Lab+4+DNA


 * Exercise 1. DNA Replication**

1. Topoisomerase cuts a strand so the DNA can unwind. We placed the bead at the top and split the two strands of pipe.

2. Helicase utilizes ATP to melt the hydrogen bonds and hold the bases together. We exemplified this by placing the white coil around the top of the long strand.



3. Primase utilizes an OH- RNA Primer for Polymerase to attach and replication to be able to occur.



4. DNA Polymerase binds to one side of the DNA and guides nucleotides to bond with their complementary base pair and proofreads nucleus nucleus activity.



5. For Ligase the RNA primer is removed and filled in to catalyze a phosphodiester bond.




 * Exercise 2**

DNA Extraction from Wheat Germ



1. One can mix DNA with a chemical that mixes with DNA directly, like Ethidium Bromide. http://www.accessexcellence.org/AE/AEPC/geneconn/spooldna/proof.php

2. If one heats the DNA to 90 degrees Celsius Ultraviolet absorption will increase by about 260 nanometers. http://www.newton.dep.anl.gov/askasci/mole00/mole00687.htm

3. DNA stays dissolved in water but if one were to put it into contact with alcohol it is no longer dissolved. http://learn.genetics.utah.edu/content/labs/extraction/howto/

These methods are non toxic, except for utilizing Ethidium Bromide.

Additional Pictures:

DNA just after Alcohol placed in Test Tube




 * Exercise 3**


 * 2N 4N 2N**


 * 2N 4N 2N 1N **




 * Additional Pictures **


 * 2N (initial) **



4N

2N