcium is released, without oxygen and the production of energy a person in the process of death cannot relax their muscles
-> muscles will become rigid within 2 hours of death
-> muscles will then relax after autolysis of cells, appx. 48 hours after death

Question 13

factors to consider when determining PMI:

Answer 13

-> a person’s body mass relative to surface area (weight)
-> body position
-> clothing on the body
-> environment/ambient temperature
-> level of physical activity
-> autopsy

Question 14

autopsy:

Answer 14

medical examination to determine the cause and manner of death

Question 15

clinical autopsy:

Answer 15

performed for medical research purposes when foul play is not considered
ex. a person in good health dies unexpectedly

Question 16

forensic autopsy:

Answer 16

performed when foul play is suspected
-> state laws vary regarding when an autopsy is required
-> all states require autopsies for deaths due to injuries, poisoning, unusual infections, and foul play
-> suspicious deaths are reported to the coroner or medical examiner that determines if an autopsy is needed
-> an external and internal examination is performed and documented

Question 17

stomach and intestinal contents:

Answer 17

-> 2-6 hours for the stomach to empty its contents
-> 12 hours for the food to leave. the small intestine
-> 24 hours from time of meal was eaten until waste is eliminated through the rectum

Question 18

postmortem changes in the eye:

Answer 18

-> potassium builds up in the eye leading to a cloudy film
-> film is observed within 2-3 hours if the eye is open
-> observed within 24 hours if the eye is closed
-> buildup of potassium could be used to estimate TOD, this method is not considered reliable yet

Question 19

stages of decomposition:

Answer 19

1. several hours after death
2. after several days
3. days 7-23
4. after 3 weeks to 2 months
5. after 2 months

Question 20

stage of decomposition: several hours after death

Answer 20

-> cell autolysis
-> loss of muscle tone
-> bladder and rectum empty
-> onset of algor, livor, and rigor mortis
-> cloudy film forms over the eyes
-> flies arrive to deposit eggs on body

Question 21

stage of decomposition: after several days

Answer 21

-> blistering of skin and internal organs results in skin slippage
-> putrefaction begins (destruction of soft tissues due to bacteria)
-> abdominal swelling due to release of CO2 from anaerobic respiration
-> marbling of skin occurs
-> internal pressure from fluids may force fluids from body openings
-> loss of rigor mortis
-> increased insect activity

Question 22

stage of decomposition: days 7-23

Answer 22

-> bloating continues as more gases are released from the body
-> discoloration of skin may make ID of skin color impossible
-> ruptures in skin occur- more seepage of fluid- increased bacterial and insect activity
-> soft tissues start to liquify

Question 23

stage of decomposition: after 3 weeks to 2 months

Answer 23

-> greatest loss of mass due to insect infestation, bacterial action, and purging of fluids
->fats start to decompose forming greasy wax or adipocere
-> adipocere prevents oxygen from reaching underlying tissues which can preserve tissue

Question 24

stage of decomposition: after 2 months

Answer 24

-> soft tissues are usually done
-> bones remain
-> odors are mostly gone

Question 25

entomology:

Answer 25

the study of insects and other arthropods (spiders)

Question 26

forensic entomology:

Answer 26

- interpretation of that insect evidence in criminal and civil investigations - provides an estimate of min and max time that could've passed since colonization (of the insects)

Question 27

what are the forms insect evidence can be found in?

Answer 27

- adults - pupae - larvae - eggs - insect body parts

Question 28

general decomposition stages:

Answer 28

1. fresh (2 days)- warm, newly dead body 2. bloated (1 week)- a corpse emits odors of decaying flesh 3. decay- a body emits gases of decay with strong odors, and shows signs of darkened tissues 4. dry/skeletal decay- mostly bones remain

Question 29

bacteria produces two gases:

Answer 29

putrescine and cadaverine

Question 30

Blowfly life cycle: <8 hours after death

Answer 30

blowfly eggs found in moist, warm area of corpseshour

Question 31

Blowfly life cycle: within 20 hours after death

Answer 31

1st of the 3 larva stages

Question 32

Blowfly life cycle: 4-5 days after death

Answer 32

3rd of the larva stage

Question 33

Blowfly life cycle: 8-12 days after death

Answer 33

larvae migrates to dry places

Question 34

Blowfly life cycle: 18-24 days after death

Answer 34

early pupa; changes from light brown to dark brown; immobile

Question 35

Blowfly life cycle: 21-24 days after death

Answer 35

pupa case splits open and adult blowfly emerges

Question 36

insects can help to determine ___.

Answer 36

postmortem interval

Question 37

environmental conditions that impact insect growth:

Answer 37

1. temperatures 2. time of day (egg laying doesn't happen at night) 3. rainfall/precipitation

Question 38

two collections of evidence:

Answer 38

1. collect live insects 2. preserve other insects at scene

Question 39

collect ___ first. collect ___ and ___ second

Answer 39

adults; larvae and eggs

Question 40

after the body is removed, you should collect insects from ______

Answer 40

surrounding soil

Question 41

what else can affect timing/development of insect life cycles

Answer 41

certain drugs; makes TOD analysis more difficult

Question 42

___ drug speeds up development and ___ drug slows down development

Answer 42

cocaine; arsenic

Question 43

what are bones?

Answer 43

framework for our body, anchor our muscles, allow movement, and protects vital organs

Question 44

bones contain what along with living bone cells?

Answer 44

calcium and phosphate

Question 45

infants are born with ___ bones that fuse into the ___ bones in an adult body

Answer 45

270; 206

Question 46

ossification:

Answer 46

the process of bones replacing cartilage

Question 47

ossification begins before ___ and continues for more than __ years

Answer 47

birth; 50

Question 48

during childhood bones thicken, ___, and grow longer

Answer 48

ossify

Question 49

after age __, bones lose ___ faster than they are built

Answer 49

30; minerals

Question 50

what do bones contain?

Answer 50

"diary of injuries, disease, and nutritional deficiencies

Question 51

what diseases are easily observed in bones?

Answer 51

osteoarthritis and osteopreosis

Question 52

what is rickets caused by?

Answer 52

lack of vitamin D resulting in bowel legs, thinner skull, and deformed spine

Question 53

what is anemia caused by?

Answer 53

lack of iron results in holes in the eye socket and skull

Question 54

breaks that occur in advanced stages of decomposition snap off ___

Answer 54

easily

Question 55

what is present in bones and can be tested?

Answer 55

different isotopes

Question 56

what dissolved element is found in groundwater?

Answer 56

strontium

Question 57

after ingestion, strontium is deposited in ___

Answer 57

teeth

Question 58

food contains different amounts of stable ___ and ___

Answer 58

carbon-13 and carbon-12

Question 59

after ingestion, these isotopes are absorbed into the ___

Answer 59

bone

Question 60

male differences:

Answer 60

- frontal bone is low and sloping - eye orbits are more square - lower jaw (mandible) has an angle closer to 90˙ - pelvic cavity is heart shaped - sacrum curves inward

Question 61

female differences:

Answer 61

- the subpubic angle is greater than 90˙ - female pelvic cavity is oval shaped - shorter tailbone - sacrum curves outward

Question 62

age can be determined by what?

Answer 62

- number of bones - degree of ossification - presence or absence of growth plates - degree of wear on bones - teeth - skull sutures

Question 63

it is difficult to determine ___ from skeletal remains

Answer 63

ancestry

Question 64

prognathism:

Answer 64

projection of maxilla and/or mandible beyond the face