Building a DNA Model

    In my AP Biology class, our teacher tasked us with a unique way to build a DNA molecule. Half the class had instructions on how to build the molecule while the other half had the materials. We would be paired with someone who had the opposite of what we had, in order to work together to build a DNA molecule. One of the teammates read the instructions while the other constructed the molecule. I had received the materials to make the molecule. 

    When I pulled out the bag full of materials to build a DNA molecule I thought to myself, ‘How will I make a DNA molecule from these materials?’  I was pretty nervous to build my DNA molecule because I was not sure if my group would be able to communicate well. I have never done something like this before, so this added to the unpredictability of the task. However, my group worked well together and our communication was better than I expected. I actually finished my DNA structure quickly and was impressed with my team's fast progress. This experience was so unique because I was able to build something without the instructions and instead have someone read them to me through the screen. It was fun to be able to work with my peers on this simple yet complicated task. 

    

    The model of DNA that I created accurately represents an actual DNA molecule. The grey, green, blue and red straws represent the four different bases that make up DNA; Adenine, Thymine, Guanine and Cytosine. Adenine pairs with Thymine just like the grey pairs with the green and Guanine pairs with Cytosine just as the blue pairs with red. The DNA structure I built also shows the spiral like structure our DNA has. One of the sides of the structure has a “red ball” at the top while the other side has this at the bottom; this serves to represent how one of the sides of the DNA is 5’ to 3’ while the other side is 3’ to 5’. Attached below is a YouTube video that is very helpful if you would like to learn more about the structure of DNA!

While making this DNA molecule, I was thinking about the process of DNA replication. This process occurs in the nucleus and happens during interphase. A majority of the “key players” in this process are enzymes (this is evidenced by the names of the molecules; they all end in “ase”!) The first step in DNA replication is when the helicase protein unwinds the DNA. Then SSB proteins bind to DNA strands and primase creates the primer for the DNA. DNA polymerase is the protein that begins to build the new DNA. DNA polymerase can only work 5’ to 3’. The ligase protein is thought of as the gluer because it binds the new molecules to the DNA. The process of DNA replication is semi- conservative meaning that with the DNA molecule created, there is one original strand and one new strand. Attached below is another video on DNA replication if you would like to learn more about this process!