3 TEST Flashcards
(64 cards)
What is DNA ?
The instruction manuel that tells each cell of your entire body what to do.
Where is DNA found ?
In every cell of your body
Where does DNA come from ?
It comes from your mom’s egg and dad’s sperm ( 23 chromosone each)
What are the four chemical units of DNA?
A (Adenine), G (Guanine), T ( Thymine), C ( Cytoisne)
How to extract DNA from a sample ?
1 : Collect the cells
2 : Break the cell membrane ( Lysis buffer)
3: Digest proteins ( with a protease) to realse the DNA
4: Precipitate the DNA ( with Alcool)
5: Determine the concentration of DNA obtained
What is the DNA fingerprinting process ?
1 : Extracting DNA 2 : Cutting and orAmplifying the DNA 3: Seperating the fragement with electrophoresis 4 : Visualizing the fragement the DNA 5 : Making a match
Why is DNA fingerpriting useful?
- Food identification
- Identifying human remains
- Proving a prisonner didnt do a crime
- Studying relateness between people
What is the job of a forensic document examiner ?
Determine the source or authenticity of a document ( a will, lottery ticket, check etc)
What are the factors that may affect handwriting ?
Position, writing instrument, time
What is a non requested samples ?Avantages and disadvantages ?
Samples written by the person that already exsist and are authenthic. Avantages : alreayx exist, cannot be altered.
What is a requested sample ?
Samples written by the person that are demanded with similar writing instrument, similar paper, words found on the document, if cursive, same thing. Advantages : Authenticity is immediate
Disadvantages : Changes in handwriting can occur due to stress, they may attempt to change their handwriting.
What is looked when comparing two document ?
- Form of the letters
- Content
- Line features
- Margins and format
What are the Methods of forgery?
freehand simulation, tracing, disguised writing
What are evidences that a document may have been forged ?
Drawing previous, forger’s tremors, speed, hesitation, unusual pen lift, patching and retouching,blunt beginning an ending
What are the most common alteration to a docuemen t?
- Erasures
- -Obliterations ( in fire)
- Alteration
- Overwritting
How to see alterations ?
Microscopes, naked eye, UV,
Oblitaration : reflecting light
UV, microsope for Aliteration
Indentation what is it and how to find it
Marks left when writting on a paper on top of it. Using ESDA, Oblique light. Go see in the notebook if you read this, page 84
Why would people analyze ink and paper
To find out if pages were added etc. They check the chemical analysis of both, and for INk, they use TLC or a microsope.
Hardware vs software ?
Hardware is components and software is programs
Hardware components ?
Cpu : processor of the computer
ROM : used to start the boot sequence and configure a computer’s components
BIOS : basic input output system
RAM : temporary info, always changing info stored on it
HDD : stores windows, programs, data files permanent record
how a comptuer works ?
Once you power up your computer a series of steps will be undertaken.
1-Power is delivered to the motherboard and all of the hardware throught the power supply
2- A power-on self-test (POST) is performed by the flash ROM
3- The flash ROM tests the motherboard to ensure that the hardware is there and follows a programmed
boot order.
4- The HDU
(usual boot device) is sent control. It locates the first sector of its disk (master boot record),
determines its layout (partition(s)), and boots an operating system.
S- You now have your desktop in front of you
6- Double click on an icon on the desktop (Excel) to open it. The CP_ locates Excel on the HDD and
loads it into RAM via the system bus and sends the output to the monitor through the video controller on
Using the keyboard, you type information which is stored into Lion
Printing the document means the data is taken from RAM, processed by the CPU, put in a printable
format and sent through the system bus to the external port where the printer is connected.
Saving the document means the data is taken from RAM, processed by the CPU, passed to the
HDD through the system bus and written to a portion of the HDD
elec devices on a crime scene :
- Each devices will be photographed
-Before the equiment is seized, they have to decided if they perform a live acquisition of the data, perform a system sthudown, pull the plug from the back of the computer
Cellphones will be turnet off and battery removed, place in a Faraday bag and turned off
ele devices at the crime lab
Devices will be examined in an isolation chamber
Devices will be switch to read only mode
Data will be extracted
Original device will go to evidence to be examined fro anything else ( fingerprints, dna etc)
-Analysis of the extracted data will begin : they look at the data, swap file data, temporary files, slack space, unallocated space, defragmenting, deleted files
Where to find evidence on the computer and online ?
Computer :the data, swap file data, temporary files, slack space, unallocated space, defragmenting, deleted files
Online : Internet cache, internet cookies, internet history, bookmark and favorite places, chat conversation, instant messags, email exchange, IP adress
