# data[].attributes.body
DNA Extraction
I learned that the purpose of DNA extraction is for genetic testing, body identification and analysis of forensic evidence. The steps of DNA extraction, is collecting the cheek cells, bursting the cell open using a lysis solution. Next, is the separation of DNA and protein. Lastly, is isolating the DNA concentrate.

PCR
The purpose of PCR is to make more copies of DNA. The steps of PCR is, the DNA sample is contained in a PCR tube. Then primer 1 and 2, base and the nucleotides is added to the DNA sample. After adding those, the sample was brought to the DNA thermal cycler.

Gel Electrophoresis
The purpose of gel electrophoresis is to group DNA strands according to the length. This machines uses electric current to move the DNA. The shorter strands would move faster as compared to the longer strands. This enables the DNA to be grouped according to length. To observe the DNA strands, the gel would be stained with ethidium bromide. Then the gel would be placed in a UV light for observation.

# data[].attributes.body
DNA Extraction
1) DNA is isolated for 3 uses:
- Genetic Testing
- Body identification
- Analysis of forensic evidence
2) Purifying DNA from a cheek swab consists of 4 steps:
- Collection of cheek cells
- Bursting of cells to release DNA
- Separation of DNA from proteins and other debris
- Isolation of concentrated DNA
3) Addition of lysis solution is used to separate DNA from proteins and other debris

PCR
1) PCR is used to diagnose diseases, identify bacteria and viruses.
2) The DNA polymerase in our bodies will break down at temperature below 95 °C  which is necessary to separate 2 complementary strands of DNA
3) DNA polymerases will begin to add complementary nucleotides onto its strand when it locate a primer attached to a single DNA strand.

Gel Electrophoresis
1) Is used to sort DNA strands according to their lengths
2) Electric current is applied to enable movement of DNA (DNA has a negative charge)
3) Short DNA strands will move through the holes in the gel more quickly than long DNA strands.

# data[].attributes.body
[DNA Extraction]
The extraction and isolation of DNA can be used for genetic testing, body identification and analysis of forensic evidence.
There are four main steps to obtain DNA strands as it is only found within the chromosomes in a cell's nucleus. It also contains cellular proteins and debris that are unwanted.
1. Collection > 2. Use of lysis solution (detergent + proteinase K) to burst cells and release DNA > 3. Separation of DNA strands from impurities (cellular debris and proteins) with a concentrated salt solution > 4. Isolation of DNA strands with isopropyl alcohol

[PCR-Polymerase Chain Reaction]
PCR is conducted to obtain 100 billion identical copies of a specific DNA sequence within a few hours using primers, nucleotides, DNA polymerase and 3 temperatures.
At 95°C, the double helix structure of DNA separates into 2 single strands.
At 50°C, primers will attach and lock onto target sites of the DNA before allowing the strands to rejoin.
At 72°C, nucleotides will be attached onto the primers, corresponding to the sequence of the DNA with the help of DNA polymerase before detaching to become desired fragments.
This process of heating and cooling will then be repeated to obtain identical copies.

[Gel Electrophoresis]
It is used to sort and separate DNA strands according to their length.
Dyed DNA strands will be added into wells of a gel before applying electrical currents.
The shorter the stands (higher bp), the further and faster they will move through the holes in the gel while the longer strands (lower bp) will be located closer to the starting point.
The gel will then be stained and observed against a DNA size sample in terms of bp, base pairs.

# data[].attributes.body
DNA Extraction
The isolation of DNA is used for:
- Genetic Testing
- Body Identification
- Analysis of forensic evidence
There are 4 steps to follow in order to purify DNA from a cheek swab:
1. Collect cheek cells
2. Burst cells open to release DNA by adding lysis solution, which contains detergent and an enzyme called proteinase K. Detergent causes the cells to burst open and releases their DNA, while the proteinase K cuts the histones, which is wrapped around by the DNA.
3. Separate DNA from proteins and debris by adding concentrated salt solution. The salt causes proteins and other cellular debris to clump together.
4. Isolate concentrated DNA by adding isopropyl alcohol. DNA is insoluble in isopropyl alcohol, hence it comes out of the solution.

PCR
- The purpose of PCR is to make more DNA copies to diagnose diseases, identify bacteria and viruses, match criminals  to crime scenes, etc.
- Firstly, primers are added to the PCR tube as they are powerful tools for copying very specific DNA sequences.
- Secondly, nucleotides are then added as they are the A's, C's, G's and T's that make up the DNA code.
- Lastly, DNA Polymerase is added to the PCR tube. DNA Polymerase molecules read the DNA code and then attach matching nucleotides to create DNA duplicates.
- Once the PCR tube is filled with all of the reaction components, it is placed into a DNA Thermal Cycler. It is able to heat precisely and cool the tube at specific times during the next hour. Changes in temperature are important in making the reaction work.

Gel Electrophoresis
- It is used to sort DNA strands according to length. This method is also used for separating other types of molecules, like proteins.
- The "gel" acts like a filter that sorts the DNA strands.
- "Electrophoresis" refers to how the DNA strands are pushed through the gel filter by adding an electrical current.
- DNA strands of the same length will then end up in a group.
- The sorted groups of DNA are then visible to the naked eye by staining them. These groups show up as bands in the gel.

# data[].attributes.body
DNA Extraction
DNA is isolated for many reasons, some of which is genetic testing, body identification and analysis of forensic evidence. DNA is inside almost every cell in our body. There are 4 steps to extract DNA from a cell.
1) Collect cheek cells
- bucca swap was used to extract the cheek cells
2) Burst cells open to
release DNA
- Lysis solution contain detergent and proteinase K.Detergent
3) Separate DNA from proteins and debris
4) isolate concentrated DNA

PCR
1) PCR are use to focus in on a segment of DNA and copy it billions of times over and used to diagnose diseases, identify bacteria and viruses.
2) The primer are design to attach to sites of DNA strand that are at either end of the DNA strand.
3)  DNA Polymerase are able to copy a cell's DNA. It attaches itself near the end of the primer and starts adding nucleotides.
4) The DNA double helix break up at 95 degree celcius. when cooled down to 50 degree celcius  , the primers will lock onto the selected strands. DNA polymerase was activated at 72 degree celcius, the nucleotides will be attacted to the primers . The cycle is repeated to obtain the identical DNA strand.

Gel Electrophresis
- Its a technique that used to sort and separate DNA strands that cannot been seen by naked eye according to their length.
Electrical current was apply to the gel to make the DNA strand to move.
Shorter DNA strand will move further while longer strands will move slower down the gel.
A dye will be used to stain the gel and observed the travel distance of DNA strand.

# data[].attributes.body
DNA Extraction
DNA are extracted and isolated for various reasons such as: genetic testing , body identification, analysis of forensic evidence. DNA extraction is crucial part of the whole process because DNA needs to be purified from other proteins and cellular contaminants such as histamine.  Lysis sloution consists of detergent which disrupt the cell membrane and cause the cheek to burst open and release the DNA found in it.
PCR
The purpose of PCR is making more copies of DNA to identify bacteria and viruses therefore diagnose disease. Firstly primers are added to the PCR tube to make copies of the DNA sequence. Nucleotides are then added to make the DNA codes base on the sequence. Lastly, DNA polymerase is added to the tube read the DNA code and makes more copies of which.

Gel Electrophoresis
This test sorts the DNA strand according to the length with the longest nearest to the starting point and shortest furthest from the starting point. This is beacause shorter Dna strands tends to move faster than longer strands hence shorter strands are found further from the starting point. These DNA strands moves by the electric current applied.

# data[].attributes.body
DNA is being isolated for many reasons, some of which is genetic testing, body identification and analysis of forensic evidence. DNA is located in the every cell of our body. When cells are being placed in lysis solution, the ingredients in it would disrupt the cell membrane and nuclear envelope, causing the cells to burst open and release their DNA. As the DNA is still wrapped tightly around the histones, the enzyme cuts apart the histones to free the DNA. When salt is added, it causes proteins and other cellular debris to clump together. When the tubes were being placed in the centrifuge, the motion induced caused clumps of proteins and cellular debris to collate at the bottom, while the DNA is contained within the remaining liquid. Isopropanol alcohol was added to the extracted DNA solution as DNA is insoluble in isopropyl alcohol which causes clumping when mixed. After another round of placing the tube into the centrifuge, the DNA is collected at the bottom of the tube. This is when the DNA is being isolated.

PCR can generate numerous identical copies of DNA sequence. PCR needs DNA that has been extracted from cells as the main purpose is to generate more DNA copies. DNA double helix separates at high temperature which creates 2 single stranded DNA molecules which will attempt to pair up but the primers added will attach to sites on the ends of the DNA strands that makes the copy. Nucleotides are the A’s, C’s, G’s and T’s that make up the DNA code. DNA polymerase molecules read the DNA code and then match identical nucleotides to create the DNA copy.

Gel electrophoresis is used to sort and measure DNA strands that are not visible. It is usually used when DNA strands are needed to be sorted according to length. Electric current is added to make the DNA move from one end of the gel to the other. DNA strands of the same length would move at the same speed together. Staining allows the DNA to be visible. To carry this out, first the gel has to be made, the gel apparatus has to be set up, the DNA has to be loaded onto the gel, and the electrical current has to run through the gel and lastly, staining the gel and analyzing the results.

# data[].attributes.body
1) DNA is isolated for genetic testing,body identification and analysis of forensic evidence.
The steps are collect cells,burst cells to release DNA, separate DNA from proteins and debris and lastly isolate concentrated DNA
2) Polymerase chain reaction is used to diagnose diseases, identify bacteria and viruses. It can generate 100 billion identical copies of specific DNA sequence in a short time. It only requires a test tube reagents and heat. The purpose is to replicate more DNA. After thirty cycles, over billion fragments that contain target sequence and only sixty copies of longer molecules
3) Gel Electrophoresis can be used to sort DNA according to length. It is useful with separation of different molecules.
Shorter strands move faster and further away from starting point as compared to longer strand. Those with same length will travel and group  together.

# data[].attributes.body
1) DNA Extraction
- There are 3 uses for DNA Extraction:
> Genetic Testing
> Body Identification
> Analysis of forensic evidence
- Usually cheek cells are taken for DNA extraction as the cells are loose.
- There are 4 steps to DNA Extraction.
a) Collecting cheek cells
- Cell are collected onto a swab and placed into a solvent.
b) Bursting of cells open to release DNA.
- Lysis solution is added into the tube contain a solvent and the swab.
- Lysis solution contains detergent and an enzyme called proteinase K
- The detergent disrupts the cell membrane and the nuclear envelop, causing the cell to burst open and releasing the DNA.
Proteinase K cuts apart the histones that are wrapped tightly around the DNA.
- This will then free the DNA
c) Separating the DNA from proteins and debris
- Concentrated salt solution is added.
- It causes the protein and other cellular debris to clump together.
- This leaves the DNA free in the solution while the proteins and other cellular debris that has clumped together will sink to the bottom of the tube when placed in the micro-centrifuge.
d) Isolating concentrated DNA
- Isopropyl alcohol is added into a tube containing DNA in the solvent only.
- By mixing the tube, as DNA is not soluble in isopropyl alcohol, it comes out of the original solution and clumps together, so the DNA can be seen with the naked eye.

2) PCR
- Polymerase Chain Reaction
- can generate 100 billion identical copies of a specific DNA sequence
- requires a test tube, a few simple reagent and a source of heat
- Start by placing extracted DNA into specially designed PCR tubes for the temperature difference while multiplying
There are 4 reaction components that will be added into the solvent.
a) Primer 1:
- attach to the sides on the DNA strands that are at either ends of the segment you want to copy
-powerful tools used for copying very specific DNA sequences since there is almost no chance that they will target the wrong sites.
b) Primer 2:
- attached to the second site
- similar to Primer 1 but on the opposite end
c) Nucleotide:
- are the A's, C's, G's and T's
- makes up DNA code to create billions of DNA copies
d) Polymerase
- act like tiny machines that read the DNA code and attach matching nucleotide to create DNA copies
- specially selected to withstand high heat

- after putting all the reaction components into the tube, which will be placed into the DNA Thermal Cycler.
- it helps to change temperature according to what is needed to multiply quicker.

3) Gel Electrophoresis
- Scientist use for sorting DNA strands according to length.
- Also used for separating other types of molecules, like proteins.
There are 5 steps to carry out:
a) Making the gel
- The gel used acts as a filter that sort the DNA Strands, its like a sponge made of Jell-O with many small holes in it.
b) Set up the gel apparatus
- A comb is added to the gel when set to cool, this is to insert the DNA sample into the gel.
c) Load the DNA sample into the gel
- DNA samples are placed into one of the holes using a micropipettor.
- The samples are stained with loading buffer so that it will be easier to see, it also makes the sample thicker so that is drops into the holes instead of floating away.
- There are also DNA size standard which will be placed beside the DNA sample
- the DNA size standard contains DNA strands of known length, running it beside your sample will provide a reference as to what length are your DNA strands in your sample
d)Hook u the electrical current and run the gel
- this is the electrophoresis part of the test.
- by adding the electrical currents, the DNA strands are forced to move from the holes to the other end of the gel
-short strand move through the holes in the gels more quickly than the longer strands.
- over time, the shorter strands in the sample will move further away from the starting point than the longer strands.
DNA strands of the same length will move at the same speed and end up grouped together
e) Stain the gel and analyse the results
- Ethidium Bromide is added and it binds to the DNA and shows up under fluorescent light

# data[].attributes.body
DNA Extraction:
- It is done for:

Genetic Testing

Body Identification

Analysis of Forensic Evidence

- The lysis solution contains detergent and enzyme proteinase K. The detergent disrupts the cell membrane and nuclear envelope, causing the cells to burst open and release their DNA. The DNA that is wrapped very tightly around histones(proteins) are freed as the proteinase K cuts apart the histones to free the DNA.
- After the step of adding salt solution to allow proteins and other cellular debris to clump together, Isopropyl alcohol is added to the new tube and inverted for several times. DNA is not soluble and does not stay dissolved in Isopropyl alcohol. Therefore, it comes out of the solution and we can now see clumped DNA with our naked eye.

PCR:
- PCR is used every day to diagnose diseases, identify bacteria and viruses, match criminals to crime scenes, and in many other ways.
- When Primer 1 and Primer 2 are added to the PCR tube, they will attach to sites on the DNA strands that are at either end of the segment we want to copy.
- Nucleotides are the ‘A’s, ‘C’s, ‘G’s and ‘T’s that make up the DNA code. These genetic building blocks will be used to create billions of DNA copies.

Gel Electrophoresis:

- Used to sort and determine the different sizes of DNA strands that cannot be seen or measured using a normal ruler.
- The gel acts as a filter to sort the DNA strands.
- Electrophoresis is when electric current is used to move the DNA strands along the gel. The shorter strands move faster than the longer strands of DNA.

# data[].attributes.body
DNA extraction

DNA needs to be purified away from proteins & other contaminants. Step to purify DNA,

1.Collect cells from the sample.

2.Burst cells open to release DNA by adding lysis solution and place in water bath. Lysis solution contains detergent and enzyme Proteinase K.

3.Separate DNA from the proteins and debris by adding concentrated salt solution which causes proteins and cellular debris to clump together followed by centrifuging.

4.Isolate concentrated DNA by adding isopropyl alcohol and place in centrifuge allowing the DNA to sink.

PCR

Important components added are Primers, DNA polymerase and Nucleotides.

1.Primers are short pieces of DNA which are designed to copy very specific DNA sequence.2 primers are used in PCR, one attaches to the top strand at one end of the desired segment and the other attaches to the bottom strand at the other end.

2.DNA polymerase molecules read the DNA code and then attach matching nucleotides to create the DNA copies.

3.Nucleotides are genetic building blocks which are used to create the DNA copies.

Gel Electrophoresis

Allows to determine the lengths of DNA strands. Gel is used as a filter that sorts DNA strands while electrophoresis is the process of pushing DNA stands through the gel filter by using electrical current. The DNA strands in the sample will then sort themselves. Afterwards, staining the sorted groups of DNA makes it visible to naked eye.

# data[].attributes.body
1) DNA extraction
We can extract DNA cells from our cheeks. Lysis solution is used to burst cells open to release DNA
Concentrated salt solution is used to separate DNA from protein and debris. DNA is insoluble in Isopropyl acohol and causes it to clump together hence it is used to isolate concentrated DNA.

2) PCR
PCR is used to generate  many identical copies of DNA sequence. There are a few components added to DNA extract; Primers, Nucleotides, DNA polymerase.

3) Electrophoresis
It separates charged molecules according to size. DNA is sorted when it moves from negatively charged to positively charged.

# data[].attributes.body
1. DNA extraction
DNA extraction is used for body identification,  genetic testing, and forensic investigation.
there are 4 steps to when it comes to purifying DNA. First, cheek cells are collected by swabbing a buccal swab over the internal part of the mouth. Then, lysis solution is added to release DNA in the cells by bursting the cells. Concentrated salt solution is then added to separate DNA from protein and debris. Lastly, isopropyl alcohol is added to the DNA and centrifuged to allow the DNA to sink.

2. PCR
PCR is used to copy fragments of DNA and produce many identical copies. Primers are attached to the part where copying is needed.

3. Electrophoresis
Electrophoresis is a method used to sort DNA strands according to their length. The gel acts as a filter used to sort the DNA strands.

# data[].attributes.body
1. DNA Extraction
There are 4 steps when purifying DNA. The first step is to collect cheek cells by using buccal swab and swab over the inside of the mouth and placed it into a Eppendorf tube. Some lysis solution which contains 2 important ingredients will be added into the tube. The 2 important ingredients are detergent and proteinase K. Secondly, the cells burst open to release DNA with the help of the proteinase K as it cuts apart the histones. Thirdly, the DNA is separated from proteins and cellular debris as when concentrated salt solution is added, the salt causes proteins and other debris to clump together. Lastly, concentrated DNA is isolated by adding isopropyl alcohol into the DNA solution and invert it a few times. Clumped DNA can be seen with naked eye since it comes out of the solution as it is insoluble in isopropyl alcohol.

2. PCR
The purpose of Polymerase Chain Reaction (PCR) is to make more DNA copies. PCR tubes are designed for even heat distribution since PCR works by heating and cooling the solution repeatedly. Firstly, extracted DNA is moved into a special PCR tube. Primer 1 is added next which will attach to sites on the DNA strands that are at end of the segment you want to copy. They are powerful tools for copying specific DNA sequences as there is almost no chance that they will target the wrong sites. This is followed by Primer 2 which will attach to the second site. Nucleotides is then added to the PCR tube. These genetic building blocks will be used to create billions of DNA copies. Lastly, DNA polymerase will be added and the molecules act like tiny machines that read the DNA code & then attach matching nucleotides to create DNA copies.

3. Gel Electrophoresis
Gel electrophoresis is used to sort DNA strands according to length and this is also useful for separating other types of molecules such as proteins. The “gel” is the filter that sorts the DNA strands while “electrophoresis” is how we push the DNA strands through the gel filter. Short strands move through the gel faster than long strands.

# data[].attributes.body
DNA extraction has 4 major steps involved:
1. Collect cheek cells by swabbing the internal part of the mouth
2. Burst cells open to release DNA using a lysis solution as it contains a detergent that will distrust cell membrane and nuclear envelope then cause the cells to open. Lysis solution also contains proteinase K which cuts apart the histones in order to free DNA
3.Separate DNA from proteins and debris using a centrifuge
4. Isolate concentrated DNA using isopropyl alcohol then followed by centrifuge.

PCR also known as Polymerase Chain Reaction has 3 major steps:
1. Denaturation of template into single strand
2. Annealing of primer to each original strand for new strand to synthesise
3. Extension of new DNA strands from primer

Gel electrophoresis was used when scientist want to sort DNA strands according to length. We use "gel" to sort the DNA strands by placing DNA samples at one end of the gel and use electrical current to push the DNA strands through the "gel". Short strands will move faster through the "gel" than long strands, this how they are separated. Afterwards, staining is done to make the DNA strands visible by naked eye.

# data[].attributes.body
Tay Shi MIn FS1701

1. DNA extraction
DNA are extracted and isolated for various reasons such as: genetic testing , body identification, analysis of forensic evidence.
DNA extraction is crucial part of the whole process because DNA needs to be purified from other proteins and cellular contaminants such as histamine. However a cell is needed for all this process to occur as DNA is found in chromosomes which is found in the nucleus and the nucleus is found in the cell. Thus the cell is needed for all this process to occur.
in the case a cheek cell is used to obtain the DNA found in it.
After obtaining the cheek cell using a buccal swap, lysis solutiom is added to the tube.
Lysis sloution consists of detergent which disrupt the cell membrance and cause the cekk to burst open and release the DNA found in it. Proteinase K on the other hand cuts apart the histones to free the DNA

# data[].attributes.body
1. DNA extraction

# data[].attributes.body
1. DNA extraction
The first step to purify DNA is to collect sample cells. The next step is to burst open cells to release DNA by adding lysis solution, which contains detergent and proteinase K to help to free the DNA from the cell. DNA is then separated from proteins and debris by adding concentrated salt solution to clump proteins and debris together. The mixture is then centrifuged so these proteins and debris sink to the bottom of the tube and liquid with DNA can be extracted. Concentrated DNA is then isolated by adding isopropyl alcohol to clump strands of DNA together and make them visible as DNA is insoluble in this solvent.

2. PCR
Samples are added with primer 1, primer 2, nucleotides and DNA polymerase. Primer 1 attaches to one side of the DNA strand that is on one end of the segment of interest while primer 2 attaches to the other side. Nucleotides are the genetic building blocks of DNA. DNA polymerase attaches matching nucleotides to create DNA copies.

3. Gel electrophoresis
DNA strands can be separated by gel electrophoresis into short, medium or long strands. By passing an electric current through the gel, negatively charged DNA moves along the electric current to the positive charged area of the gel. Short DNA strands can move through the gel faster than long DNA strands. At the end of the electrophoresis, large groups of DNA strands are sorted by length, appearing as bands on the gel, which can be compared with the DNA size standard to estimate its length in number of base pairs.

# data[].attributes.body
(i) DNA extraction:

The lysis solution consists of detergent and an enzyme called proteinase K. The detergent disrupts the cell membrane and nuclear envelope, causing the cells to burst open and release DNA. As DNA is still wrapped around histones, proteinase K cuts the histones and release the DNA. Concentrated salt solution causes the proteins and other cellular debris to clump together so it is easier to isolate the DNA via centrifugation.

(ii) PCR:

The thermal cycler heats up to 95 degree celsius where the DNA double helix separates, creating two single-stranded DNA molecules. The temperature lowers to 50 degree celsius so that the primers can lock onto their target before the DNA single strands rejoin. It will then increase slightly to 72 degree celsius where DNA polymerase is stimulated to copy the strand.

(iii) Gel electrophoresis:

The DNA strands are pushed through the gel filter by electrical currents. Shorter strands move through the holes in the gel more quickly than longer strands. Thus, shorter strands in the sample will move further away from the starting point. DNA of the same length will move at same speed and group together.

# data[].attributes.body
1)     DNA Extraction

Can be used for genetic testing, body identification and analysis of forensic evidence.

Lysis solution is used to release DNA from cells. It contains detergent which can disrupt the cell membrane and proteinase K which can separate DNA from histones.

Salt solution is used to clump protein and debris that will be remained in the bottom of the tube after centrifuged.

As DNA is not soluble in isopropyl alcohol, we can use isopropyl alcohol to separate DNA from liquid.

2)     PCR

Polymerase chain reaction is used to copy desirable fragment of DNA strand.

30 cycles can create a billion of fragments.

3)     Gel electrophoresis

Used to sort and measure DNA strands

Also can be used for protein.

Electrical current is used in the test due to the presence of buffer liquid which is a salt water that can allow electrical charges flow through the gel.

Ethidium bromide is used for staining.

# data[].attributes.body
1. DNA Extraction

After the collection of the cells, lysis solution is added and is placed in a warm water bath. The lysis solution contains detergent which disrupts the cell membrane and nuclear envelop, causing the cell to burst, releasing the DNA. It also contains proteinase K, which cuts apart the histones to free the DNA. Concentrated salt solution is then added, which causes the proteins and other cellular debris to clump together. It is then placed in a centrifuge to allow the clump to sink to the bottom. The DNA solution is separated from the debris and isopropyl alcohol is added. As DNA is not soluble in isopropyl alcohol, it will clump up and come out of the solution. It is then placed in a centrifuge to allow the DNA clump to sink to the bottom. After removing the liquid and drying the DNA, the extraction is complete.

2. PCR
PCR is used to create billions of copies of a specific DNA sequence. After adding the extracted DNA to the PCR tube, primers are added. Primers attach to either end of the DNA segment that is to be copied. Nucleotides added is used to make the DNA copies. DNA polymerase added reads the DNA code and creates the copies by attaching matching nucleotides. The tube is then placed into a DNA Thermal Cycler, which can precisely heat and cool the tube, which is important for making the reaction work. At a high temperature, the DNA separates. When it is cooled, the primers lock onto its target before the DNA strands can pair up. At another temperature, the DNA polymerase activates, locates the primer, and starts to make the DNA strand. It is repeated for another 2 cycles, after which the desired fragments can be obtained.

3. Gel Electrophoresis
It is a way to sort and measure DNA strands. The gel is the filter that sorts the DNA strands. An electric current is added, which makes the DNA move. This is ‘electrophoresis’, which is how the DNA strands are pushed through the gel filter. The shorter strands move through more quickly compared to the longer strands. The DNA strands sort themselves and when stained, can be seen as bands in the gel. The gel block is then stained with ethidium bromide, which binds to DNA and shows up under fluorescent light. It is then placed on a UV light box, where it is  compared with the standard and estimates are made. The estimated length is in base pairs.

# data[].attributes.body
(1) DNA Extraction
In the extraction of DNA 3 solutions are needed, without those 3 important solutions the extraction of DNA will not be possible.
The first solution that is added was the lysis solution, which contains detergent and proteinase K. The detergent disrupts the cell membrane and nuclear envelope, causing the cells to burst open and release their DNA. The proteinase K cuts apart the histones to free the DNA.
The second solution added was salt solution, which causes proteins and other cellular debris to clump together.
The third solution added was isopropyl alcohol, which causes the DNA to clump together as they are insoluble in isopropyl alcohol thus driving the DNA out of the solution.

(2) PCR
PCR is a simple process that requires a special PCR tube, 3 simple reagents and a heat source.
The first reagent added is Primer 1 which will attach to sites on the DNA strands that are at either end of the segment that is needed to be copied.
The second reagent added is nucleotides, which will be used to create billions of DNA copies.
The third reagent added is DNA Polymerase, which act like tiny machines that read the DNA code and then attach matching nucleotides to create DNA copies. The type of DNA Polymerase used must be able to withstand the high heat of the PCR reaction since the solution will be heated and cooled multiple times.

(3)  Gel Electrophoresis
A method to sort DNA strands according to the length.
The gel, which can be made from scratch with just 2 ingredients and 4 equipments, contains many small holes in it and acts as a filter which sorts the DNA strands. DNA samples are then placed into holes created using a gel comb at one end of the gel. Since DNA has a negative charge, adding an electrical current will make the DNA move through the small holes of the gel. The shorter strand DNA will move through the holes in the gel more quickly compared to the longer DNA strands. Over time the short DNA strands will travel further away from the holes created using the gel comb. DNA strands of the same length will travel at the same speed and be grouped together thus the DNA strands sort themselves.
To be able to see the DNA, they first need to be stained using DNA staining solution. Afterwards the gel is placed over a UV light machine.

# data[].attributes.body
(i) DNA extraction
The purpose of having DNA extraction is that we are able to have  genetic testing, body identification and analysis of forensic evidence. Secondly, we are able to extract out cells easily for DNA extraction . Thirdly, we are able to obtain the DNA through a few of the tests that break apart the cell one by one

(ii) PCR
DNA polymerase molecules act like tiny machines that read the DNA code and then attach matching nucleotides to create DNA copies. Our DNA strands is able to withstand high temperature without damaging itself apart from opening the strands.Primers are also necessary because DNA polymerase can't attach at just any old place and start copying away. It can only add onto an existing piece of DNA.

(iii)Gel electrophoresis
Gel electrophoresis is able to filter the DNA strands which sort the DNA strands out. By using electrical current ,we are able to move the DNA to be filter as it moves. The DNA strands are sorted and grouped by the positive and negative charge of the current

# data[].attributes.body
(i) DNA extraction:

To obtain isolated DNA samples, the crucial step is DNA extraction. Firstly, consists of collecting cheek cells by swabbing cheek with a buccal swab. Secondly, bursting cheek cells open to release the DNA by the addition of lysis solution. Thirdly, separating the DNA from proteins and cellular debris by placing solution in a warm water bath followed by addition of concentrated salt solution and then placed into a centrifuge. Lastly, isolating concentrated DNA by adding isopropyl alcohol and placing it into the centrifuge, then dry the DNA to finally obtain a DNA sample.

(ii) PCR:

PCR generates more identical DNA copies of a specific DNA sequence by utilising DNA that has already been extracted from cells. During the third cycle, desired products will start to appear. Two strands will appear that begins with primer one and ends with primer two. These are just partial segments of the targeted DNA. As the cycle continues, these desired products will then become the majority and at the end of thirty cycles, produces over a billion fragments containing only the target sequence and only sixty copies of the longer molecules. Hence, will have an almost pure target sequence.

(iii) Gel electrophoresis:

Gel electrophoresis helps to measure the length of DNA strands and to do so, involves an electrical field. Electrophoresis is to push DNA strands through the gel filter and add electrical current to move the DNA, sorting out strands that are long and short or of the same length. When electrical current is turned on, the DNA will move to the positive end through repulsion of the negative charge.

# data[].attributes.body
1) DNA Extraction

Our body cells contains nucleus, which in turn contains DNA strands. Lysis solution is added into the cheek sample which is made up of detergent and an enzyme known as Proteinase K. Lysis solutions aids in causing the proteins that are surrounding the DNA to be opened, so that the DNA can be isolated and extracted. In order for the lysis solution to work on the cell, it has to be placed in a warm water bath. After being placed in the warm water bath, it undergoes a centrifuge which spins the tube at high speeds in order to break apart the protein clumps and cellular debris which comes about from the DNA strands. As the DNA is too small for even the naked eye to see, isopropyl alcohol has to be added in order to see the DNA.

2) PCR

The main aim of PCR method is to make copies of DNA. If you want to copy a particular segment of DNA, you can attach the primers to that particular segment that you want to copy. The genetic code are made up of nucleotides. Polymerase has to be added in order to be able to interpret the DNA codes and match them to the correct nucleotides.

For the reaction to occur successfully, the tube has to be placed in a thermal cycler for the heating and cooling processes to happen at a certain temperature. As heating occurs, the double-helix structure of the DNA is broken into 2 single strands. The primers lock the nucleotides so that the double-helix can be reformed.

3) Gel electrophoresis

Gel Electrophoresis is one method that can be used in differentiating the different lengths of DNA strands. The gel acts as the filter responsible for sorting out the different DNA strands, as it has small pores.

# data[].attributes.body
1. DNA Extraction

DNA is contained in the nucleus of body cell.
Lysis solution contains detergent and enzyme called proteinase K. This solution is added to it to burst the cell open in order to get the DNA  and to unwrap the proteins wrapping the DNA. The tube is then left in warm water bath for the lysis solution to work on the cell.

Centrifuge was used to spin the tube at high speed to separate the clump of proteins and cellular debris from strands of DNA.
Isopropyl alcohol is added to see the DNA with naked eyes .

2.PCR

Purpose of PCR is to make copies of DNA.
Primers were used in this experiment to attach to either ends of the DNA segment where you want to copy.
Nucleotides are used to make up the genetic code.
Polymerase were added to read the DNA codes and attach them to matching nucleotide.
To make the reactions work, the tube is placed thermal cycler for it to heat and cool at a certain temperature. When heated, the double-helix structure of the DNA breaks into 2 single strands. The primers mark and ‘lock’ the strands from rejoining.
At another temperature, the polymerase reacts by locating the primers and attach nucleotides to it and fall off once it gets to the end of the strand

3. Gel electrophoresis

This method is a way to measure the length of DNA strands. The gel is like a filter which filters out DNA. DNA samples are placed in the hole at one end of the gel and moves through the filter when electric current is activated. The gel contains salt solution which allows electrical currents to flow in the gel. Short DNA strands move through faster than long DNA strands. Over time, shorter DNA strands will be sorted out from longer strands as they move farther away from long strands and in groups.
To be able to see DNA with naked eye, staining technique can be applied.DNA length can be seen under UV light (with protective goggles) after adding DNA staining solution. The length of the DNA sample is then compared with the length of the DNA standard to have an estimation of the length of strands from DNA sample.

# data[].attributes.body
1. DNA Extraction
DNA can be used for genetic testing, body identification and analysis of forensic evidence. One area that we can isolate DNA from is on our cheeks. The DNA needs to be purified, as it contains protein and other cellular contaminants.

2. PCR
PCR is able to generate many identical copies of a specific DNA sequence. It works by heating and cooling the DNA solution over and over. Primer 1, primer  2 and DNA polymerase are added into the PCR tube to create the DNA copies. A DNA Thermal Cycler is used to precisely heat and cool the PCR tube at specific times.

3. Gel Electrophoresis
Gel electrophoresis is used to sort and measure DNA strands. Short DNA strands move through the holes in the gel more quickly than long DNA strands. The DNA strands in the sample sort themselves, according to the speed that they move. DNA moves through the gel towards the positive charge at the other end due to the repelling negative charges when the electrical current is turned on.

# data[].attributes.body
1. DNA Extraction
- Isolation of DNA is carried out for
a) Genetic testing
b) Body identification
c) Analysis of forensic evidence
- The main steps to purify DNA are:
1. Collect cheek cells
2. Burst open cells to release DNA
3. Separate DNA from proteins and debris
4. Isolate concentrated DNA
- The lysis solution is important in helping to release DNA from the cells as it contains 2 ingredients - detergent and an enzyme proteinase K. The detergent disrupts the cell membrane and nuclear envelop. This causes the cells to to burst open and release their DNA. Proteinase K cuts apart histones to release DNA.
2. PCR
- The purpose of PCR is to make more DNA copies. It works by heating and cooling the solution over and over so their tubes are designed for even heat distribution.
- PCR can be summarized into the following steps:
1. Add extracted DNA into special PCR tube.
2. Add Primer 1 to PCR tube.
3. Add Primer 2 to PCR tube.
4. Add nucleotides to PCR tube.
5. Add DNA Polymerase to PCR tube.
6. Put PCR tube into a DNA Thermal Cycler.
- Nucleotides are the A's, G's, C's and T's that make up the DNA code and are added as building blocks to create copies of DNA.
3. Gel Electrophoresis
- It is used to sort DNA strands according to length, as well as separate other types of molecules such as proteins.
- The "gel" is the filter that sorts the DNA strands.
- An electrical current is used to make the DNA move. That's why the process is called "Electrophoresis" which is how the DNA strands are pushed through the gel filter.

# data[].attributes.body
1. DNA testing is used for genetic testing, body identification and analysis of forensic science. Therefore, the DNA needs to be purified away from the proteins and other cellular contaminants.
The general 4 steps are, Collect cells, bursting cells to release DNA, Separating the DNA, and isolating the DNA to obtain a purified sample.
Lysis contains a detergent which disrupts the cellular membrane and nucleus envelope to release the DNA and the proteinase K cuts apart the histamines to free the DNA.
2. PCR is used to isolate specific segments of a particular DNA strand and it can generate up to 100 billion identical copies.
The PCR method generally works on heating and cooling cycles to help different reagents to copy the DNA and multiply. The DNA must be heated and cooled at specific timings during each cycle.
Primers attach to particular sites of the DNA that needs to be copies.
3. Gel electrophoresis sorts out and measures DNA strands. There will be a "gel" filter that helps sort out the DNA strands using electrical current to make the DNA strands to move as DNA is negatively charged, it will be inclined to move towards the positive parts of the gel, which is away from the gel cells.
Shorter DNA strands will end up further away from the gel cells as they can manoeuvre through smaller crevices of the gel, and the longer strands end up nearer to the starting point near the gel wells.
As individual DNA strands are very small, the DNA will form groups and form "bands" that can be better seen easily in the gel with the help of a staining agent.

# data[].attributes.body
1. DNA Extraction
DNA extraction is useful in many ways. It can be used for genetic testing, body identification and also analysis of forensic evidence. To extract DNA, firstly, cells must be collected, then burst open cells to release the DNA to be extracted. Next, seperate DNA from other proteins and debris before isolating and concentrating DNA.

2. PCR
PCR helps to make more DNA copies. this method includes a thermocycler which generates many cycles of heating and cooling, which heats up to 95 degress fahrenheit.

3. Gel electrophoresis
This method helps to sort out the DNA according to their length. DNA strands are pushed through the gel filter by "Electrophoresis". The strains are sorted and grouped together through postive and negative electric charges.

# data[].attributes.body
1. DNA Extraction
DNA is isolated for the following reasons:
a) Genetic testing
b) Body identification
c) Analysis of forensic evidence
DNA extraction is important because the DNA needs to be purified away from proteins and other cellular contaminants. DNA can be found in the nucleus from cells and it is about two meters in length.
The steps to purifying DNA are:
1. Collect cell
2. Burst open cells to release DNA
3. Seperate DNA from proteins and debris
4. Isolate concentrated DNA

2. PCR
PCR is performed to make more DNA copies. To perform PCR reaction, DNA has to be extracted from cells as we do not need much DNA to start the reaction.
2 primers will be added as each of the primer will be attached to either ends of the segment.

3. Gel Electrophoresis
Gel electrophoresis is to measure and sort DNA strands. The DNA strands are sorted and grouped together by negative and positive charges. Electric charges is required in order for the DNA to move along the gel filter.

# data[].attributes.body
1)DNA Extraction
Scientists isolate DNA  for genetic testing, body identification and analysis of forensic evidence.
Extraction of DNA is essential as DNA first has to be purified away from proteins and other cellular contaminants.
DNA is double stranded structure.

2)PCR
PCR is performed when DNA is extracted from cells where DNA was used to start the reaction.
PCR method involves a thermocycler which generates many cycles of heating and cooling.
This thermal cycler heats up to 95 degrees Fahrenheit, which is boiling temperature.

3)Gel Electrophoresis
DNA strands are pushed through the gel filter by “Electrophoresis”.
This method is effective for separating molecules like protein.
DNA strains are sorted and grouped together through negative and positive electric charges.

# data[].attributes.body
1. DNA Extraction
DNA are the genetic coding that makes up an organism. They are used for many reasons today such as genetic testing, study of a particular gene causing cancer or analysis of foreinsic evidence. DNA are found inside the nucleus of a cell and in order to obtain pure DNA strands; we got to first collect samples of cells from the cheek, simply because cheek cells are the easiest to obtain. Secondly we burst the cells to release the DNA and thirdly we use centrifugal force to seperate the DNA from the protein and debris. Lastly we isolate and concentrate the DNA to obtain the purest form of DNA strand.

2. PCR
The main purpose of PCR is to clone DNA and make many copies of it. This process is done so in accomodation of tools such as primers, polymerase and DNA. These tools help clone a particular segment of the DNA strand that some scientist use it for studying. PCR first occurs after DNA strand has been exposed to high temperatures whereby the DNA strands unzip and reveals the 2 strands DNA strips, the DNA strips then attempts to pair up. However, due to the presence of many primer in the solution. The primers obstruct the DNA strands from pairing up again and bond with their targets.

3. Gel electrophoresis
Gel electrophoresis is a method of classifiying DNA strand sizes uses a gel like filter which seperates the different sized DNA strands according to their lengths. This method uses electricity to move the DNA strands to the positive end of the gel through the repulson of negative charges within the gel filter. The shorter DNA strand will move through the gel first and will be the one that travels the furthest.

# data[].attributes.body
1.   DNA Extraction

In order to separate DNA from proteins and debris, the tube is placed inside a centrifuge, causing heavy clumps of protein and cellular debris to sink to the bottom of the tube while strands of DNA remain distributed through the liquid. A micropipettor is then used to remove the liquid containing DNA and it is placed into a clean tube.

2.   PCR

To perform a PCR reaction, we need DNA that has been extracted from cells. Since the purpose of PCR is to make more DNA copies, we do not need a lot of DNA in order to start the reaction. We can extract DNA from a small sample of blood, skin, saliva or hair follicles.

3.   Gel Electrophoresis

DNA strands are pushed through the gel filter by “Electrophoresis”. Therefore, we are able to make DNA move by adding electrical current.

# data[].attributes.body
1) DNA Extraction
The purposes for isolating DNA is to do genetic testing, body identification and analysis of forensic evidence. The steps required to purify DNA are
: 1. Collect cells
2. Burst the cells open to release the DNA
3. Separate DNA from proteins and debris
4. Isolate the concentrated DNA
2) PCR
The PCR method involves a thermocycler that creates many cycles of heating and cooling. This allows DNA molecules to separate and pair up and produce and generate 100 billion identical copies of a specific DNA sequence.
3)Gel Electrophoresis
The objective of electrophoresis is to sort out the DNA strands according to length. It can be also used for proteins.  DNA samples are put in holes at the end of the gel. With electrical current, DNA moves. The short strands will move further away quickly than the longer strands over time.  The 5 key steps of gel electrophoresis is:
1. Making the gel.
2. Setting up the apparatus.
3. Loading the DNA sample into the gel
4. Hooking up the electrical current and running the gel.
5. Staining the gel and analysing the results.

# data[].attributes.body
1. DNA Extraction
Lysis solution contains two important ingredient. Detergent and an enzyme called proteinase K.
Detergent: disrupts the cell membrane and nuclear envelope, causing the cell to burst open and release their DNA.
Proteinase K: frees the DNA from histones.

2. PCR
The thermal cycler heats up to 95 degrees Fahrenheit, which is boiling. At this temperature the DNA double helix separates, creating two single-stranded DNA and it will eventually generate 100billion identical copies of a specific DNA sequence.

3. Gel Electrophoresis
Electrophoresis is used whenever they need to sort DNA strands according to length. This method is also useful for separating other types of molecules, like protein.
"Electrophoresis" is how DNA strands are pushed through the gel filters. By adding an electrical current, we can make DNA move

# data[].attributes.body
i) DNA extraction:
DNA requires purification from any proteins or cellular contaminants in order to be isolated. DNA is found in the nucleus of cell hence the cell has to be burst open using lysis solution while contaminants can be removed via salt solution. Lastly, for DNA to be seen by naked eyes, isopropryl alcohol can be used.

ii) PCR
The main purpose of PCR is the multiply DNA to make many copies. The DNA thermal cycler is crucial as it can accurately heat and cool the sample at specific temperature for reaction to occur. Generally, at 95 °C, the double helix structure splits into two. At 50°C, primers lock onto target nucleotides be double helix structure can reform. At 72°C, the DNA polymerase is then activated to attach itself to the primer before adding complementary nucleotides. The cycle continues till cycle 4 where only target sequences are achieved.

iii) Gel Electrophoresis
The purpose of gel electrophoresis is to identify unknown DNA strands. Buffer allows electrical current to flow through the gel, creating one positive end and negative end. Shorter strand of DNA moves faster than longer strand of DNA to the positive end, hence sorting themselves. In the end, data can be analysed against standard DNA strand by staining the DNA and looking under UV light.

# data[].attributes.body
i) DNA Extraction
DNA is isolated for genetic testing, body identification and to analyse forensic evidence. It is vital to purify away protein & other cellular contaminants during DNA extraction. The four main steps in DNA extraction are 1) Collection of cheek cell 2) Burst cell open to release DNA using lysis solution 3)Separate DNA from protein and debris using salt solution 4) isolate concentrated DNA.
ii) PCR
PCR is a technique used to make over 100 billion identical copies of specific DNA sequence. DNA thermal cycler is used to heat and cool the PCR tubes at specific time. In the PCR tubes, at 95 °C the double helix separates, at 50°C dominant primer sequence lock onto target before single strand of DNA could join. At 72°C DNA polymerase is activated and adds complementary nucleotides until it reaches the end of the strand and falls off.
iii) Gel Electrophoresis
This method is useful when there is a need to sort DNA strand according to length. A DNA strand standard is used as reference to check the length of the DNA strand. DNA backbone is negatively charged thus when there is electrical current, it moves to the positive end. Staining by ethidium bromide is done as it can bind DNA and show up fluorescent light.

# data[].attributes.body
1. DNA Extraction

The purpose of it is for genetic testing, body identification and analysis of forensic evidence. DNA extraction is crucial because DNA needs to be properly purified away from proteins and other cellular contaminants.
Lysis solution contain detergent that will disrupt cell membrane and nuclear envelope, burst the cell and release DNA. Presence of proteinase K enzyme cuts apart histones to free DNA. Salt in this experiment clump protein and cellular debris together.
2.    PCR
PCR is to make more DNA copies. The DNA from PCR can be extracted from cells: blood, skin, saliva or hair follicles. The primer is the powerful tool to copy specific DNA sequences. The temperature and timing in the DNA thermal cycle is vital.  At 95 °C, DNA helix separates into 2 single strands. Then cooled down to 50°C, primer attach to DNA strands, thus strands are unable to rejoin. 72°C, DNA polymerase activated.
3.   Gel Electrophoresis
Purpose is to sort and measure DNA strands. As electrical current is activated, shorter strands will move quicker than longer strands. Over time, short strands will be located away from starting point. DNA strands of same length will then grouped together.

# data[].attributes.body
I) DNA Extraction
DNA is isolated for  many reasons like Genetic testing, Body identification and Analysis of forensic evidence. To start a DNA extraction, it first has to be purified away from proteins and other contaminants. There are 4 steps to purify DNA: 1. Collect cheek cells 2. Burst cells to release DNA 3. Separate DNA from proteins and debris 4. Isolate concentrated DNA.

II) PCR
PCR is a simple and economical way that is used to focus on a small segment of DNA and copy it to more copies. PCR undergoes 30 cycles to achieve the targeted amount of DNA sequence.

III) Gel Electrophoresis:
It is a method to sort and measure the DNA strands according to length in a test tube without seeing or touching them. This is also used for the separation of other molecules. The 'gel' used acts as a filter that sorts the DNA strands. The DNA will move by adding an electrical current. Short strands will move through the hole faster than the longer strands. The shorter strands will move further away from the starting point than the longer strands. The DNA strands will sort themselves as with the same length of DNA strands, they will move together at the same speed. Staining of gel is required so that the results are visible for analysis.

# data[].attributes.body
i) DNA extraction:
DNA is in the cells. To collect the DNA, we need to separate it from the cells. lysis solution contains detergent which will cause the cells burst open and release DNA. Proteinase K cuts down histones to free DNA.

ii) PCR:
PCR only need small amount of DNA that has been extracted from the cells to make more copies. Thermus aquaticus is a bacteria that used as DNA polymerase in PCR which well stand the heat and work well at 72 °C to make copy of cell's DNA before divided into two.

iii)Gel Electrophoresis:

It is a 5 steps experiment to sort  DNA according to their length using electrical current. DNA moves as it repelled by negative end. Shorter DNA strands will move farthest away. DNA with same length will move at same speed and group together at the end.

# data[].attributes.body
(i) DNA Extraction:

DNA is isolated to conduct genetic testing, body identification and analysis of forensic evident.

DNA isolation involved 4 stages namely collecting cells from test subject(skin of human mouth), burst open to get DNA, separate DNA from protein and debris, isolates concentrated DNA

Lysis solution contain detergent and proteases K where detergent disrupt cell membrane and nuclear envelope and cause cell to burst open and release DNA and protease K cut open histone to free DNA.

(ii) PCR:

PCR could be performed when DNA is extracted from cells where DNA was used to start the reaction.

The thermal cycle at 72 degree Celsius activate DNA polymer to attach to primer and add complementary nucleotide to DNA strand.

PCR undergoes 30 cycles to obtain the target sequence. Only 60 copies of the length molecule was obtained since there are only 2 desired fragment during cycle 3 and it continue to multiply to form 60 copies of the molecules.

(iii) Gel Electrophoresis:

Electrophoresis helps to sort DNA according to its length and measure DNA strand in the test tube since DNA is too small to be seen by the naked eyes.

Electrophoresis is where electric current is added to make DNA move since they contains oppositely charges namely positive and negative charges.

It has 5 steps namely make the gel, set up the gel apparatus, load the DNA sample into gel, hook up the electric current that run the gel, stain the gel and analyses the result.

# data[].attributes.body
I) DNA Extraction
The reason why scientists isolate DNA is for various purposes. For example, genetic testing, body identification and analysis of forensic evidence. The steps needed to purify DNA are:
1. Collect cheek cells
A swab was rubbed against a person's cheek and collected cheek cells.
2. Burst cells open to release DNA
The tube that contains cheek  is being placed into a hot water tub. Within the tube, the presence of lysis solution contains both detergent and an enzyme called proteinase K. The enzyme cuts the histones which are originally wrapped around the DNA.
3. Separate DNA from proteins and debris
Salt solution was added and the salt causes proteins and other cellular debris to clump together.
4. Isolate concentrated DNA
The centrifuge spins the tube at high speed while the heavy clumps of protein and cellular debris sink and the strands of DNA remain distributed through the liquid.
II) PCR
A PCR reaction is carried with the DNA extraction from the cells. The purpose of PCR reaction is to make more copies of DNA copies. PCR works by heating and cooling solution.
Cycle 1: The thermal cycle heats up to 95 degrees. DNA double helix separates creating 2 single stranded DNA. Then the temperature drops to 50 degree, single stranded molecules attempt to pair up. DNA polymerase is activated at the temperature of 72 degrees.
Cycle 2:  Temperature is raised and DNA separated. When the temperature is lowered, the primers will attach.
Cycle 3:
Intended products begin to appear, two strands that begin with primer one and end with primer two.
III) Gel Electrophoresis
Gel electrophoresis is being carried out to measure the length of the different DNA. Electrophoresis is how the DNA is being pushed through the filter. The addition of electric current allows the DNA to move. As shorts strands of DNA move faster, they will be further away from the starting point. In this case, the DNA are being categorized into different lengths.

# data[].attributes.body
(i) DNA extraction

In the process of DNA extraction , the tube that was spinning at high speed in the centrifuge will have heavy clumps of protein and debris stuck at the bottom of the tube after spinning is completed . With that the strands of DNA will remain distributed in the liquid .

(ii) PCR -
The main purpose of PCR is to assemble many more DNA from one DNA . Primers that are added to the PCR tubes are important as are able to copy the specific DNA sequences without making mistakes .

(iii) Gel electrophoresis

By adding electrical currecnt , DNA are allowed to move about . DNA moves towards the positive charge and repelled by the negative ones .

# data[].attributes.body
(I) DNA extraction:
We need DNA as the “priceless” genetic material for further recombinant DNA technology techniques such as the polymerase chain reaction (PCR). Once DNA is extracted, it needs to be purified to remove any unwanted contaminants that can interfere with further processes and giving us unreliable results.

DNA extraction involves four vital steps. Firstly, we need to collect DNA samples (in this case, from food?!), followed by using a suitable lysis solution to destroy the cell membrane and releasing the priceless DNA. Next is to use a suitable concentrated salt solution release an enzyme (Proteinase K) that acts like a tiny pair of scissors to snip off the histones, allowing DNA free itself from its protein “jail”. Lastly, the addition of an alcohol solution to separate the components of the DNA sample into two separate layers (just like oil and water since they hate each other, so they refuse to mix). This is how we extract DNA! :D

On a side note, I don’t know DNA can also be found from food.

(ii) PCR:
Polymerase chain reaction is a technique widely used in molecular biology to amplify DNA to make millions, millions and millions of its copies, forming one super big DNA family tree. PCR is an endless process that involves three steps,  denaturation, priming and extension to separate and replicate 2 strands of DNA.

One important thing is that we need to use a “heat-loving” bacteria (Thermus aquaticus) for PCR in order to survive the “denaturation” process, as most DNA polymerases that resides in our body are burned to death at temperatures below 95°C (We humans will also decomposed into tiny ashes, so…). The heat-loving Thermus aquaticus possess its own unique “superpower” that can survive at temperatures near the boiling point of water (Denaturation temperature is at 94°C).

(iii) Gel electrophoresis:
This step is a continuum from the PCR, where DNA fragments are isolated and inserted into cloning vectors. DNA molecules in gel electrophoresis are placed in a gel (often made of agarose) in the electrophoresis chamber that filters the DNA fragments by size and slows down the movement of DNA. Smaller DNA fragments move faster than its larger (or fatter) siblings, thus they travel farthest up the agarose gel. This helps to identify the DNA fragment patterns of individuals, which is used widely in forensics to rat out criminals in crime investigation cases.

# data[].attributes.body
i) DNA extraction:
To purify DNA from cheek swab, first you need to collect cheek cells by scraping the side of the cheeks. Secondly, burst the cell open to release DNA using lysis solution, followed by separating the DNA from cell debris. Lastly, isolating the concentrated DNA.
ii) PCR:
After DNA strand unzips due to high temperature, the single stranded molecules naturally attempts to pair up. However, there are many primer strands in the surrounding solution. The primers crowd their way in and bond with their target before the DNA strands rejoin.
iii) Gel electrophoresis:
Shorter DNA strands move through the holes in the gel quicker than longer DNA strands. Overtime, the shorter DNA strand will move farthest away. DNA of the same length move at same speed.

# data[].attributes.body
(i) DNA extraction: DNA which is not soluble in isopropyl alcohol will 'precipitate' or 'come out' of the solution when alcohol is added in order to be seen with the naked eyes.

(ii) PCR: A type of bacteria called Thermus aquaticus which works very well at 72 degrees and don't break down easily, is used as a DNA polymerase in PCR processes since the DNA polymerase in our bodies breaks down at temperatures very much below 95 °C .
(iii) Gel electrophoresis: The DNA strains are sorted and grouped together through negative and positive electric charges. At the end of the whole process, the base pairs estimation sizes of the DNA strains can be 6000, 3500 or 1,500.

# data[].attributes.body
(i) DNA extraction: The lysis solution contains proteinase K. The enzyme helps to free the DNA from histones which are proteins.

(ii) PCR: There are 2 primers added whereby each of them will attach to either ends of the segment.

(iii): Gel electrophoresis: In order to make DNA move along the gel filter, electrical current is required. Electrical charges are able to flow due to the buffer added.

# data[].attributes.body
Hope the virtual lab is useful in visualizing how DNA extraction, PCR and gel electrophoresis is done.

For attendance marking and sharing of learnings, please write down 3 things (one from each topic: (i) DNA extraction; (ii) PCR, (iii) gel electrophoresis; you have learnt from the e-practical)

The title of each post should be your name and class for easy attendance tracking.

Feel free to be creative in your posting! Click on the + icon on the bottom right to start!

# data[].attributes.body
1. DNA Extraction: for testing, analysis, identification ...

Blend food with salt water (eg. banana)

Add detergent/soap to break open cell membranes and nuclei

Add enzymes to separate protective proteins from DNA

Add alcohol (eg. isopropyl alcohol, IPA) to precipitate DNA

2. PCR: make multiple copies of the desired DNA part for diagnosis, identification, criminal matching ... Involves

Primers: short pieces of customised DNA

DNA Polymerase: a protein that copies DNA

Nucleotides: monomers of DNA for replication

https://goo.gl/images/9CGcWK

3. Gel electrophoresis: use of an electric field to separate DNA mixture into individual strands for analysis (eg. DNA evidences in crime scene)

Placed in a special gel with DNA molecules mixture located at the cathode (-ve electrode) side

Negatively-charged DNA molecules are attracted to and move towards the anode (+ve electrode)

Similar to a chromatography, the shorter/lighter the DNA chain, the faster it travels to the positive electrode, and vice versa.

https://goo.gl/images/a3wuV4
https://goo.gl/images/gf6QRX

# data[].attributes.body
1)DNA extraction: One of the lysis solutions which is detergent is used to disrupt the cell membrane and nuclear envelope, causing the cells to burst open and release their DNA.

2)PCR:
Nucleotides - The building blocks that DNA molecules are made of.  Four types of nucleotides with A's, C's, G's and T's are to be added to the PCR reaction. DNA polymerase grabs nucleotides that are floating in the liquid around it and attaches them to the end of a primer.

3)Gel electrophoresis:
The general steps for gel electrophoresis

1. Make the gel
2. Set up the gel apparatus
3. Load the DNA sample into the gel
4. Hook up the electrical current and run the gel
5. Stain the gel and analyse the results

# data[].attributes.body
(i) DNA extraction: DNA needs to be extracted from the cell and purified before the PCR process.

(ii) PCR: PCR involves 3 stages - Denaturation at 95degC, Annealing at around 55-65degC, Extension at 72degC

(iii) Gel electrophoresis: DNA moved from negatively charged to positive charged.