Remembering
What materials are left behind on a surface that form a fingerprint?
sweat oils and amino acids
Is DNA and Pollen trace or physical evidence?
trace evidence
State what the core temperature of a healthy human being is?
37 degrees celcius
Is a broken window physical or trace evidence?
Physical Evidence
Are pollens and DNA physical or trace evidence?
Trace eveidence
What chemical is used to show fingerprints on light colored surfaces?
Black Carbon powder
Identify the signs that will help you determine how long a green banana fell off the tree?
color change, odor, texture and presence of other living things.
Analyse pressure distribution on your feet as you run backwards.
Deeper impression a the front of the foot
Analyse pressure distribution on your feet as you run forward.
Depends on the person and speed. Highest pressure could be on the heel midfoot or toes.
Analyse pressure distribution on your feet as you turn quickly.
Deeper on the outter side of the foot you are turning or pivoting on.
What substance is used to show fingerprints on dark colored surfaces?
white aluminium powder
How much does the corpse body temperature change by per hour after death?
0.8 degrees celcius less per hour
Why fibers could only ever be considered circumstancial evidence?
It cannot prove that a person was at the crime scene because many people have same shirts, dresses jeans or hair types.
Proposed what happened at a crime scene if only a few fingerprints are found and all of them smudged?
Criminal tried to clean up the crime scene.
Propose what happened at a crime scene where broken furniture were found?
any form of assault (physical attack)
What can you use to show fingerprints on porous materials?
Ninhydrin
Calculate by how much the body temperature drops by for a corpse after 1 hour
36.2 degrees celcius
What is the temperature of a corpse at 5 hours of death?
33 degrees celcius
Fingerprints are rarely found on clothes. Explain why.
Clothes are made from fabrics which are porous materials. They absorb body fluids which makes it difficult to detect fingerprints on them.
CSU wear full body suits, gloves, and masks when collecting evidence that might contain DNA. Explain why.
To avoid contaminating the evidence with their own DNA.
List some 5 trace evidences that could be left behind by a criminal even after cleaning up the crime scene.
Any form of trace evidence such as cloth fibre, pet fibre, hair, DNA source etc
Explain how changes in the banana can help determine the time of death of a body?
the longer the time of death the darker the color, worse the odor, softer the tissues and more living things present.
Calculate what a coprse body temperature will be after 24 hours
17.8 degrees celcius
Compare similarities and differences between:
- wet shoes walking across concrete
-dry shoes walking across thick grease
-dry shoes walking across snow
all will leave impressions but difference will be
-concrete will produce positive prints
-grease will produce negative prints
-snow will produce negative prints
The two people in Fig 10.1.12 were both seen at the crime scene. Which one would be easy for an eye witness to identify and why?
Spiky hair man because he stands out of the ordinary and have more idetification markers such as tattoos on both arm, piericing on both ears and left eyebrow white skull on t-shirt.