Forensic Chemistry: Fingerprinting Methods

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Questions and Answers

At what point in time are fingerprints formed according to the text?

At birth

During childhood

After birth

Before birth (correct)

Which of the following statements accurately describes fingerprints?

Fingerprints change frequently throughout life

Fingerprints are not unique to individuals

Fingerprints are formed after death

Fingerprints are unique and remain unchanged (correct)

What is the primary characteristic of fingerprinting according to the text?

It is formed during childhood

It changes frequently throughout life

It is the most accurate and reliable method of identification (correct)

It is unreliable and inaccurate

When do fingerprints start to change according to the text?

Never change Signup and view all the answers

What happens to fingerprints after death based on the text?

They remain unchanged until body decomposes Signup and view all the answers

What is the color of fluorescent powders?

Red, yellow, green or orange Signup and view all the answers

Which of the following can fluorescent powders contain?

Iron particles Signup and view all the answers

What is the purpose of fluorescent powders?

The text does not provide information about the purpose of fluorescent powders Signup and view all the answers

How many different colors of fluorescent powders are mentioned in the text?

4 Signup and view all the answers

Which of the following is not a characteristic of fluorescent powders mentioned in the text?

They are used in laser printers Signup and view all the answers

What type of impressions can be made by pressing your fingers in fresh paint, wax, soap, butter, or tar?

Three-dimensional Signup and view all the answers

Which of the following materials can be used to create plastic fingerprints visible to the naked eye?

Tar Signup and view all the answers

What is the visibility of the plastic fingerprints created by pressing fingers in various materials?

Visible by naked eye Signup and view all the answers

Which of the following impressions can be made by pressing fingers in fresh paint, wax, soap, butter, or tar?

Plastic Signup and view all the answers

What distinguishes the impressions made by pressing fingers in fresh paint, wax, soap, butter, or tar?

They are permanent Signup and view all the answers

What types of fingerprints are visible to the naked eye?

Patent fingerprints Signup and view all the answers

Which of the following materials can form visible fingerprints?

Blood Signup and view all the answers

How are visible fingerprints different from latent fingerprints?

Visible fingerprints are formed by colored materials like blood or paint Signup and view all the answers

Which of the following is NOT a type of visible fingerprint?

Sweat fingerprints Signup and view all the answers

What is the main characteristic of visible fingerprints?

They are formed when fingers come into contact with colored materials Signup and view all the answers

What is a latent fingerprint?

A fingerprint that is invisible to the naked eye Signup and view all the answers

What types of surfaces can latent fingerprints be deposited on?

Smooth, rough, porous, and non-porous surfaces like metal, glass, or plastic Signup and view all the answers

What is the primary composition of a latent fingerprint?

Natural oils and sweat Signup and view all the answers

Which of the following is a characteristic of a latent fingerprint?

It is formed when the skin touches a surface Signup and view all the answers

Which of these statements about latent fingerprints is true?

They are created by the natural oils and sweat on the skin Signup and view all the answers

Study Notes

Fingerprint Formation

Fingerprints are formed during fetal development, around the 10th week of gestation.

Fingerprint Characteristics

Fingerprints are unique to each individual.
They are permanent throughout life.

Fingerprint Change

Fingerprints begin to change after death, but they remain recognizable.

Fingerprint Visibility

Visible fingerprints are impressions left on surfaces by pressing a finger.
They are visible to the naked eye.
They can be made by pressing fingers into fresh paint, wax, soap, butter, or tar.
The impressions are often distorted and can become altered.
Materials such as clay, dough, and modeling compound can also create visible fingerprints.
Visible fingerprints are distinct from latent fingerprints.

Latent Fingerprints

Latent fingerprints are invisible to the naked eye and require special techniques to be visualized.
They are composed primarily of sweat and oils from the skin's surface.
They are often deposited on surfaces, which can include glass, metal, wood, and paper.
Fingerprint powder is commonly used to visualize latent fingerprints.
The use of fluorescent powder can enhance the visibility of latent fingerprints, especially on dark surfaces.

Fluorescent Powder

Fluorescent powders are visible with ultraviolet (UV) light.
Some fluorescent powders can be viewed with a black light or a UV flashlight.
They are available in multiple colors: blue, green, orange, red, white, yellow, magenta, and pink.
They can contain chemicals such as zinc sulfide, zinc cadmium sulfide, and calcium tungstate.
They are used to visualize latent fingerprints on surfaces and create a contrasting effect.

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Description

Explore the accuracy and reliability of fingerprinting as a method of identification in forensic chemistry. Discover how fingerprints are formed before birth and remain unchanged until the decomposition of the body after death.