Subjects
Maths
Chemistry
Biology
English Language
History
Responding to change (a2 only)
Infection and response
Homeostasis and response
Energy transfers (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
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Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
The cold war
Inter-war germany
Medieval period: 1066 -1509
2d religious conflict and the church in england, c1529-c1570
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
2m wars and welfare: britain in transition, 1906-1957
World war two & the holocaust
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
World war one
Britain: 1509 -1745
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Criminology
5 Dec 2025
3,139
8 pages
Princess Jayeola @princessjayeola_iwzq
Ever wondered how crime scene investigators actually process all that evidence you see on TV? From bloodstains to... Show more
Blood evidence is absolutely crucial in criminal investigations, but it's also incredibly fragile and time-sensitive. Crime scene investigators have just 48 hours to get samples to the lab before they become useless - talk about working under pressure!
The collection process depends entirely on whether the blood is wet or dried. For wet blood, CSIs soak it up with gauze pads or collect entire clothing items if possible. Dried blood gets scraped into paper packets using clean, sharp tools. Everything gets photographed first, naturally.
Once collected, each sample goes into separate evidence bags to prevent contamination, then straight into refrigerated storage. DNA profiling and blood group analysis can reveal the suspect's sex, species, and blood type - pretty impressive for a few drops of blood.
Key Point The Yorkshire Ripper case hinged on bloodstains found in Peter Sutcliffe's car that matched multiple victims - showing just how powerful blood evidence can be.
Semen stains require immediate collection using UV lights to detect them on clothing, bedding, or even victims' bodies. The "Christmas tree technique" helps scientists spot sperm cells under microscopes, which contain loads of DNA for identification.
Temperature control is absolutely critical here - samples must stay cool to avoid degradation. Each item gets sealed separately in sterile containers, then stored in databases that can instantly link crimes together.
Fingerprint collection involves photographing prints first, then using low-tack tape to lift them onto acetate sheets. Patent prints are obvious, but latent (hidden) prints need UV light, magnesium powder, or even superglue to reveal them.
Fun Fact In the Blackburn baby murder case, police collected over 40,000 fingerprints from local men - and found their match on a bottle at the crime scene.
Shoe print evidence tells investigators loads about criminals - how many there were, their entry and exit points, plus shoe type and size. CSIs photograph prints first, then build frames around outdoor impressions and pour in casting material.
These casts get digitised and shared between forces, helping track repeat offenders. The Night Stalker case cracked wide open when police discovered his rare shoe print in a garden bed - sometimes it's the unusual details that catch criminals.
Bite marks are incredibly unique evidence, especially when found on victims' skin. CSIs swab for saliva DNA, photograph everything, and sometimes take casts. Missing teeth, gaps, and crooked teeth make each bite pattern distinctive.
Gross but True The "Vampire Rapist" Wayne Borden was caught because forensic odontologists matched his teeth to bite marks left on victims' breasts.
Fibre evidence from clothing, carpets, and car seats gets carefully lifted using low-tack tape and tweezers. Natural vs synthetic fibres, plus specific dyes, can provide rock-solid links between suspects and crime scenes.
In Leanne Tiernan's murder, pink carpet fibres with a unique dye pattern on her clothes matched the killer's home - whilst fibres from her jumper were found around his nail. Cross-contamination works both ways in investigations.
Hair samples reveal loads of information - race, body location, whether it was cut or pulled out, plus DNA and blood type. Hair testing can even detect poisoning or drug use. CSIs use tweezers, clear tape, or filtered vacuum devices for collection.
Remember Casey Anthony's case focused heavily on a single hair found in her car boot that forensic experts said was consistent with a decomposing body.
Testimonial evidence comes from three main sources eyewitnesses, expert witnesses, and defendants themselves. Unlike physical evidence, these written and spoken accounts can support either the prosecution or defence case.
Police collect testimonial evidence through video recordings, audio recordings, and written transcripts at stations. Everything gets stored in secure databases and shared with the Crown Prosecution Service and defence lawyers.
The tricky bit? All testimonial evidence gets cross-examined in court, where inconsistencies and lies often surface. Expert witnesses face particularly tough questioning about their methods and conclusions.
Reality Check The Damilola Taylor case featured a fake 14-year-old eyewitness that the CPS failed to identify - showing why testimonial evidence needs careful verification.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
38
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
App Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Princess Jayeola
@princessjayeola_iwzq
Ever wondered how crime scene investigators actually process all that evidence you see on TV? From bloodstains to bite marks, every piece of physical and testimonial evidence follows strict procedures to ensure it can hold up in court and help... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Blood evidence is absolutely crucial in criminal investigations, but it's also incredibly fragile and time-sensitive. Crime scene investigators have just 48 hours to get samples to the lab before they become useless - talk about working under pressure!
The collection process depends entirely on whether the blood is wet or dried. For wet blood, CSIs soak it up with gauze pads or collect entire clothing items if possible. Dried blood gets scraped into paper packets using clean, sharp tools. Everything gets photographed first, naturally.
Once collected, each sample goes into separate evidence bags to prevent contamination, then straight into refrigerated storage. DNA profiling and blood group analysis can reveal the suspect's sex, species, and blood type - pretty impressive for a few drops of blood.
Key Point: The Yorkshire Ripper case hinged on bloodstains found in Peter Sutcliffe's car that matched multiple victims - showing just how powerful blood evidence can be.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Semen stains require immediate collection using UV lights to detect them on clothing, bedding, or even victims' bodies. The "Christmas tree technique" helps scientists spot sperm cells under microscopes, which contain loads of DNA for identification.
Temperature control is absolutely critical here - samples must stay cool to avoid degradation. Each item gets sealed separately in sterile containers, then stored in databases that can instantly link crimes together.
Fingerprint collection involves photographing prints first, then using low-tack tape to lift them onto acetate sheets. Patent prints are obvious, but latent (hidden) prints need UV light, magnesium powder, or even superglue to reveal them.
Fun Fact: In the Blackburn baby murder case, police collected over 40,000 fingerprints from local men - and found their match on a bottle at the crime scene.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Shoe print evidence tells investigators loads about criminals - how many there were, their entry and exit points, plus shoe type and size. CSIs photograph prints first, then build frames around outdoor impressions and pour in casting material.
These casts get digitised and shared between forces, helping track repeat offenders. The Night Stalker case cracked wide open when police discovered his rare shoe print in a garden bed - sometimes it's the unusual details that catch criminals.
Bite marks are incredibly unique evidence, especially when found on victims' skin. CSIs swab for saliva DNA, photograph everything, and sometimes take casts. Missing teeth, gaps, and crooked teeth make each bite pattern distinctive.
Gross but True: The "Vampire Rapist" Wayne Borden was caught because forensic odontologists matched his teeth to bite marks left on victims' breasts.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Fibre evidence from clothing, carpets, and car seats gets carefully lifted using low-tack tape and tweezers. Natural vs synthetic fibres, plus specific dyes, can provide rock-solid links between suspects and crime scenes.
In Leanne Tiernan's murder, pink carpet fibres with a unique dye pattern on her clothes matched the killer's home - whilst fibres from her jumper were found around his nail. Cross-contamination works both ways in investigations.
Hair samples reveal loads of information - race, body location, whether it was cut or pulled out, plus DNA and blood type. Hair testing can even detect poisoning or drug use. CSIs use tweezers, clear tape, or filtered vacuum devices for collection.
Remember: Casey Anthony's case focused heavily on a single hair found in her car boot that forensic experts said was consistent with a decomposing body.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Testimonial evidence comes from three main sources: eyewitnesses, expert witnesses, and defendants themselves. Unlike physical evidence, these written and spoken accounts can support either the prosecution or defence case.
Police collect testimonial evidence through video recordings, audio recordings, and written transcripts at stations. Everything gets stored in secure databases and shared with the Crown Prosecution Service and defence lawyers.
The tricky bit? All testimonial evidence gets cross-examined in court, where inconsistencies and lies often surface. Expert witnesses face particularly tough questioning about their methods and conclusions.
Reality Check: The Damilola Taylor case featured a fake 14-year-old eyewitness that the CPS failed to identify - showing why testimonial evidence needs careful verification.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
38
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
App Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
