how is the knowledge of fingerprints, DNA and blood used to solve crimes?

Answer 1

Finger prints are made of grease and dried sweat. They are unique to the individual and no two persons are alike.
DNA like finger prints is unique to the individual every cell in that persons body is the same
.........Except for identical twins..........
This is evidence collected at the crime scene and must be collected in a very specific manner in order not to contaminate the evidence. This evidence is used to prove the guilt or the innocence of the accused.
It is also stored in data banks nation wide (finger prints and DNA) for possible links to other cimes

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Create a DNA Fingerprint
by Rick Groleau
http://www.pbs.org/wgbh/nova/sheppard/analyze.html

DNA. It's what makes you unique. It's the stuff that tells each and every one of your body's 10 trillion cells what it's supposed to be and what it's supposed to do. And although your DNA is different from that of every other person in the world -- unless you have an identical twin -- it's the same in every cell that makes up your body.
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But what exactly is a DNA fingerprint?
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Well, it certainly isn't an inky impression of a DNA strand. Compared to unimaginably small DNA, a fingerprint is HUGE. So what is it that we're looking at, and how is one of these fingerprints made?
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http://www.moval.edu/faculty/simmermanj/homicide/DNA%20Evidence.htm

.........What Is DNA? DNA, or ....deoxyribonucleic acid, is the fundamental building block for an individual's entire genetic makeup. It is a component of virtually every cell in the human body. Further, a person's DNA is the same in every cell. For example, the DNA in a man's blood is the same as the DNA in his skin cells, semen, and saliva. DNA is a powerful tool because each person's DNA is different from every other individual's, except for identical twins. Because of that difference, DNA collected from a crime scene can either link a suspect to the evidence or eliminate a suspect, similar to the use of fingerprints. It also can identify a victim through DNA from relatives, even when no body can be found. And when evidence from one crime scene is compared with evidence from another, those crime scenes can be linked to the same perpetrator locally, statewide, and across the Nation. Forensically valuable

Answer 2

Fingerprints and DNA (found in blood) identifies the person who committed the crime. Fingerprints and DNA are unique to that individual. Especially if the perpetrator committed a prior crime and had his/her fingerprints documented, it is an easy match to identify who committed the crime. DNA is relatively new and very expensive to analyze, but it's a 100% way to prove the identity of the criminal. No DNA (except for identical twins is the same).

Answer 3

Finger prints as with DNA, only prove the person where present or not, it will not prove the person committed the crime. for that we are back to detective work and good hard research. How many prints are on a classroom door or what DNA may be found in a hospital bin.

Prints are lass accurate though very good. DNA is you personal Bar-code and its unique to you. whether you committed the crime or where their some time before will have to be proved by your prosecution.

Answer 4

Well, everyone in the world has a reported fingerprint and blood test. sooo if someone got caught in a burglary their fingerprint would prove that they were there. Or if blood was spilled it would show whose it was.

Answer 5

when a person touches an object, he leave s his finger prints on it
there is no human in world who don`t have fingerprints
except one and this is known as dermatopothia pigmentosa reticularis(dpr)
blood has some proteins called dna which when checked by some persons body help in detecting criminal

Answer 6

there are no two exactly alike....so weeding out suspect is fool proof....