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We examined color preference between cyan and green backgrounds, and white or yellow backgrounds. Cyan is a combination of green and blue at their highest intensities, while green is one of the primary colors in the RGB color model. Since we used a darker morph of crab spider for the cyan versus green trials, we hypothesized that the spider would prefer the green background.

White is a combination of the three primary colors at their highest intensities, while yellow is made with red and green at their highest intensity. Since we used a white morph of crab spider for the white versus yellow trials, we hypothesized that the spider would prefer the white background.

In many ways, RNA is the same as DNA. They both represent genetic information. They are kind of like different translations or languages of the same information. DNA has adenine, guanine, cytosine, and thymine. RNA has all the same expect thymine is replaced with uracil. Since they have so much overlapping similarity, it is thought that the first living organisms were made from RNA, and it eventually evolved to DNA. I never really considered that nucleotides would have other functions in the cell other than genetic information, but it makes sense. It makes sense that they would be involved in intracellular signaling and regulation of enzyme activity. I would think that transcription factors and things like post-translation modifications would be the nucleotides involved in signaling s well as enzyme activity. However, I wonder how nucleotides influence energy transduction. Hydrogen bonding and van der waals interactions help stabilize the structure of DNA and helps it maintain the double helix shape. Since two hydrogen bonds are between adenine and thymine while guanine and cytosine have three hydrogen bonds, G and C would be more stable. It is important for DNA to be able to denature itself as well as renature itself. This reminds me of an on and off switch. Denaturing means breaking apart DNA bonds/structure. Increasing temperature and signals can lead to the denature of DNA. Renaturing DNA brings the nucleotides back together.

There is a common chamber in which all six projects use to observe their spider. This keeps each experiment controlled and avoids any external factors that may skew the results. The chamber consists of a medium, square, Ziploc Tupperware. The Tupperware is placed upside down in order to ensure easy observation. A needle is heated with a flame in order to poke ten holes into the top of the container to allow air flow for the spiders. An additional larger hole was made in the middle of the container to allow the LED light to be placed in the chamber. This hole was made by repeatedly heating a needle and melting the plastic container to create a large enough space for the LED bulb to fit through. The LED light was held in place with masking tape. The light complex requires a small LED light, two jumpers, a resistor, and a 9V battery. Each spider chamber had its own light complex, placed to the side of the chamber in order not interfere with the LED light on the top of the complex. The LED light contains two needles that are inserted into one end of both jumpers. The other end of the jumpers obtain needles that resistors are wrapped around. The ends of the jumpers that are not attached to the LED light are then tapped to opposite ends of the 9V battery. This should illuminate the LED light. The LED light is inserted into whichever hole is designated to it in the chamber (this may be different depending on which project is being performed). Add two, three-inch sticks to each environment. One should be placed directly under the light, the other at one edge of the plastic container. Lastly, a cardboard box should be placed over each environment once they are completed. This stops any ambient light from entering the plastic container.

I am happy with my exam grade, but there are some things that I could improve on. When I was studying for the exam, I redid the homework problems and textbook problems. I also went through the class slides and went over any class activities that we did because these were helpful application problems. While studying, I also went through all of the objectives and wrote down all of the information I knew off the top of my head for each topic; I then studied more and added to the objectives as I studied new information. For the next exam, I am going to go over more problems that incorporate new concepts into the material. These questions will most likely come from the textbook. I will try to work with a study partner so we can come up with new ways of thinking about the concepts. It also helps to talk about the information because studies show that people who are able to teach a subject have a better understanding of it. Lastly, I will write out the “hows” and “whys” for the pathways and concepts. This way I will understand how and why the pathways happen in real life rather than memorizing the information. It is helpful to apply these concepts to real life and make the pathways sound like a story so that they are easier to understand. 

It's interesting that Okazaki fragment is able to not get lost in the process of DNA replication and become oriented perfectly in the newly synthesized DNA strand. There must be a series of cellular machines that keep this in the realm of possibility. However, I would assume that a good amount of the DNA errors that do occur are related to the Okazaki fragment, since the process is considerably more complex than synthesis of the leading strand (at least conceptually).  

This is really an amazing mechanism that happens within our bodies and within all other eukaryotic organisms. I wonder how the DNA polymerase is able to make the conformation shift to compare the newly synthesize strand to the original. Perhaps a ligand or even a phosphate group binding leads to the action of DNA polymerase. Also, this is far from the only proofreading mechanism that exists for DNA replication, which explains the incredible accuracy exhibited by the complex over the huge magnitude of DNA replicated.

Since this reaction requires a considerable amount of free energy to occur, it must be couple with a different process in the cell in order to be thermodynamically possible. Endothermic reactions like this need to be paired with an exothermic reaction to make the product formation favorable. All reactions need to have a negative change in free energy, the process of making that happen is called metabolic coupling.

I've read elsewhere that DNA polymerase is actually a series of enzyme subunits working together as a complex rather than a single enzyme. This makes sense when you think about it though. Considering that an enzyme typically corresponds with one reaction, there must be many involved to achieve DNA replication. DNA is a complex molecule and thus it would require a number of reactions and organization to achieve true replication.



 

Another function of helicase is to prevent the DNA in the process of replication from getting two wrapped up. Similar to how a rubber band is changed when both ends are twisted. When DNA is put into such a conformation it is unable to be copied due to the torsional strain on the molecule. Thus, it is critical that helicase performs this action as well as simultaneously working to separate the two strands of DNA.

We decided to analyze the energy expenditure of Ursus maritimus, commonly known as the polar bear. We were curious about how polar bears budget there time so we asked the question: What proportion of time is spent preforming high energy versus low energy behaviors by Ursus maritimus individuals. We wanted to know if they conserved their energy and how they spend there time. We hypothesized that Ursus maritimus individuals will spend a larger proportion of time performing low energy behaviors in order to conserve energy while active. 

Background Info:

Polar bears are a carnivorous maritime bear that resides on the arctic sea ice. They hunt primarily ringed and bearded seals because they require a high fat energy diet to survive. Polar bears have a thick layer of fur around their entire body in order to keep them warm and they also have a thick layer of blubber under their fur to provide insulation and buoyancy. They are currently listed as a threatened species due to declining populations of polar bears as a result of melting sea ice. There main food source is seals and in the summer they are in a physiological state of hibernation even though they remain active. This means they require less food because there body is feeding of the fat storages. 

The term crypsis englobes a multitude of strategies for avoiding detection by other animals by blending in with their environment. It plays an important role in predator-prey relationships, such as the interactions between crab spiders and bees. In this study we used a close relative of Misumena vatia, a crab spider widely studied for its color changing abilities, to investigate background color preferrence in swift crab spiders (Mecaphesa celer).

Like other crab spiders, Mecaphesa celer is an ambush hunter and it preys on pollinator insects by lurking in the flowers they visit. We hypothesized that in order to successfully capture its prey, Mecaphesa would choose to hide in flowers that more closely resemble its actual body coloration. In order to test our hypothesis, we designed an arena split into two different colors based in the RGB color model, and recorded to which side the spider moved after being placed in the center.

The goal of this review is to focus on selected new approaches and techniques for understanding how fish move through the water and to put these recent results into the context of classical studies of fish swimming. In particular, the review focuses on the analysis of the motion of the center of mass (COM), new approaches to imaging water flows in three dimensions (3D), and fish robotics as a means to understand the physical principles underlaying aquatic propulsion.

Changes in fin and body shape occur during fish locomotion, and can be used for studying patterns of fluid flow and developing computational fluid dynamic models of swimming fish. Undulatory swimming results in increased water velocity in the caudal region of the fish. The general form of the body wave that is produced during such movement is very similar among a diversity of fishes, such as the clown knifefish, eels, and bluegill sunfish.

There were three postulated methods of DNA replication that explained how genetic information was copied and passed down through the generations. The methods were semi-conservative, conservative and dispersive replication. Semi-conservative replication involved the double helix unwinding and each half becoming incorporated into a new strand of DNA while it served a s a template for what the other half should look like. Conservative replication suggested that the DNA double helix unwound to serve as a template for a new double helix, but that the original would wind back up and stay together and the replicated strand would be entirely new. Dispersive replication suggested that the double helix would be cut up and that the new strand would have pieces of the old strand of DNA and the newly synthesized DNA in it in no particular orientation. Meselson and Stahl investigated the idea of DNA replication and by using nitrogen markers, definitively showed that DNA replicated in a semi-conservative manner.