Honey Bees
Dissection
In this project we were given an animal. Shark, cat, or pig. I chose shark and had to cut it open then locate and explain different parts, external and internal. I chose to do a shark because I thought it would be the easiest to do without puking. At the beginning of the dissection, I was really squeamish and I didn't want to look at the shark, but as the project progressed I became more tolerant of the dissection.
Csi Investigation
Biology Thingymajiger 1
Name: Sean Thornton
Crime Scene: #3
Evidence being examined: Tire Track
Forensic Science used: Plaster Cast
Summary of the Science:
Plaster casts have been a way to preserve certain things that made an impression since before 1998. Impressions including a tire mark or a footprint in the dirt. Tell me some about the history of the use of impression evidence in forensics. Forensic science has existed since ancient times. Investigation Discovery Channel’s forensics timeline begins with the first recorded autopsy being performed on murder victim Julius Caesar during the 40s BCE. The timeline jumps ahead to the 1240s when possibly the first forensic science textbook was published by a Chinese judge named Song Ci entitled “Collected Cases of Injustice Rectified” (“Xi Yuan Ji Lu”). However, the first book specifically on forensic medicine may predate this – one written by Chinese physician, Hsu Chich-Ts’si during the 6th century AD. Mysteriously this text has disappeared, states Alan Gunn in his book “Essential Forensic Biology”.
As vehicles are commonly present at crime scenes, before, during or after the crime, tire impressions will often be discovered at the scene, usually left behind in soil. The enhancement and collection of these is similar to that of footwear impressions. If a tire impression is discovered at a scene the opposite impression should also be searched for, as the distance between these may provide further information on the vehicle in question. Whenever an individual takes a step, a footwear impression may potentially be left behind on the surface. Such an impression may be two-dimensional, the print left behind on a flat surface in some deposited material, or three-dimensional, formed in a soft surface such as soil. Numerous techniques are available for the enhancement and recovery of footwear impressions, though non-destructive methods should always be employed first.
In order to preserve the tire track plaster casting was used by mixing plaster of paris and water together then slathering on the track. Pry the plaster off when dry. Hopefully a tire print or footprint will show up on the bottom of the plaster slab.
Biology Thingymajiger 2
Name: Sean Thornton
Crime scene: #3
Evidence being examined: Vodka bottle
Forensic science used: Superglue fuming
Summary of the science:
Fingerprinting has solved many criminal cases, such as the case of the Night Stalker. The Night Stalker was a serial killer in Southern California who murdered 13 and assaulted many others. A teen group spotted the Night Stalker on his street and beat the crap out of him. The police stopped the group from killing 25-year old Richard Ramirez, it wasn’t until after that the police realized he was the Night Stalker. This break lead to the trial and conviction of Ramirez, who is now serving a life sentence.
Locard’s Exchange Principle states that every contact leaves a trace. What this means is that anytime someone comes into to contact with something, they take something with them and leave something behind. Often, what is left behind are fingerprints. Fingerprints are often used as a form of associative evidence, which means they can link an individual to a crime scene. There are three different types of fingerprints; visible, impression and latent. Minutia, small imperfections in a print, are unique to every individual and can therefore be linked to a specific person.
Ridge detail on nonporous surfaces, either latent or visible, can be exposed to cyanoacrylate (Superglue) fumes. These fumes will adhere to the moisture deposited by friction ridge skin and turn the ridges white. The reaction also stabilizes the ridge detail to better preserve for possible future enhancement, through use of fingerprint powder at the scene or by use of dye stains back at the Lab, and collection at a scene or in the Laboratory. You are going to see more of superglue fuming in the future because more techniques are being developed all the time to enhance it. Every few months, someone comes up with new dyes or new techniques.
Methods for Cyanoacrylate Fuming:
Name: Sean Thornton
Crime scene: #3
Evidence being examined: Blood of suspect/victim
Forensic science being used: Forensic Toxicology
Summary of the science:
There are several common substances to look for to determine whether a death is a suicide or an accident. When Marilyn Monroe was found dead from an overdose of Nembutal and chloral hydrate in 1962, a psychological analysis was done as well as a toxicological screening. These tests suggested that she fit the profile for frequent suicidal depression, even though they did not take into account the many recent positive events going on in her life at the time of her death. Very controversially, accidental death was ruled out, although the drugs used seemed obvious, since the packages were on her nightstand. While there were a number of conspiracy theories, the physical evidence suggests accidental death was the only way to explain the autopsy results. A blood sample of approximately 10 ml is usually sufficient to screen and confirm most common toxic substances. A blood sample provides the toxicologist with a profile of the substance that the subject was influenced by at the time of collection. One of the first times toxicology was used was in 1752 for an incident in England.
The testing process consists of:
Accession
Screen
Identify Presumptive Positives
Aliquot for confirmation
Extraction
Confirmation
Batch certification
Case Review by Toxicologist
Some of the advancements in the field are that scientists can tell what kind of drugs were in your system based on blood, urine, and vitreous (eyeball) fluid.
Terrance Bond died with many drugs in his system; Amphetamines, THC-COOH, Oxycodone, and Ethanol. At the time Terrance was overdosing on his Amphetamines, taking 500mL when his therapeutic range was 20-30mL. While inside the therapeutic range of oxycodone he also was very drunk. He had 3.9mL of THC and this combination definitely helped in the death of Terrance Bond.
Biology Thingymajiger 4
Name: Sean Thornton
Crime scene: #3
Evidence being examined: DNA
Forensic science being used: Nuclear DNA
Summary of the science:
Nuclear DNA is known as the molecule of life and contains the genetic instructions for the development of all living organisms, the DNA of the chromosomes found in the nucleus of a eukaryotic cell. In 1953 Francis Crick and James D. Watson described the double helix structure of nuclear DNA using data collected by Rosalind Franklin.
Extraction - First thing we did was take a strawberry and put it into a plastic bag and mashed into juice to neutralize the charge. The next thing we did was add a lysis buffer, a combination of dish soap and salt, to the strawberry juice and squeezed repeatedly thus breaking the cellular membrane of the cell to get to the DNA. Then we filtered the juice into a cup and poured it into a test tube. We added alcohol and then watched in amazement as the DNA was sucked into the ice cold alcohol, creating a DNA chain.
Amplification - PCR is typically used to amplify a specific gene, or portion of gene, so that we can study the function of that gene or gene region. Primers are used to flank the region you want to amplify. Each primer will amplify the gene sequence on both strands, creating a double-stranded gene product. The PCR process follows 3 steps:
Each step doubles the amount of DNA copies of your target sequence. You can repeat these three steps, denaturation, annealing, and elongation, 20 - 40 times to generate massive amounts of a specific genetic sequence. If you only have one copy of a gene, and you perform 40 cycles of PCR, you will have 240 copies of that gene, or 1 trillion copies.
Separation - Gel electrophoresis apparatus - An agarose gel is placed in this buffer-filled box and an electrical field is applied via the power supply to the rear. The negative terminal is at the far end, so DNA migrates toward the power source.
Analysis - No two different banding patterns are alike. Each pattern forms a DNA fingerprint which means that the print is unique and is like none other.
Name: Sean Thornton
Crime Scene: #3
Evidence being examined: Tire Track
Forensic Science used: Plaster Cast
Summary of the Science:
Plaster casts have been a way to preserve certain things that made an impression since before 1998. Impressions including a tire mark or a footprint in the dirt. Tell me some about the history of the use of impression evidence in forensics. Forensic science has existed since ancient times. Investigation Discovery Channel’s forensics timeline begins with the first recorded autopsy being performed on murder victim Julius Caesar during the 40s BCE. The timeline jumps ahead to the 1240s when possibly the first forensic science textbook was published by a Chinese judge named Song Ci entitled “Collected Cases of Injustice Rectified” (“Xi Yuan Ji Lu”). However, the first book specifically on forensic medicine may predate this – one written by Chinese physician, Hsu Chich-Ts’si during the 6th century AD. Mysteriously this text has disappeared, states Alan Gunn in his book “Essential Forensic Biology”.
As vehicles are commonly present at crime scenes, before, during or after the crime, tire impressions will often be discovered at the scene, usually left behind in soil. The enhancement and collection of these is similar to that of footwear impressions. If a tire impression is discovered at a scene the opposite impression should also be searched for, as the distance between these may provide further information on the vehicle in question. Whenever an individual takes a step, a footwear impression may potentially be left behind on the surface. Such an impression may be two-dimensional, the print left behind on a flat surface in some deposited material, or three-dimensional, formed in a soft surface such as soil. Numerous techniques are available for the enhancement and recovery of footwear impressions, though non-destructive methods should always be employed first.
In order to preserve the tire track plaster casting was used by mixing plaster of paris and water together then slathering on the track. Pry the plaster off when dry. Hopefully a tire print or footprint will show up on the bottom of the plaster slab.
Biology Thingymajiger 2
Name: Sean Thornton
Crime scene: #3
Evidence being examined: Vodka bottle
Forensic science used: Superglue fuming
Summary of the science:
Fingerprinting has solved many criminal cases, such as the case of the Night Stalker. The Night Stalker was a serial killer in Southern California who murdered 13 and assaulted many others. A teen group spotted the Night Stalker on his street and beat the crap out of him. The police stopped the group from killing 25-year old Richard Ramirez, it wasn’t until after that the police realized he was the Night Stalker. This break lead to the trial and conviction of Ramirez, who is now serving a life sentence.
Locard’s Exchange Principle states that every contact leaves a trace. What this means is that anytime someone comes into to contact with something, they take something with them and leave something behind. Often, what is left behind are fingerprints. Fingerprints are often used as a form of associative evidence, which means they can link an individual to a crime scene. There are three different types of fingerprints; visible, impression and latent. Minutia, small imperfections in a print, are unique to every individual and can therefore be linked to a specific person.
Ridge detail on nonporous surfaces, either latent or visible, can be exposed to cyanoacrylate (Superglue) fumes. These fumes will adhere to the moisture deposited by friction ridge skin and turn the ridges white. The reaction also stabilizes the ridge detail to better preserve for possible future enhancement, through use of fingerprint powder at the scene or by use of dye stains back at the Lab, and collection at a scene or in the Laboratory. You are going to see more of superglue fuming in the future because more techniques are being developed all the time to enhance it. Every few months, someone comes up with new dyes or new techniques.
Methods for Cyanoacrylate Fuming:
- Set the incubator is at 120 – 130 degrees Celsius.
- Put on your latex gloves.
- Choose the piece(s) of evidence to process.
- Place evidence in the incubator.
- Fill a petri dish with water and place it in the center of the incubator.
- Place the evidence to be processed on the right side of the incubator.
- Create a small tin foil bowl and squirt about ½ a tube of superglue into the tin foil bowl.
- Place the tin foil bowl and super glue on the left side of the incubator.
- Set a timer for 2 hours.
Name: Sean Thornton
Crime scene: #3
Evidence being examined: Blood of suspect/victim
Forensic science being used: Forensic Toxicology
Summary of the science:
There are several common substances to look for to determine whether a death is a suicide or an accident. When Marilyn Monroe was found dead from an overdose of Nembutal and chloral hydrate in 1962, a psychological analysis was done as well as a toxicological screening. These tests suggested that she fit the profile for frequent suicidal depression, even though they did not take into account the many recent positive events going on in her life at the time of her death. Very controversially, accidental death was ruled out, although the drugs used seemed obvious, since the packages were on her nightstand. While there were a number of conspiracy theories, the physical evidence suggests accidental death was the only way to explain the autopsy results. A blood sample of approximately 10 ml is usually sufficient to screen and confirm most common toxic substances. A blood sample provides the toxicologist with a profile of the substance that the subject was influenced by at the time of collection. One of the first times toxicology was used was in 1752 for an incident in England.
The testing process consists of:
Accession
Screen
Identify Presumptive Positives
Aliquot for confirmation
Extraction
Confirmation
Batch certification
Case Review by Toxicologist
Some of the advancements in the field are that scientists can tell what kind of drugs were in your system based on blood, urine, and vitreous (eyeball) fluid.
Terrance Bond died with many drugs in his system; Amphetamines, THC-COOH, Oxycodone, and Ethanol. At the time Terrance was overdosing on his Amphetamines, taking 500mL when his therapeutic range was 20-30mL. While inside the therapeutic range of oxycodone he also was very drunk. He had 3.9mL of THC and this combination definitely helped in the death of Terrance Bond.
Biology Thingymajiger 4
Name: Sean Thornton
Crime scene: #3
Evidence being examined: DNA
Forensic science being used: Nuclear DNA
Summary of the science:
Nuclear DNA is known as the molecule of life and contains the genetic instructions for the development of all living organisms, the DNA of the chromosomes found in the nucleus of a eukaryotic cell. In 1953 Francis Crick and James D. Watson described the double helix structure of nuclear DNA using data collected by Rosalind Franklin.
Extraction - First thing we did was take a strawberry and put it into a plastic bag and mashed into juice to neutralize the charge. The next thing we did was add a lysis buffer, a combination of dish soap and salt, to the strawberry juice and squeezed repeatedly thus breaking the cellular membrane of the cell to get to the DNA. Then we filtered the juice into a cup and poured it into a test tube. We added alcohol and then watched in amazement as the DNA was sucked into the ice cold alcohol, creating a DNA chain.
Amplification - PCR is typically used to amplify a specific gene, or portion of gene, so that we can study the function of that gene or gene region. Primers are used to flank the region you want to amplify. Each primer will amplify the gene sequence on both strands, creating a double-stranded gene product. The PCR process follows 3 steps:
- 95 °C Denaturation step. First, you heat the DNA to a high temperature (95 °C) so that the two strands of genomic DNA, and later PCR DNA, separate.
- Annealing Step (at ~ 50 - 60 °C). Second, you reduce the temperature so that DNA primers bind to either end of the template that you want to amplify. It is important that you have two primers, one to bind to each strand of DNA.
- Extension Step. Third, you raise the temperature to about 70 °C to activate a DNA polymerase and elongate the primer with respect to the template strand.
Each step doubles the amount of DNA copies of your target sequence. You can repeat these three steps, denaturation, annealing, and elongation, 20 - 40 times to generate massive amounts of a specific genetic sequence. If you only have one copy of a gene, and you perform 40 cycles of PCR, you will have 240 copies of that gene, or 1 trillion copies.
Separation - Gel electrophoresis apparatus - An agarose gel is placed in this buffer-filled box and an electrical field is applied via the power supply to the rear. The negative terminal is at the far end, so DNA migrates toward the power source.
Analysis - No two different banding patterns are alike. Each pattern forms a DNA fingerprint which means that the print is unique and is like none other.