DNA analysis is a powerful forensic technique that helps identify... Show more
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Subjects

4
0
kfontcha10
11/19/2025
Health
1.1.6 DNA Analysis
148
•
Nov 19, 2025
•
kfontcha10
@kfontcha10_mprd
DNA analysis is a powerful forensic technique that helps identify... Show more




Ever wonder how crime scene investigators identify whose blood was at a scene? DNA analysis makes it possible! The process begins with DNA digestion, where genetic material is cut into fragments that create unique patterns for each person.
Gel electrophoresis is the key technique that separates these DNA fragments based on their size and electrical charge. Think of the gel like a molecular sieve - smaller DNA pieces travel further through the gel's porous structure than larger pieces. The gel contains agarose (a mixture of agar and buffer solution) that acts as this filter.
During the process, DNA fragments move through the gel when an electric current is applied. Since DNA has a negative charge, it naturally migrates toward the positive pole. After separation, the gel is stained with a special dye that makes the DNA visible, creating a DNA profile - a pattern as unique as a fingerprint.
Quick Tip: DNA can't be extracted from mature red blood cells (erythrocytes) because they don't contain a nucleus! Investigators must use other blood components for DNA analysis.

Setting up a gel electrophoresis is like preparing a specialized race track for DNA fragments. The process involves creating an agarose gel, placing it in an electrophoresis chamber filled with buffer solution, and carefully loading DNA samples into small wells at one end of the gel.
When analyzing results, scientists compare unknown samples against a DNA ladder (control) with fragments of known sizes. This comparison helps identify the specific restriction fragment length polymorphisms (RFLPs) - the variations in DNA fragment sizes that make each person's genetic profile unique.
Proper micropipetting skills are essential for accurate DNA analysis. This technique measures tiny liquid volumes in microliters (μl), where precision means getting the same measurement repeatedly and accuracy means getting the correct measurement. You can have precise measurements that aren't accurate (like consistently measuring 8g when something actually weighs 10g).
Remember: When loading a gel, only expel to the first stop on the micropipette to avoid introducing air bubbles into your sample wells!

Getting reliable DNA analysis results depends on your lab technique skills. The data shows that properly calibrated micropipetting should consistently measure 200 μl of water to weigh 0.2g - which is exactly what happened in 9 out of 10 trials in this experiment.
Mastering micropipetting takes practice, but it's a skill you can definitely learn. Focus on keeping your hand steady and properly managing air bubbles by using the correct two-stop pipetting technique. When you expel liquid, only go to the first stop during sample delivery to avoid pushing air into your sample.
This attention to detail in lab techniques is what makes DNA analysis so powerful in forensic science. As shown in the case study, investigators were able to determine that blood at a crime scene belonged to Anna Garcia by comparing DNA profiles - demonstrating how this technology helps solve real mysteries.
Pro Tip: In forensic work, both accuracy and precision matter! Your measurements need to be both correct (accurate) and consistent (precise) to stand up in court.
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
kfontcha10
@kfontcha10_mprd
DNA analysis is a powerful forensic technique that helps identify individuals through their unique genetic patterns. This process involves cutting, separating, and comparing DNA fragments to create distinctive profiles that work like molecular fingerprints.

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ever wonder how crime scene investigators identify whose blood was at a scene? DNA analysis makes it possible! The process begins with DNA digestion, where genetic material is cut into fragments that create unique patterns for each person.
Gel electrophoresis is the key technique that separates these DNA fragments based on their size and electrical charge. Think of the gel like a molecular sieve - smaller DNA pieces travel further through the gel's porous structure than larger pieces. The gel contains agarose (a mixture of agar and buffer solution) that acts as this filter.
During the process, DNA fragments move through the gel when an electric current is applied. Since DNA has a negative charge, it naturally migrates toward the positive pole. After separation, the gel is stained with a special dye that makes the DNA visible, creating a DNA profile - a pattern as unique as a fingerprint.
Quick Tip: DNA can't be extracted from mature red blood cells (erythrocytes) because they don't contain a nucleus! Investigators must use other blood components for DNA analysis.

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Setting up a gel electrophoresis is like preparing a specialized race track for DNA fragments. The process involves creating an agarose gel, placing it in an electrophoresis chamber filled with buffer solution, and carefully loading DNA samples into small wells at one end of the gel.
When analyzing results, scientists compare unknown samples against a DNA ladder (control) with fragments of known sizes. This comparison helps identify the specific restriction fragment length polymorphisms (RFLPs) - the variations in DNA fragment sizes that make each person's genetic profile unique.
Proper micropipetting skills are essential for accurate DNA analysis. This technique measures tiny liquid volumes in microliters (μl), where precision means getting the same measurement repeatedly and accuracy means getting the correct measurement. You can have precise measurements that aren't accurate (like consistently measuring 8g when something actually weighs 10g).
Remember: When loading a gel, only expel to the first stop on the micropipette to avoid introducing air bubbles into your sample wells!

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Getting reliable DNA analysis results depends on your lab technique skills. The data shows that properly calibrated micropipetting should consistently measure 200 μl of water to weigh 0.2g - which is exactly what happened in 9 out of 10 trials in this experiment.
Mastering micropipetting takes practice, but it's a skill you can definitely learn. Focus on keeping your hand steady and properly managing air bubbles by using the correct two-stop pipetting technique. When you expel liquid, only go to the first stop during sample delivery to avoid pushing air into your sample.
This attention to detail in lab techniques is what makes DNA analysis so powerful in forensic science. As shown in the case study, investigators were able to determine that blood at a crime scene belonged to Anna Garcia by comparing DNA profiles - demonstrating how this technology helps solve real mysteries.
Pro Tip: In forensic work, both accuracy and precision matter! Your measurements need to be both correct (accurate) and consistent (precise) to stand up in court.
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
4
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
These are notes from the genetics unit of biology
Notes about the factors of the immune system, including pathogens (treatment, the types, etc), the body's line of defenses, diseases, primary and secondary immune responses, forms of immunity, vaccine activation, and autoimmune diseases.
Honors Biology notes
generations, important terms
Different methods and how to do Divybrid Crosses.
presentation on the photosynthesis process
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user