Podcast
Questions and Answers
What is the purpose of using the precipitin test in blood analysis?
What is the purpose of using the precipitin test in blood analysis?
- To quantify the amount of blood present at a scene
- To identify the presence of human or animal blood (correct)
- To match DNA from the blood to a suspect
- To determine the blood type of a sample
What can be inferred if there is no interaction during the precipitin test?
What can be inferred if there is no interaction during the precipitin test?
- The sample is definitely human
- The sample is contaminated
- The sample is from an animal (correct)
- The test results are inconclusive
Why is understanding animal blood important in crime scene investigations?
Why is understanding animal blood important in crime scene investigations?
- To eliminate the presence of any blood at the scene
- To identify the specific animal species that may have contributed to the blood (correct)
- To find matches to human suspect DNA
- To determine the quantity of blood present from the suspect
What does the Kastle-Meyer test primarily determine?
What does the Kastle-Meyer test primarily determine?
How can blood spatter patterns assist in a criminal investigation?
How can blood spatter patterns assist in a criminal investigation?
What does the convergence point of blood droplets indicate?
What does the convergence point of blood droplets indicate?
If blood droplets emanate from a single event, what can be inferred about their trajectory?
If blood droplets emanate from a single event, what can be inferred about their trajectory?
Which test uses reduced Phenolphthalein as a reagent?
Which test uses reduced Phenolphthalein as a reagent?
What can investigators determine from analyzing blood spatter patterns?
What can investigators determine from analyzing blood spatter patterns?
How can investigators establish the distance between two walls in a blood spatter analysis?
How can investigators establish the distance between two walls in a blood spatter analysis?
What is the primary basis of the Luminol Test?
What is the primary basis of the Luminol Test?
Which of the following can lead to a false positive in the Kastle-Meyer Test?
Which of the following can lead to a false positive in the Kastle-Meyer Test?
In blood spatter analysis, what is the significance of blood droplets converging at a point?
In blood spatter analysis, what is the significance of blood droplets converging at a point?
What occurs when blood catalyzes the oxidation in the Kastle-Meyer Test?
What occurs when blood catalyzes the oxidation in the Kastle-Meyer Test?
In the Precipitin Test, what is the role of injecting human blood into a rabbit?
In the Precipitin Test, what is the role of injecting human blood into a rabbit?
What is the sensitivity of the Luminol Test in detecting blood?
What is the sensitivity of the Luminol Test in detecting blood?
Which test is no longer used due to toxicity issues?
Which test is no longer used due to toxicity issues?
What compound does blood catalyze the breakdown of in the Luminol Test?
What compound does blood catalyze the breakdown of in the Luminol Test?
What happens during the Luminol Test after blood catalyzes the reaction?
What happens during the Luminol Test after blood catalyzes the reaction?
Which option correctly describes the chemical reaction in the Kastle-Meyer Test?
Which option correctly describes the chemical reaction in the Kastle-Meyer Test?
Which component of blood is primarily responsible for oxygen transport?
Which component of blood is primarily responsible for oxygen transport?
What type of blood would contain both A and B antigens on the cell surface?
What type of blood would contain both A and B antigens on the cell surface?
In the ABO blood type system, which blood type has no A or B antigens present?
In the ABO blood type system, which blood type has no A or B antigens present?
What is the role of antibodies in blood serum?
What is the role of antibodies in blood serum?
Which of the following represents the most common blood type in Singapore?
Which of the following represents the most common blood type in Singapore?
Which type of blood cells are primarily involved in the immune response?
Which type of blood cells are primarily involved in the immune response?
How many different antigens are commonly recognized in blood typing?
How many different antigens are commonly recognized in blood typing?
What percentage of blood plasma is made up of antibodies?
What percentage of blood plasma is made up of antibodies?
What property allows conducting blood spatter analysis for event reconstruction?
What property allows conducting blood spatter analysis for event reconstruction?
What mechanism primarily aids in the removal of carbon dioxide from the blood?
What mechanism primarily aids in the removal of carbon dioxide from the blood?
What is the primary cause of arterial blood spatter?
What is the primary cause of arterial blood spatter?
Which type of blood spatter is likely to occur at high speeds?
Which type of blood spatter is likely to occur at high speeds?
What can cause multiple spatter patterns to appear close together?
What can cause multiple spatter patterns to appear close together?
What is an example of a medium velocity spatter source?
What is an example of a medium velocity spatter source?
What effect does the pressure surge from the heart have on blood spatter patterns?
What effect does the pressure surge from the heart have on blood spatter patterns?
What may happen during the transfer of blood from a hand to a wall?
What may happen during the transfer of blood from a hand to a wall?
Which condition is indicative of low velocity blood spatter?
Which condition is indicative of low velocity blood spatter?
What component contributes to the pattern created when blood dribbles down a surface?
What component contributes to the pattern created when blood dribbles down a surface?
What did Lady Lucan shout when she ran into the pub?
What did Lady Lucan shout when she ran into the pub?
What was found at the crime scene that indicated a struggle had taken place?
What was found at the crime scene that indicated a struggle had taken place?
What was Lady Lucan's blood type as indicated in the evidence?
What was Lady Lucan's blood type as indicated in the evidence?
How did Lord Lucan claim to have witnessed the incident involving Lady Lucan?
How did Lord Lucan claim to have witnessed the incident involving Lady Lucan?
What conclusion can be drawn about Lord Lucan's whereabouts after the incident?
What conclusion can be drawn about Lord Lucan's whereabouts after the incident?
What did blood spatter analysis indicate about the blood at the crime scene?
What did blood spatter analysis indicate about the blood at the crime scene?
How did the nanny's presence at the crime scene alter the police investigation?
How did the nanny's presence at the crime scene alter the police investigation?
What was the reason given for the nanny's visit to the basement?
What was the reason given for the nanny's visit to the basement?
Which principle states that no two fingers have the same prints, including identical twins?
Which principle states that no two fingers have the same prints, including identical twins?
What happens to fingerprints throughout a person's lifetime?
What happens to fingerprints throughout a person's lifetime?
What can be stated about identical twins' fingerprints?
What can be stated about identical twins' fingerprints?
What occurs if a person loses their fingerprints?
What occurs if a person loses their fingerprints?
Why are fingerprints considered more reliable than DNA for individual identification?
Why are fingerprints considered more reliable than DNA for individual identification?
Which statement is correct about the duration fingerprints last after death?
Which statement is correct about the duration fingerprints last after death?
What does the term 'friction ridges' refer to in the context of fingerprints?
What does the term 'friction ridges' refer to in the context of fingerprints?
What are the implications of removing fingerprints?
What are the implications of removing fingerprints?
Who developed a classification system that is inspired by Japanese methods?
Who developed a classification system that is inspired by Japanese methods?
What significant event in fingerprint history occurred in June 1892?
What significant event in fingerprint history occurred in June 1892?
Which of the following individuals added thumbprints to the Bertillon system?
Which of the following individuals added thumbprints to the Bertillon system?
What material did Henry Faulds find that demonstrated the potential of fingerprints for identification?
What material did Henry Faulds find that demonstrated the potential of fingerprints for identification?
What was the outcome of Edward Henry’s investigation into the murder of Walter and Ann Farrow?
What was the outcome of Edward Henry’s investigation into the murder of Walter and Ann Farrow?
Which of these authors depicted fingerprint evidence in their literary works?
Which of these authors depicted fingerprint evidence in their literary works?
What type of fingerprint is not visible to the naked eye?
What type of fingerprint is not visible to the naked eye?
What did the discovery of animal fingerprints by Locard contribute to forensics?
What did the discovery of animal fingerprints by Locard contribute to forensics?
Which chemical method reacts with amino acids during fingerprint visualization?
Which chemical method reacts with amino acids during fingerprint visualization?
In the fingerprints, what term is used to refer to the lines that help grip objects?
In the fingerprints, what term is used to refer to the lines that help grip objects?
What effect does damaging a finger have on a fingerprint?
What effect does damaging a finger have on a fingerprint?
Which of the following is a method used for dusting latent fingerprints?
Which of the following is a method used for dusting latent fingerprints?
What identity change did Marc George undergo after his surgery?
What identity change did Marc George undergo after his surgery?
What happens during fuming with cyanoacrylate in fingerprint analysis?
What happens during fuming with cyanoacrylate in fingerprint analysis?
How did the investigation in Jalpaiguri tea garden identify Kangali Charan as a suspect?
How did the investigation in Jalpaiguri tea garden identify Kangali Charan as a suspect?
Infra-red microscopy is used in fingerprint analysis primarily to determine what?
Infra-red microscopy is used in fingerprint analysis primarily to determine what?
Which fingerprint pattern describes a spiral design?
Which fingerprint pattern describes a spiral design?
What is the significance of ridge endings in fingerprint identification?
What is the significance of ridge endings in fingerprint identification?
Which option is commonly used to preserve a fingerprint after it has been lifted?
Which option is commonly used to preserve a fingerprint after it has been lifted?
In what year was Dr. Jose Covarrubias sentenced, according to the given content?
In what year was Dr. Jose Covarrubias sentenced, according to the given content?
Which of the following is NOT a component of fingerprints?
Which of the following is NOT a component of fingerprints?
Electronic databases for fingerprint matching typically provide what types of matches?
Electronic databases for fingerprint matching typically provide what types of matches?
What type of fingerprint pattern is categorized as a 'spur'?
What type of fingerprint pattern is categorized as a 'spur'?
Iodine spray is often used in fingerprint analysis to achieve what?
Iodine spray is often used in fingerprint analysis to achieve what?
What percentage of visible prints can ideally be seen with the naked eye?
What percentage of visible prints can ideally be seen with the naked eye?
Which of the following best describes the term 'bifurcation' in fingerprints?
Which of the following best describes the term 'bifurcation' in fingerprints?
What is the first principle regarding the classification of fingerprint patterns?
What is the first principle regarding the classification of fingerprint patterns?
What is the consequence of deeply damaging your finger according to the content?
What is the consequence of deeply damaging your finger according to the content?
Which procedure was used to alter Marc George's identity?
Which procedure was used to alter Marc George's identity?
Which pattern classifications are included in fingerprint analysis?
Which pattern classifications are included in fingerprint analysis?
How visible are fingerprint impressions to the naked eye?
How visible are fingerprint impressions to the naked eye?
What is the relationship between identical twins' fingerprints?
What is the relationship between identical twins' fingerprints?
What occurs when the ridges of a fingerprint sustain damage?
What occurs when the ridges of a fingerprint sustain damage?
What is mentioned as a method to 'fake' fingerprints?
What is mentioned as a method to 'fake' fingerprints?
What type of fingerprint pattern is characterized by two loops?
What type of fingerprint pattern is characterized by two loops?
What principle states that no two fingers have the same fingerprints, including identical twins?
What principle states that no two fingers have the same fingerprints, including identical twins?
Which statement about fingerprints is true?
Which statement about fingerprints is true?
What happens to fingerprints if they are damaged?
What happens to fingerprints if they are damaged?
What statistical claim is made about DNA?
What statistical claim is made about DNA?
Why can fingerprints be used as a reliable form of identification?
Why can fingerprints be used as a reliable form of identification?
What is one characteristic that differentiates fingerprints from DNA?
What is one characteristic that differentiates fingerprints from DNA?
Which of the following correctly describes the permanence of fingerprints?
Which of the following correctly describes the permanence of fingerprints?
How do fingerprints contribute to the concept of individuality?
How do fingerprints contribute to the concept of individuality?
Who was the first to introduce the use of fingerprints on contracts?
Who was the first to introduce the use of fingerprints on contracts?
What did Henry Faulds contribute to the field of fingerprinting?
What did Henry Faulds contribute to the field of fingerprinting?
Which of the following individuals attempted to set up a national fingerprint database in Argentina?
Which of the following individuals attempted to set up a national fingerprint database in Argentina?
In the case of the Stratton Brothers, how was the match to Alfred Stratton determined?
In the case of the Stratton Brothers, how was the match to Alfred Stratton determined?
What term describes the lines on fingerprints?
What term describes the lines on fingerprints?
What is the primary component responsible for the visibility of latent fingerprints?
What is the primary component responsible for the visibility of latent fingerprints?
Which literary work references fingerprints in relation to identification?
Which literary work references fingerprints in relation to identification?
Which method utilizes ninhydrin to make fingerprints visible?
Which method utilizes ninhydrin to make fingerprints visible?
What was the outcome of the fingerprint evidence found at the murder scene involving Francesca Rojas?
What was the outcome of the fingerprint evidence found at the murder scene involving Francesca Rojas?
Which significant contribution did Edward Henry make to fingerprint systems?
Which significant contribution did Edward Henry make to fingerprint systems?
What substance is used in laser fluorescence to enhance the visualisation of fingerprints?
What substance is used in laser fluorescence to enhance the visualisation of fingerprints?
What was one of the main criticisms faced by Juan Vucetich when trying to establish a fingerprint database?
What was one of the main criticisms faced by Juan Vucetich when trying to establish a fingerprint database?
Which chemical is released during fuming cyanoacrylate to visualise fingerprints?
Which chemical is released during fuming cyanoacrylate to visualise fingerprints?
How are fingerprints primarily visualized at a crime scene?
How are fingerprints primarily visualized at a crime scene?
Which principle describes the uniqueness of fingerprint patterns?
Which principle describes the uniqueness of fingerprint patterns?
What is a common use of electronic databases in relation to fingerprints?
What is a common use of electronic databases in relation to fingerprints?
Which of the following visualisation methods reacts with fats and proteins in fingerprints?
Which of the following visualisation methods reacts with fats and proteins in fingerprints?
What role does the background contrast play in fingerprint dusting?
What role does the background contrast play in fingerprint dusting?
What does infrared microscopy help to identify in a fingerprint?
What does infrared microscopy help to identify in a fingerprint?
Which component is NOT typically found in secretions that form fingerprints?
Which component is NOT typically found in secretions that form fingerprints?
Flashcards
Blood Biochemistry
Blood Biochemistry
Study of blood components and their interactions, including blood type.
Blood Type
Blood Type
Classification of blood based on the presence or absence of antigens on red blood cells.
Antigen
Antigen
Protein marker on red blood cells that determines blood type.
Antibody
Antibody
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ABO Blood Typing System
ABO Blood Typing System
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Blood Plasma
Blood Plasma
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Red Blood Cells (Erythrocytes)
Red Blood Cells (Erythrocytes)
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Hemoglobin
Hemoglobin
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Blood Serum
Blood Serum
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Blood Spatter Analysis
Blood Spatter Analysis
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Precipitin Test
Precipitin Test
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Animal Blood
Animal Blood
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Kastle-Meyer Test
Kastle-Meyer Test
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Luminol Test
Luminol Test
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Convergence Point
Convergence Point
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Trajectory
Trajectory
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How to determine the victim's position?
How to determine the victim's position?
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Blood pattern analysis & reconstruction
Blood pattern analysis & reconstruction
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Presumptive Blood Test
Presumptive Blood Test
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Benzidine Test
Benzidine Test
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Peroxidase Property (blood)
Peroxidase Property (blood)
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False Positive (blood test)
False Positive (blood test)
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Anti-sera
Anti-sera
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Chemical Basis Kastle-Meyer Test
Chemical Basis Kastle-Meyer Test
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Sensitivity (Blood test)
Sensitivity (Blood test)
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Blood Spatter
Blood Spatter
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Blood Spatter Pattern
Blood Spatter Pattern
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Low Velocity Spatter
Low Velocity Spatter
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Medium Velocity Spatter
Medium Velocity Spatter
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Cast-Off Spatter
Cast-Off Spatter
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High Velocity Spatter
High Velocity Spatter
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Transfer of Blood
Transfer of Blood
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Arterial Spurt
Arterial Spurt
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Lord Lucan's Debt
Lord Lucan's Debt
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Lady Lucan's Escape
Lady Lucan's Escape
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Nanny's Murder
Nanny's Murder
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Bloodstain Evidence
Bloodstain Evidence
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Blood Type Analysis
Blood Type Analysis
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Lord Lucan's Story
Lord Lucan's Story
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Fingerprints
Fingerprints
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Bertillon System
Bertillon System
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How did fingerprinting develop?
How did fingerprinting develop?
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Henry Faulds
Henry Faulds
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Francis Galton
Francis Galton
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Edward Henry
Edward Henry
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Vucetich's Contribution
Vucetich's Contribution
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Stratton Brothers Case
Stratton Brothers Case
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Locard's Animal Fingerprints
Locard's Animal Fingerprints
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Friction Ridges
Friction Ridges
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Fingerprint Damage
Fingerprint Damage
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Faking Fingerprints
Faking Fingerprints
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Fingerprint Patterns
Fingerprint Patterns
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Visible Fingerprints
Visible Fingerprints
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Ridge Ending
Ridge Ending
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Bifurcation
Bifurcation
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Independent Ridge
Independent Ridge
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Fingerprint Classification
Fingerprint Classification
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What are fingerprints made of?
What are fingerprints made of?
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Are fingerprints unique?
Are fingerprints unique?
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Can fingerprints change?
Can fingerprints change?
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What happens if you remove your fingerprints?
What happens if you remove your fingerprints?
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Fingerprints in forensics
Fingerprints in forensics
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What is the first principle of fingerprints?
What is the first principle of fingerprints?
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What is the second principle of fingerprints?
What is the second principle of fingerprints?
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Why are fingerprints so useful in forensic science?
Why are fingerprints so useful in forensic science?
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What are latent fingerprints?
What are latent fingerprints?
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Why are fingerprints unique?
Why are fingerprints unique?
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What is dusting powder used for?
What is dusting powder used for?
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How does ninhydrin work?
How does ninhydrin work?
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How does superglue fuming work?
How does superglue fuming work?
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What are the three main fingerprint patterns?
What are the three main fingerprint patterns?
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What is infra-red microscopy used for?
What is infra-red microscopy used for?
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What is the significance of fingerprint databases?
What is the significance of fingerprint databases?
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How are visible fingerprints different?
How are visible fingerprints different?
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What are some common fingerprint features?
What are some common fingerprint features?
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Fingerprints: A Unique Identity
Fingerprints: A Unique Identity
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Bertillon System: Early Identification
Bertillon System: Early Identification
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William Herschel: The Fingerprint Pioneer
William Herschel: The Fingerprint Pioneer
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Henry Faulds: The Fingerprint Scientist
Henry Faulds: The Fingerprint Scientist
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Francis Galton: The Fingerprint Researcher
Francis Galton: The Fingerprint Researcher
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Edward Henry: The Fingerprint Classification System
Edward Henry: The Fingerprint Classification System
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Juan Vucetich: The First Fingerprint Case
Juan Vucetich: The First Fingerprint Case
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Stratton Brothers Case: Forensics in London
Stratton Brothers Case: Forensics in London
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Locard's Animal Fingerprints: A New Discovery
Locard's Animal Fingerprints: A New Discovery
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Fingerprint Ridges: The Key to Uniqueness
Fingerprint Ridges: The Key to Uniqueness
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Fingerprint's Unique Feature
Fingerprint's Unique Feature
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Fingerprint Stability
Fingerprint Stability
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Fingerprint Regeneration
Fingerprint Regeneration
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Fingerprint's Role in Forensics
Fingerprint's Role in Forensics
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First Principle of Fingerprints
First Principle of Fingerprints
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Second Principle of Fingerprints
Second Principle of Fingerprints
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Why are fingerprints useful in forensics?
Why are fingerprints useful in forensics?
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Latent Fingerprint
Latent Fingerprint
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Fingerprint Origin
Fingerprint Origin
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Dusting Powder
Dusting Powder
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Ninhydrin
Ninhydrin
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Superglue Fuming
Superglue Fuming
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Infra-red Microscopy
Infra-red Microscopy
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Fingerprint Databases
Fingerprint Databases
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Fingerprint Features
Fingerprint Features
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Fingerprint Uniqueness
Fingerprint Uniqueness
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Study Notes
Forensic Serology: Blood
- Blood Biochemistry and Blood Type: Blood biochemistry is explained in terms of blood type.
- Blood Stain Analysis: Methods for analyzing suspected bloodstains are described.
- Blood Spatter Interpretation: Techniques for interpreting blood spatter patterns are explained.
Blood on the Suspect
- Blood Identification: Methods for determining if a substance is blood are explained.
- Human vs. Animal Blood: Tests to differentiate human and animal blood are detailed.
- Blood Source Identification: Determining whose blood is present is a key forensic objective.
- Crime Scene Reconstruction: Blood spatter patterns can help reconstruct events at the crime scene.
Blood Composition
- Blood Percentage: Blood constitutes about 8% of body weight.
- Blood Plasma: The fluid portion (55% by weight) is mostly water, proteins, waste products of metabolism, and nutrients for cells.
- Blood Cells (45% by weight): Includes various types, mainly red blood cells (erythrocytes) for oxygen transport, white blood cells (lymphocytes, phagocytes) for immune response, and platelets for blood clotting.
- Blood Serum: Serum is the liquid that separates from blood when a clot is formed.
Erythrocytes
- Size and Shape: Erythrocytes (red blood cells) are approximately 7.8 microns in diameter, with a biconcave shape and lack a nucleus.
- Principal Function: Oxygen transport via haemoglobin proteins, which bind 4 oxygen molecules per protein.
- Carbon Dioxide Transport: Carbonic anhydrase efficiently transports CO2 in the blood for removal from lungs.
Blood Typing
- Antigens: Red blood cells have surface proteins (antigens).
- Common Antigens: 30 commonly occurring antigens, with additional rarer ones.
- A-B-O System: A fundamental blood typing system.
ABO Blood Types
- Four Blood Types: A, B, AB, and O.
- Antigen Locations: A antigens are on type A cells, B antigens are on type B cells, both on type AB, and neither on type O.
- Population Distribution (Singapore): Approximate percentages for each blood type.
Blood Types and Love
- Blood Type-Based Love: The notion that blood type determines love is incorrect and disproven.
Antibodies
- Structure and Function: Antibodies (immunoglobulins) constitute about 20% of blood plasma. They bind to foreign objects (antigens) recognized as "alien".
Serum Antibodies
- Specificity: Serum contains antibodies targeted at specific surface antigens.
- Immune Response Basis: The antigen-antibody interaction underpinning the immune response.
- Antibody-Antigen Matching: Anti-A antibodies react to A antigens, and Anti-B antibodies react to B antigens.
Agglutination
- Blood Mixing: Mixing blood types A and B causes agglutination (clumping) due to Antibody-Antigen interactions.
- Blood Transfusions: Blood transfusions have strict blood type matching requirement to prevent agglutination, leading to blood clotting.
Agglutination - Specific Example
- A Blood Type Reactions: Blood cells with type A antigens do not clump or react with Anti-B antibodies.
- B Blood Type Reactions: Blood cells with type B antigens do clump or react with Anti-B antibodies.
Blood Type Distribution (Singapore)
- Rh Factors: Presence/absence of D antigen defines Rh positive (Rh+) or Rh negative (Rh-) status.
- Prevalence: Rh+ prevalence in Singapore is ~85%.
Bio-Identification
- ABO Not Unique: ABO blood type is not a unique identifier.
- More Complex Typing: Additional blood typing methods (e.g., O Rh negative typing) exist to improve identification accuracy.
- Reduced Probability: These techniques are less reliable than DNA fingerprinting and can establish innocence but not guilt.
Presumptive Tests for Blood
- Benzidine Test: A presumptive blood test (now outdated) used for identifying the presence of blood.
- Kastle-Meyer Test: A chemical test for blood, based on the peroxidase property of blood.
- Phenolphthalein: A reagent in the Kastle-Meyer test.
- Luminol Test: A sensitive test for blood using the peroxidase reaction. Used at crime scenes.
Luminol Test - Methodology
- Crime Scene Use: Used to identify possible blood traces at crime scenes.
- Sensitivity: Highly sensitive, detecting minute quantities of blood.
Chemical basis of the Kastle-Meyer Test
- Chemical Principles: The test is based on the peroxidase activity of blood to catalyze the oxidation of a chemical, causing a color change.
- False Positives: Other substances can also cause positive results for the test.
Kastle-Meyer Test Example
- Results: Shows a visible positive result indicating the presence of a blood stain.
Precipitin Test
- Rabbit-Based Antibody Production: Injecting human blood into rabbits produces anti-human antibodies (anti-sera).
- Commercial Availability: Human anti-sera are available commercially.
- Eliminating Animal Blood: Anti-sera can eliminate animal blood from an investigation.
Precipitin Reaction
- Antigen-Antibody Interaction: When anti-sera (antibodies to human blood) meets human blood components (antigens), a precipitin line forms in the medium where both are mixed.
Why do we want to know about animal blood?: Case Example
- Real World Application: Blood type and blood pattern analysis helped in an actual court case.
- Differentiation Crucial: The test established a DNA match instead of blood type.
Blood Spatter Analysis Techniques
- Is it Blood?: Presumptive tests (luminol, Kastle-Meyer) determine if a substance is blood.
- Blood Type: Blood typing gives an overview of blood types.
- Species Identification: Precipitin tests identify the species of blood.
- DNA Identification: DNA analysis identifies the person who shed the blood.
Blood Patterns in Forensics
- Blood Pattern Analysis: Examine patterns to reconstruct the sequence of events.
- Blood Velocity Impact: Analyzing patterns to determine the velocity (low, medium, or high) at which the blood hit a surface.
- Directionality: Determine the impact location and angle by examining blood spatter.
Blood Droplet Patterns: Examples
- Impact Angle Calculation: The shape of the blood impact (e.g., circular or elongated) assists in calculating impact angles at the crime scene.
- Convergence Point: Locating blood's point of origin by tracing back lines of blood droplets.
Lord Lucan Case (1974)
- Case Summary: A high-profile homicide case, where the suspect vanished.
- Crime Scene Details: Bloodstain evidence, suspect's actions, and the circumstances surrounding the event, were crucial elements of the investigation.
- Timeline: Lord Lucan's whereabouts on the night of the murder are vital for reconstructing the incident.
Her Story (Nanny)
- Timeline: The nanny's activities leading up to and following the murder are important for reconstructing the incident.
Blood and the Case of Lord Lucan
- Blood Type Evidence: Blood type analysis revealed that the victims and suspects had the following blood types.
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Description
Explore the critical aspects of forensic serology related to blood. This quiz covers blood biochemistry, stain analysis, spatter interpretation, and identification techniques crucial for crime scene investigations. Delve into the composition and significance of blood in forensic science.
