Forensics Flashcards

Question

2 Types of useful chromatography?

Answer 1

Liquid and gas

Answer 2

yes Breaking down larger compound into characteristic fragments

Answer 3

Identifying fish/meat intake from hair and finger nails So can identify geographic location

Answer 4

UV-vis spectroscopy (paint, dyes on fibres, drugs analysis) Infrared spectroscopy (looking at electric dipole moment) so looking at which bonds vibrate

Answer 5

Atomic spectroscopy

Answer 6

Griess test detected nitrite ions and nitro groups Positive identification on the hands of IRA members Was found that nitrites could be found in lots of other stuff so they were released

Answer 7

Killed by close range shot in the side of her head Found particles of gun shot residue on her head and coat Similar particles found inside right hand pocket of Barry George seen in the location of the murderer Then looked at elemental analysis 2008 was found that the evidence was not reliable

Answer 8

girls went missing Ian Huntley was caretaker at the school Attempt to burn the bodies and clothes Analysed fibres Used comparison microscope and polarising microscopy - distinguish between made made and natural fibres Showed there had been transferred of fibres between them enough for physical contact Looked at the soil and pollen from the crime scene

Answer 9

She killed her husband and boyfriend Died from flu then heart failure It was antifreeze - ethylene glycol - not got rid of by the kidney - found in blood

Answer 10

Killed waiting for the bus Blood stain found in suspects jacket

Answer 11

Stick of dynamite blew him up in his truck Atomic absorption spectroscopy grins test for nitrites Plastic fragments used to make it allows you to find the manufacture

Answer 12

Scotts test , Cobalt Thiocyanate

Answer 13

Leader of the team Principal decision maker in cases of murder, rape, abduction or other serious crime. Sufficient rank, normally detective inspector, detective superintendent, appropriately trained and experienced. Responsible for Policy File

Answer 14

Directs the forensic investigation in Complex major crimes Major Crimes where there are multiple scenes There maybe several Crime Scene Managers operating at the various scenes

Answer 15

Directs all aspects of the forensic investigation at the scene of major crimes

Answer 16

Carry out the tasks identified by the CSM at the scene of major crimes Deals with all the forensic issues, examinations and recoveries at the scenes of volume or less serious crime

Answer 17

Photography Forensic Fingerprinting

Answer 18

A missile has a kinetic energy of 1/2 mv^2 M = mass v = speed Missilesproduce a permanent cavity that equals the width of the object during its passage Shock waves (need to finish this from slide) tempory cavity?

Answer 19

Internal Ballistics What happens within the first 2 ms of the shot being fired External Ballistics Flight of the bullet or shot after leaving the barrel Terminal Ballistics Inside the target or body Dr Alisdair Dow

Answer 20

``` Lead Styphnate Barium Nitrate Antimony Trisulphide Calcium Silicide Zirconium Tetrazine ``` Primer can be shaped and located in different positions at the base of the round

Answer 21

Rifling in the barrel Imparts left or right handed spin to the bullet Up to 300 000 rpm for military assault rifles Smooth Barrel Shotgun Choke

Answer 22

Scanning Electron Microscopy Energy Dispersive X-ray Analysis (EDAX) Atomic Absorption Inductively Coupled Plasma Spectroscopy High Performance Liquid Chromatography (HPLC) Gas Chromatography Mass Spectrometry (GCMS)

Answer 23

``` Crime Scene Reagents React with the Nitrates and Nitrites in the GSR – colour change Diphenylamine (DPA) Cotton Swab, DPA and Sulphuric acid Dark Blue Griess Test Photographic paper and glacial acetic acid Orange ```

Answer 24

Known suspects for comparison or the database

Answer 25

Contain chemicals that lyse cells, denature proteins and protect nucleic acids from nucleases, oxidative, and UV damage (samples are stable for several years) Used for offender DNA databases Blood Buccal swabs Saliva

Answer 26

23 pairs (46 total) (maternal/paternal) described as homologous as they have the same size and contain the same genetic structure. Different size and shape, largest denoted 1 etc. Contain different genes When chromosomes are stained with fluorescent dyes they develop distinctive patterns of bright and dark bands

Answer 27

Also called ‘microsatellites’ Forensics uses those that are 2 to 6 bases in length Less susceptible to degradation so may be recovered after decomposition Number of repeats is highly variable among individuals (5-20% will share the STR) 100s of different STRs in the human genome

Answer 28

``` Locus = genetic location Allele = versions of the gene at the same location on the chromosome ``` Each individual will have two copies of each STR therefore increases discrimination

Answer 29

Primers for many different loci (with STR regions) can all be used in the same reaction mix, will amplify both allele 1 and 2. Primers are fluorescently labelled to aid detection. Multiple products will be generated to obtain lots of information with only one DNA template

Answer 30

Each STR product will have a specific label Different size STR products will be separated from each other by capillary electrophoresis DNA-17 STR profiling –The National DNA Database (NDNAD) of England and Wales Established on April 10th 1995 representing 9.6% of the UK population

Answer 31

2 numbers if one from your mother, one from your father One number if they are the same length 1/2 share parent and sibling half sibling 1/4 cousins 1/8

Answer 32

Single nucleotide differences can occur every 1:10,00 bp throughout the genome after the blastocyst has split in two. Hard to detect without full genome sequencing i.e. expensive.

Answer 33

Predict hair colour, eye colour, skin colour and ancestry Reduce pool of candidates

Answer 34

A multiplex genotyping assay and a prediction model based on genotype and phenotype data. Can predict blue and brown eye colour

Answer 35

22 SNP’s for hair colour prediction Four overlap with eye colour

Answer 36

Skin colour is determined by concentration of epidermal melanin and therefore number of melanocytes/melanosomes Reflectance can measure the skin pigmentation Reflectance M-index (melanin index) is normally distributed amongst the population

Answer 37

Database enables input of alleles and calculated a predicted phenotype. Certain SNPs are an absolute requirement due to their key role in determining

Answer 38

Sex: affected the masculinity/femininity of many facial segments BMI: affected large regions with underlying adipose tissues Age: affected facial structure due to degrading of skin elasticity.