Strawberry DNA Extraction Lab Explanation

Summary

The video, created by Danielle Parrott, introduces and guides through the process of extracting DNA from strawberries, focusing on both its purposes and the steps involved. DNA extraction is crucial for various applications such as genetic testing and forensic investigations. Danielle explains why strawberries are used for the experiment - mainly for their unique genetic makeup, which includes having eight sets of chromosomes, known as octoploid. The procedural steps are broken down, starting from breaking the cell walls to using different solutions to extract DNA, emphasizing the role of each ingredient like soap, salt, and ethanol in the extraction process.

Highlights

• The importance of DNA extraction in genetic testing and forensics 🔍
• Strawberries are octoploid, providing ample DNA for experiments 🍓
• The cell walls must be broken down to access DNA, using mashing and soap 🥤
• Salt is used to separate DNA from proteins, making it retrievable 🍚
• Ethanol helps precipitate DNA, allowing it to be collected easily 🧵

Key Takeaways

• DNA extraction has vital applications in genetics and forensics 🔬
• Strawberries are chosen due to their octoploid nature, ideal for DNA extraction 🧬
• Soap breaks down cell membranes, facilitating the release of DNA 🧼
• Salt helps detach DNA from proteins and other cellular debris 🧂
• Ethanol makes DNA visible by separating it from the solution 🍶

Overview

In the world of genetics and forensics, extracting DNA is like unlocking a treasure chest full of insights. Danielle Parrott's video walks us through this fascinating process using strawberries! Why strawberries, you ask? Because they're not just delicious but also genetically rich, carrying eight sets of chromosomes, making them perfect candidates for the task.

Danielle takes us through the meticulous yet fun process of DNA extraction. It all starts with breaking down the structural barriers of the cell using everyday items like dish soap and salt. The soap acts like a magician, dissolving oil (lipid) barriers, while the salt frees DNA by removing sticky proteins surrounding it.

The magic culminates with adding ethanol, which precipitates the DNA, making it rise like a star in the liquid solution. You can then twirl this DNA around a stick and voila, you've got a visible chunk of the building blocks of life! It's a hands-on glimpse into the fascinating world of cellular biology.

Chapters

• 00:00 - 00:30: Introduction to DNA Extraction The chapter titled 'Introduction to DNA Extraction' delves into the various purposes and procedures involved in extracting DNA from living organisms. It highlights the significance of DNA extraction in humans, noting its use in genetic testing to identify potential disorders in both infants and adults. Additionally, the chapter underscores the critical role of DNA extraction in forensic science, particularly in identifying individuals.
• 00:30 - 01:00: Applications of DNA Extraction in Forensics and Genetic Testing The chapter explores the application of DNA extraction techniques in forensics, specifically in identifying suspects through DNA collected from bodily fluids at crime scenes. It mentions the use of non-human samples, such as strawberry cells, to illustrate the DNA extraction process without ethical concerns or legal issues surrounding human DNA. Strawberries are highlighted for their unique properties, making them suitable for such educational demonstrations.
• 01:00 - 01:30: Using Strawberries for DNA Extraction The chapter titled 'Using Strawberries for DNA Extraction' explains why strawberries are suitable for DNA extraction. Strawberries have eight sets of chromosomes, referred to as 'octopod,' which provides a lot of DNA for extraction. The term 'octopod' is derived from 'octo,' meaning eight, similar to how an octagon has eight sides or an octopus has eight legs. Strawberries receive four sets of chromosomes from their maternal parent and four from their paternal parent.
• 01:30 - 02:30: Chromosome Structure and Terminology This chapter discusses chromosome structure and terminology, focusing on the concept of diploidy. Humans have two sets of chromosomes, one from each parent, making us diploid organisms. The chapter may include comparisons or examples, such as strawberries, to illustrate these concepts further.
• 02:30 - 03:00: Breaking Down Cell Barriers The chapter delves into the process of accessing DNA in strawberries by breaking down cellular barriers. It reviews basic plant cell structure, highlighting the necessity of penetrating the cell wall, which is composed of cellulose, and the cell and nuclear membranes, which are both made of lipids, to reach the DNA within.
• 03:00 - 05:00: Steps in DNA Extraction from Strawberries The chapter titled 'Steps in DNA Extraction from Strawberries' begins with the experiment of extracting DNA from strawberries. The first step discussed is placing the berry in a bag and mashing it with hands to break down the cell wall. This action marks the overcoming of the first barrier in the process. Following this, an extraction buffer, comprising water, dish soap, and salt, is added. Each of these components has a specific function, with dish soap playing a crucial role.

Strawberry DNA Extraction Lab Explanation Transcription

• 00:00 - 00:30 in this video we're going to look at both the purposes and procedures for extracting DNA from living things for humans DNA extraction is very important because when we extract DNA from human tissue we can do several things with it including genetic testing of infants and adults for potential genetic disorders I also has great use in the forensic scientist because you can identify the
• 00:30 - 01:00 remains of a dead body or you can even extract DNA from bodily fluids found at a crime scene and then in doing that discover the suspects in what happened at the crime scene itself in our activity we didn't use human cells we use the cells of strawberries now why you strawberries in this parrot and the reason we did that is because strawberries are pretty unique and that
• 01:00 - 01:30 they have eight sets of chromosomes so that's a lot of DNA now there's a super very special word for eight sets of chromosomes because that's kind of long and it's called octopod so octo means eight just like an octagon has eight sides or an octopus has eight legs and strawberries have eight sets of chromosomes right they get four from their maternal parent and four from their paternal apparently humans of
• 01:30 - 02:00 course have much less than that we only have two sets of chromosomes we get one set from our mom in her egg and one set from our dad in his sperm and there's a special name for that as well two sets of chromosomes we are called diploid sometimes pronounced diploid so dye means two octo means a and ployed let us now we're talking about sets of chromosomes so that's why we're going to use strawberries before
• 02:00 - 02:30 we can get to the DNA in strawberries we have to break down some barriers all right in some of these barriers if you remember your basic plant cell structure we're going to have to break through the cell wall made of cellulose then we're going to have to break through both the cell membrane and the nuclear membrane that are both made of lipids in order to get to the DNA inside now how are we going to do that you did it in your
• 02:30 - 03:00 experiment but we're going to look at the exact reasons for each step okay so at the very beginning right we put the berry in the bag and mashed it with our hands the goal of this was to break down that cell wall so we got through our first barrier then we added the extraction buffer right which was just water and dish soap and salt and all those ingredients have a very special purpose so the soap dish soap right it's
• 03:00 - 03:30 prides itself on cutting grease and breaking down grease well grease is a lipid just like the lipids that make up the membranes of our cells and of the nucleus so the soaps job was to break down the membranes of the cell in the nucleus next was the salt DNA in the nucleus is actually wrapped around a whole bunch of proteins but we need it to get loose from those proteins and loose from the other sill junk all
• 03:30 - 04:00 right so we can pull out just the DNA right so salt when we add that it's actually going to remove the DNA from those proteins that it's wound around and separated from other parts of the cell now after we filtered that fluid we added five milliliters of ethanol and when we added five milliliters of ethanol the DNA rose up from the strawberry solution and was suspended in
• 04:00 - 04:30 that ethanol layer and that is because so that happens because DNA is soluble in water so that's why we can't see it in the strawberry solution it's dissolved it's soluble that's dissolved in water but in ethanol its insoluble so it can't be dissolved it actually kind of pulls away and separates and is its own special thing so so that's why when we add the ethanol the DNA rises to the
• 04:30 - 05:00 top and we're able to pull it out of that strawberry solution so to put that in a diagram just to remind us we had our DNA that was dissolved in the soluble strawberry solution then we added the ethanol layer to it and the DNA rose to the top because DNA is insoluble in ethanol then
• 05:00 - 05:30 we used our stick and we wound the long DNA strands around the stick and poured it out and it was covered in DNA well then