Molecular biology resources for hight school students electricity of the heart


The first step in investigating the DNA of an organism is getting it out of the cells. Remember that the DNA of most organisms is kept in the nucleus of the cell so we need to open up both the cell and nuclear membranes to get at it. electricity generation in california The biggest problem that we will face is the fact that the cell and the DNA inside of it is so small. We cannot just reach into the cell to get it. The other problem we will face is that there are a lot of chemicals in the cytoplasm that will breakdown the DNA if given the chance. Luckily scientists have figured out a way to get out just the DNA using a number of different chemicals. We will be using one such method today.

[ ]1.First we need to get some plant cells to get the DNA from. Each lab group has been provided with two plants to get their DNA from, one wild type (WT) and one mutant (MUT). For each of the plants we need to carefully obtain 50 mg (fresh weight) of leaves. To get them cut carefully at the base of the leaves and place them into a weighing dish. Make sure to label the two different samples.

Strangely enough all of the work that we did in the last portion of the lab didn’t produce enough DNA for us to be able to use it easily. This was a problem with DNA research for many years until in 1988 Dr. Kary Mullis, a surfer and scientist, came up with a revolutionary way to solve the problem. electricity 2pm live He created a process called PCR, or polymerase chain reaction, which is a way to make millions of copies of a segment of DNA in only a few hours. In this segment of the lab we will utilize Dr. Mullis’ discovery to make some copies of the gene in question. gas out game instructions Along the way, you will be given some explanations of how the process works.

• Taq DNA polymerase: This is the enzyme that assembles free DNA nucleotides in the solution into new strands of DNA. It comes from a hot-spring bacteria called Thermus aquaticus (thus the name Taq). This allows the enzyme to work at a wider temperature range, specifically at higher temperatures (remember that enzymes tend to be very specific about what conditions they will work in).

• dNTPs: These are DNA nucleotides that are not bonded to a strand yet. They consist of a phosphate group, nitrogen base (A,T,C, or G) and a deoxyribose sugar. Nucleotides are the monomers (building blocks) of the DNA polymer. You are basically including a soup of adenine, thymine, cytosine and guanine nucleotides for the Taq to use to make new DNA strands.

• Primers: These are short, single-stranded segments of DNA that correspond to sequences on the DNA strand to be copied. One primer corresponds to one end of the segment, the other primer to the other end on the opposite strand. The primers that we use are specific to the mutant gene AKT-1, or the sequence of DNA inserted into the AKT-1 gene that disrupts the gene, causing the mutation. The insertion is referred to as a “ T-DNA .” Use of primers specific for the T-DNA will yield a product if the DNA template has this mutation; i.e. the T-DNA insertion.

Now that we have made millions of copies of the gene in question, we need to see whether or not the gene is in the mutant plant. The problem is that we have a soup of DNA in our tubes along with the copies that we made in the PCR reaction. Remember that Arabidopsis has ten chromosomes (5 pairs), with a total of about 125 million base pairs, but we only wanted to look at a small segment of one of the chromosomes, about 900 base pairs long. We need a way to separate out the small fragment from the longer strands of DNA in the mixture. electricity recruitment 2015 Gel electrophoresis is just such a process.

Gel electrophoresis uses electricity and a Jello-like substance called agarose to separate out molecules based on size. First a gelatin block is made out of agarose. The sample of molecules, DNA in our case, is placed in holes in one end of the block. An electric current is then applied to the block with the DNA in it. 9gag memes The DNA is pulled through the gel by the electricity. The smaller pieces of DNA can move more quickly through the gel than the bigger ones can and that is how we separate them!

[ ]4.The agarose will not go into solution just from swirling; we will need to heat it up to get that to happen. Place the flask into the microwave and heat on high for 1 minute, watching the flask as it heats. It is important to watch the flask because when the solution begins to boil, it will boil out of the flask and make a mess. If you see the flask begin to boil, stop the microwave and go to the next step.

[ ]5.After 1 minute, or when the solution begins to boil, carefully remove the flask from the microwave and gently swirl the solution in the flask. Look to see if you can still se particles floating in the solution. If so, continue to heat the flask 15 seconds at a time watching carefully so that it will not boil over. If the solution is totally clear and you cannot see any particles swirling in the mixture, remove the flask from the microwave and let it cool on the countertop for 3 minutes.

[ ]8.Once the gel mold is ready to be filled you may begin filling your mold. Pour the agarose/TAE solution into the mold carefully. gas bloating diarrhea You want to pour enough to just reach the top of the teeth of the comb, but not over them. The combs will make wells in the gel so you can put your samples in. Once the gel is poured wait 10 minutes to let the gel harden.

[ ]15.You are now ready to load your samples into your gel. gas buddy For each of the samples, take all of the liquid out of the tube and carefully pipette it into one of the wells of the gel. Try to put your samples as close to the center of the gel as possible to get the best results that you can. Record the position of your samples in the table below so that you will know which is which.

[ ]16.Once the samples are loaded, you can place the lid on the electrophoresis chamber and plug it into the power source. When you are ready, turn the power on. Ask your instructor for the voltage to set your power source at for your electrophoresis. Record the voltage and time for your electrophoresis run below. The reaction will take a while to happen.

Another problem with DNA is that even in such large amounts it is not visible to the human eye. Scientists need to use dyes that will stick to the DNA to be able to see it. Many of the dyes that stick to DNA are harmful chemicals and need to be handled with great care. Luckily for us, we are going to use a slightly less dangerous chemical, methylene blue. gas natural fenosa As with the previous steps, check off the steps as you go.

[ ]3.After 30 minutes, remove your gel from the stain and place it into the water bath. When you take it out the gel will probably be very dark blue, don’t worry if you can’t see any DNA yet. It will remain in the water to “de-stain” overnight. As the gel soaks in the water the methylene blue will diffuse back out of the gel and into the water. The dye molecules that have stuck to the DNA will not be able to diffuse out, leaving bunches of dye where there is DNA in the gel.