forensics 9 weeks exam
describe how information is processed in the brain.
Information processing starts with input from the sensory organs, which transform physical stimuli such as touch, heat, sound waves, or photons of light into electrochemical signals. ... In order for the brain to process information, it must first be stored.
Where does rigor mortis start?
a) In the smaller muscles and progresses to the larger muscles
Define diatoms.
a) Nonvascualr photosynthetic organisms. Relatives of algae that have cell walls containing silicon dioxide.
Which method of estimating postmortem interval is least reliable if a person has been dead less than 12 hours?
c. potassium levels in the eye
the wheelbase measurement is the distance between the....
center of the front wheel and the center of the back wheel
which of the following is the finest of all soil textures?
clay
Which of these definitions are correct? Mark all that apply.
d) All the above
t/f: Adipocere is a waxy material formed from the breakdown of fat during decomposition under very dry conditions.
false
t/f: Body heat loss speeds up after 12 hours following death.
false
t/f: Once skin slippage begins, it is impossible to obtain fingerprints.
false
t/f: PMI stands for personal myspace interaction
false
t/f: Usually, children will lose body heat more slowly than adults.
false
t/f: because bones can heal, a bone fracture is no longer evident after 10 years
false
t/f: center of the tread of a tire to the center of the tread of the opposite tire is the wheel base.
false
t/f: good observation skills come naturally to investigators; they do not need to be trained
false
t/f: if we remember seeing something happen, we can trust that it happened just as we think it did
false
t/f: if we remember seeing something happen, we can trust that it happened just the way we think it did
false
t/f: if you can measure the length of the foot or shoe impression, then you can accurately estimate the person's height
false
t/f: in court, a lawyer must be able to fit the tool into the tool marks to convince a jury that they are consistent
false
t/f: insect evidence is the most accurate method to estimate a postmortem interval if the victim has been dead less than 24 hours
false
t/f: instars are each of the different pupa stages
false
t/f: mitochondrial dna analysis of skeletal remains can be used to establish individual identity
false
t/f: observation skills are only helpful to the investigator at the scene, nowhere else in forensic science
false
t/f: the chainsaw with missing serial number was enough to convict Richard Craft
false
t/f: the innocence project is an organization that seeks to get convicted killers out of prison
false
t/f: the number of bones in the body increases from the time of birth to adulthood
false
t/f: tool marks are direct evidence
false
t/f: when we observe something in our day to day lives we view things null of preconceived notions
false
t/f:information is a constant, unvetted stream into the brain where it is stored
false
Round eye orbits, large subpubic angles, oval pelvic cavity, and a smooth & slender skull. Male or Female?
female
Short sacrum curves out, no protuberance on occipital bone, triangular underside of lower jaw. Male or Female?
female
Wide subpubic angle, sacrum curved outward, no visible growth plates, porous bones. What is the gender and condition?
female over 30 with osteoporosis
which represents the normal sequence of decomposition?
fresh, bloated, active decay, advanced decay, dry decay
What is not used for bone connection?
growth plates
Remains from a small person had no indicators of sex. Explain this.
has not reached puberty
which of the following represents an undisturbed soil profile, starting at the surface?
humus, topsoil, sand and silt, subsoil, broken rock, solid rock
a forensics scientist will exam a tread and impressions for what two characteristics?
identifies the type of tire and model of a vehicle
what helps link a tool to a crime scene and eventually to the tool's owner?
impressions or scratches
the innocence project found that most faulty convictions were based on...
inaccurate eyewitness accounts
is indirect or direct lighting better for photographing tool marks?
indirect
what type of evidence does forensic entomology use?
insect
why do eyewitness accounts carry such larger weight in the courtroom?
juries think of them as large pieces of evidence
when a shoe or barefoot walks on a smooth surface it usually leaves a...
latent print
Narrow pelvis, sloping frontal bone, and prominent protuberance on occipital bone. Male or Female?
male
briefly describe what can be detected by observing facial expressions.
muscle movements can determine if you're lying or not
Which is the most reliable bone to determine the sex of a skeleton?
pelvic bone
the three steps in collecting impression evidence are...
photographing, lifting latent impressions, and casting plastic impressions
loam is a fertile type of soil composed of approximately equal amounts of what?
sand and silt
the stench of decomposing bodies can attract trained cadaver dogs to bodies in what type of graves?
shallow graves
which description below would most likely indicate the presence of a recent gravesite?
soil level raised, no plant life on surface
what variations identify different tools?
specific tool marks
tire marks indicate...
speed of vehicle and the direction that the vehicle traveled
what kinds of factors might affect an eyewitness observation?
stress
how do we account for our brain's inability to collect every detail of the scene?
systematic scanning
which of these does not affect the development of insects?
technology
What connects a muscle to a bone?
tendons
How do forensic investigators determine the size, shape, and other characteristics of a tool?
the impressions
What is the growth plate responsible for?
the lengthening of the bone
what are the ribs on a tire?
the ridges around the circumference of tire
patent impressions appear after...
the vehicle has been driven through a fluid like substance
"Plants provide a biological clock that provides evidence as to when a person died, or the postmortem interval"(T/F
true
A limitation of forensics botany is that all living matter decomposes quickly (T/F)
true
Annual rings are formed as a result of differences in color of the lighter springwood and the darker winterwood. (T/F)
true
Knowing ancestry and sex make height estimations more accurate. True or False?
true
The first time botanical evidence was accepted in court was in 1932. (T/F)
true
When obtaining botanical evidence, a paper bindle is the correct method of collection. (T/F)
true
Why botanical evidence is often overlooked because The criminal does not often take into consideration if they are transferring plants from one habitat to another. (T/F)
true
t/f: A person who was running away from someone before he or she died will go into rigor mortis sooner than a person who was sitting quietly.
true
t/f: An autopsy is performed after an unexplained death to help explain the cause and manner of death.
true
t/f: Cloudiness of the eyes occurs usually after two hours if the eyelids are open.
true
t/f: Internal pressure from fluids and foul smelling decomposition gases force fluids from body openings after several days of death.
true
t/f: a blowfly's host can affect the development period of a larva
true
t/f: blowflies are attracted to dead bodies because of the oder
true
t/f: bones break unevenly when alive but evenly when body has been dead a while
true
t/f: cadaver dogs find bodies due to the odor of gases emitted during decomposition under anaerobic conditions
true
t/f: forensic entomology can be used to find the identity of a corpse
true
t/f: forensic entomology can determine if a body was moved
true
t/f: forensic investigators use databases of tool marks to determine the type of tool used in a crime
true
t/f: from tire marks left on pavement, it is possible to estimate the speed of a vehicle at the time it began breaking
true
t/f: handsaws and hacksaws can result in overlapping cuts?
true
t/f: high moisture levels in soil stimulate the formation of adipocere
true
t/f: if you find a body and only mostly bones remain it is in a stage of dry decay
true
t/f: investigators can find out the indentity of a body via what stage of decomposition the body is in
true
t/f: it is impossible to cast an impression in the snow if you use a casting material that does not generate heat
true
t/f: knowing the sole pattern on a shoe may enable investigators to identify the shoe's manufacturer
true
t/f: perception is not always accurate, and it does not reflect reality
true
t/f: soils are mixtures of materials formed from weathered rocks, water, air, and decomposing organisms
true
t/f: spiracles allow researches to determine if the fly is in the first, second, or third instar
true
t/f: the brain cannot process and remember every detail of a crime scene
true
t/f: the crop can contain dna of a victim
true
t/f: the hacksaw creates a bone mark pattern of a tic tac toe board with thousands of squares?
true
t/f: the word forensic refers to the application of scientific knowledge to legal questions
true
t/f: tire scrubs are produced by tires during impact
true
t/f: wasps arrive after blowflies because they feed on blowfly larvae and eggs
true
t/f: when estimating a postmortem interval, its most important to factor into the interval the face that flies and beetles don't lay eggs at night
true
which of the following does not affect what happens to the buried decomposing body?
weather
What questions do Forensic Anthropologists ask?
what was the cause of death?
Can tooth development help determine age?
yes
how many stages are there in the life of a larvae
3
what are the roles filled by a forensic scientist?
CSI
what marks are made by a tool when surfaces slide across one another?
a) abrasion marks
messy cuts with rough edge teeth marks can be expected from which saw?
a) chain saw
what is the strykers cut characteristics?
a) circular areas with short radii
what does the casting material used depend on?
a) climate and type of surface
what kind of microscope is used to compare photos of tool marks?
a) comparison microscope
what is used to lift latent impressions?
a) electrostatic dusting
ridged grooves in the bone result from which kinds of saws?
a) table saw
Define autolysis and putrefaction
a. Autolysis cause cells or tissues to be destroyed by their own enzymes. Putrefaction causes destruction of soft tissues due to bacterial activity beginning.
As you drive along a roadside, you and your friend notice a dead deer. Your friend comments that the deer must have been pregnant. "Did you see the size of its belly? It was huge!" what other explanation could you give your friend as to why the abdominal region of the deer was so large?
a. Due to several days of the deer's death, anaerobic bacteria of the intestines consume tissues and release carbon dioxide to cause bloating
State the cause, manner, and mechanism of death when a teenager was found dead after consuming alcohol and heroin together.
a. Overdose (poisoning), accidental, respiratory functions cease
Which can issue death certificates but cannot perform autopsies?
a. coroner
Round nasal cavity, rectangular eye orbits, some degree of prognathism. What is the ancestry?
african
Why do Forensic Anthropologists look at bone caps, bone shafts, growth plates, & sutures?
age
what tools do detectives use to secure details about a crime scene?
all of the above (photographs, a field notebook, and a ruler)
what type of enviorment produces the gases cadaverine and putrescine due to the decomposition of body proteins?
anaerobic respiration
the femur head is fused to the shaft, the clavicle sternum, lamboidal structure, and coronal suture are closed. what is the age range?
at least 50
What can you concur when a body is found with lividity and the redness disappeared after the skin was pressed?
b) Death occurred between 2-8 hours earlier
What evidence was used to make a conviction in the Lindbergh kidnapping case?
b) Ring marks in a ladder at the crime scene.
what should you focus on when looking at tool marks?
b) foreign marks
what marks are made by a tool when it is pressed against a softer surface?
b) impression marks
what should be done before casting?
b) photograph evidence
when processing a crime scene for impression evidence, which of the following steps should be taken first?
b) photograph the impression
Marbling occurs as a result of?
b. Chemical reactions of sulfur and hemoglobin
what is the second stage of decomposition?
bloated
In the sequence of events of death, what event comes after the cell membranes rupturing?
c) fluids escape
what information can be learned from skid mark analysis of an accident?
c) when brakes were applied
Which statement about the rate of decomposition is generally used?
c. A buried body decomposes more slowly than a body that is not buried
What are the two types of autopsies?
d) Forensic and clinical
What are the differences between botanical evidence collection and habitat sampling?
d) Habitat sampling specifically compares plants from the crime scene and neighboring habitats to determine any transfers.
Botanical evidence is a valuable source of evidence because ________.
d) It tells you when and where a crime was committed.
what additional evidence can a barefoot print provide?
d) all of the above
the depth of an impression can estimate...
d) both B and C (height and weight)
The body of a person known to have eaten Mexican food at 12 noon was found dead at 11 P.M. The examiner found no food in the stomach but did find evidence of Mexican food in the first half of the small intestine. Based on the postmortem interval (PMI) estimate from the stomach contents only, which of the following times would be the best estimate of a PMI.
d. between 4pm and 11pm
What is an example of how technology has advanced tool mark evidence?
database, HD photography, measuring tape
what is used to make a plastic impressions in the snow?
dental stone
what does the turning diameter of a vehicle indicate?
diameter of the smallest 360 degree circle that can be driven by a vehicle 2. determines how vehicle was driven and the level of inflation
describe why two people might perceive a crime scene in different ways.
distractions/ see things from different angles
what is the corrected developmental stages for blowflies?
egg, larva, pupa, adult
a forensic scientist is called to a court of law to provide...
facts
After 72 hours, Gastric Contents from the victim's stomach allow you to determine if they have consumed fruits and vegetables. (T/F)
false
An newer gravesite sinks into and fills the grave as the ground settles. (T/F)
false
If there are no scars on a woman's pelvis, she definitely hasn't had kids. True or False?
false
Pollen present on the victim that is consistent with the pollen from a suspect provides strong evidence that the suspect is guilty. (T/F)
false
