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Questions and Answers
The most common type of regenerated fiber, which is derived from cellulose and is mostly plant in origin, is rayon.
The most common type of regenerated fiber, which is derived from cellulose and is mostly plant in origin, is rayon.
True
Synthetic polymer fibers, which all originate with petroleum products, are cellulose-based fibers.
Synthetic polymer fibers, which all originate with petroleum products, are cellulose-based fibers.
False
Polyester has properties similar to nylon except it is easily broken down by light and concentrated acid.
Polyester has properties similar to nylon except it is easily broken down by light and concentrated acid.
False
A disadvantage of manufactured fibers is that they can deteriorate in bright sunlight and melt at a lower temperature than natural fibers.
A disadvantage of manufactured fibers is that they can deteriorate in bright sunlight and melt at a lower temperature than natural fibers.
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Fibers are woven into textiles or fabrics.
Fibers are woven into textiles or fabrics.
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Evidence at a crime scene, like those in our recent case of the Bicycle accident, is easily identified and collected.
Evidence at a crime scene, like those in our recent case of the Bicycle accident, is easily identified and collected.
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In the case of the Missing Sister, the victim was a cashier at a bank.
In the case of the Missing Sister, the victim was a cashier at a bank.
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The murderer in the Missing Sister case was likely hiding the woman's disappearance.
The murderer in the Missing Sister case was likely hiding the woman's disappearance.
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The transfer of evidence such as a fiber from a source to a person, then to another person, is called:
The transfer of evidence such as a fiber from a source to a person, then to another person, is called:
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The cell phone of the victim was found at the scene.
The cell phone of the victim was found at the scene.
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Fibers that have been spun together are called:
Fibers that have been spun together are called:
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A small molecule that may bond to other monomers to become a polymer is called a:
A small molecule that may bond to other monomers to become a polymer is called a:
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The time from finding the body and the last time the victim was seen was 5 months.
The time from finding the body and the last time the victim was seen was 5 months.
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When fibers are transferred directly from victim to suspect or suspect to victim, this is called:
When fibers are transferred directly from victim to suspect or suspect to victim, this is called:
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Fiberglass is a fiber form of:
Fiberglass is a fiber form of:
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Half the fibers produced today are synthetic. They are categorized as:
Half the fibers produced today are synthetic. They are categorized as:
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Within 24 hours, an estimated ____ of all fibers may have fallen from a victim or been lost from a crime scene.
Within 24 hours, an estimated ____ of all fibers may have fallen from a victim or been lost from a crime scene.
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Two methods that can analyze fibers without damaging them are:
Two methods that can analyze fibers without damaging them are:
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Weave patterns have names like tabby, twill and:
Weave patterns have names like tabby, twill and:
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The number of threads that are packed together for any given amount of fabric is known as ____________________.
The number of threads that are packed together for any given amount of fabric is known as ____________________.
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Fibers are classified as either:
Fibers are classified as either:
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All plant fibers share the common polymer that is:
All plant fibers share the common polymer that is:
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One seed fiber is:
One seed fiber is:
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One stem fiber is:
One stem fiber is:
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______________ is the most common stem fiber, and is most commonly found in the textile, linen.
______________ is the most common stem fiber, and is most commonly found in the textile, linen.
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Which of the following was a faked name in the case of the Missing Sister?
Which of the following was a faked name in the case of the Missing Sister?
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Monica Miller, the driver in the Bicycle Accident case was identified because:
Monica Miller, the driver in the Bicycle Accident case was identified because:
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A forensic scientist will ask questions about:
A forensic scientist will ask questions about:
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The simplest weave pattern is the plain, or __________________, weave.
The simplest weave pattern is the plain, or __________________, weave.
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Natural plant fibers are produced from:
Natural plant fibers are produced from:
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Fiber evidence is gathered with:
Fiber evidence is gathered with:
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Natural fibers come from:
Natural fibers come from:
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The important evidence found at the bicycle accident was:
The important evidence found at the bicycle accident was:
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The most important evidence in the Missing Sister case was:
The most important evidence in the Missing Sister case was:
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The crime(s) in the Missing Sister case were:
The crime(s) in the Missing Sister case were:
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Study Notes
Fiber Types and Properties
- Rayon is the most common regenerated fiber, derived from cellulose with a plant origin.
- Synthetic polymer fibers originate solely from petroleum products.
- Polyester possesses distinct properties compared to nylon; it is less affected by light and concentrated acid.
- Manufactured fibers have a disadvantage of deteriorating in bright sunlight and melting at lower temperatures than natural fibers.
- Fibers are the fundamental components in the creation of textiles or fabrics.
Evidence Collection in Forensics
- Crime scene evidence, such as fibers, may not always be easily identified and collected.
- Early fiber collection is crucial; within 24 hours, an estimated 95% of fibers may be lost from a victim or crime scene.
- Fiber analysis can be performed using non-destructive methods like polarizing light microscopy and infrared spectroscopy.
Fiber Properties and Composition
- Fibers spun together form yarn, while small molecules that bond to form polymers are called monomers.
- Fibers are classified into natural or synthetic categories.
- Common polymers for plant fibers include cellulose, which is found in all plant-based fibers.
- Examples of seed fibers include cotton; examples of stem fibers include hemp and flax.
Case Studies Recap
- In the Missing Sister case, the murderer likely attempted to conceal the woman's disappearance.
- A fake name involved in the Missing Sister case was "Owen Bennett Jones."
- Monica Miller, involved in the Bicycle Accident case, was identified through fingerprints in AFIS.
- Key evidence from the bicycle accident included a 2010 Miata mirror and blood, while crucial evidence from the Missing Sister case comprised hair and fibers on the victim and banking records.
Weaving Techniques and Measurements
- Weaving patterns include tabby, twill, and satin.
- Thread count measures the density of threads in a given fabric area.
- The simplest weave pattern is the plain or tabby weave.
Natural Fiber Sources
- Natural plant fibers derive from seeds, leaves, fruits, and stems.
- Natural fibers can originate from plants, animals, and minerals derived from the ground.
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Description
Explore the world of fibers in textiles and their crucial role in forensic science. This quiz covers the types of fibers, their properties, and the importance of evidence collection in crime scenes. Test your knowledge on how fibers affect both fabric production and forensic investigations.
