Writing in Biology

This project was aimed to asses the water quality and pollution levels of Sylvan stream using Periphyton. Periphyton are a class of aquatic microorganisms that grow in shallow slow moving water; they typically survive in water that has low to moderate pollution. We set up contraptions in three locations of the stream  that would collect periphyton and we observed the populations under a microscope after one and two weeks. The first location had the least and we believe this is because it was the closest to campus and had higher pollution. The third spot fell in the middle and the second location had the most. Overall there was high amounts of growth on the slides so we're concluding that the stream does have moderate pollution, however the levels do increase closer to campus. 

Heart disease is one of the leading causes of death in america. Valvular heart disease is a type of heart disease that revolves around the valves in the heart. These valves play a major role in controlling the flow of blood, and preventing backflow between the separate chambers. Although some heart valve issues can be fixed via drugs and therapies, sometimes patients have to get their valves replaced.  When a patient is considering this option, they can either get a mechanical valve or a bioprosthetic heart valve (BHV). Each option has its pros and cons, however BHVs offer more pros than the mechanical option. The main issue with BHVs is that they come from another animal, usually from cattle or pigs, and this triggers an immune response in the human body. This immune response leads to calcification of of the heart valve and severely reduces the shelf life of the prosthetic.

            After selecting primers for our gene, they were ordered from an outside lab source. The primers came back from this lab in 12.5 µL concentrations. Our extracted DNA had to be diluted first by adding ~5 µL of extracted DNA to ~45 µL of T₁₀E₁. However, Mutant B was found to be of very low concentration when run in the Nanodrop. For Mutant B only, no T₁₀E₁ was used to dilute the DNA sample and 2 µL of DNA was used alone instead. For Wild Type A, which had an initial concentration of 532.3 ng/µL, 5 µL of DNA was added to 45 µL of T₁₀E₁. For Wild Type B, with an initial concertation of 360.7 ng/µL, 7.5 µL of DNA was added to 42.5 µL of T₁₀E₁. For Mutant A, an initial concentration of 619.1 ng/µL, 4 µL of DNA was added to 46 µL of T₁₀E₁. With this exception, we calculated the diluted concentrations of each sample; Wild Type A had a diluted concentration of 53.23 ng/µL, Wild Type B 54.11 ng/µL, Mutant A 49.53, and Mutant B 2 µL undiluted at 6.5 ng/µL.

We studied the effects of urbanization on periphyton density and species richness in the local Amethyst Brook.  Amethyst Brook is a good site for a study due to it being conservation land where houses butt right up against some points of the river.  This allowed us to chose one site that represented close proximity to urbanization and two other sites farther away from human development.  We constructed a three-slide apparatus to place at each of the three sites, removing them at one and two week intervals. Microscope analysis of the slides provided us with multiple species types and overall density.  We hypothesized that urbanization would have an effect on periphyton in the brook, and predicted that there would be lower densities and less species at the site closest to houses. We also hypothesized that our week two collection would comprise of higher densities of periphyton.  Our data showed no correlation between periphyton density and proximity to urbanization. Interestingly, there was also a decrease in density across sites 1 and 3 after two weeks. This was due to heavy rains during the beginning of the second week that increased turbidity and strength of the water flow.  A more elaborate experiment with multiple sites and longer ‘grow periods’ would be necessary as a follow up to this pilot study.

Our data in the results section supported the information that was gathered from the studies researched by Lee, Lim, and Litwhiler. According to the luxury effect that affects the reptiles the strongest, the fourth floor should have the greatest number of arthropods since it is the closest to the reptile room. It also has the least amount of foot traffic which is another major factor. Because the first floor has the heaviest human traffic, there were the least amount of arthropods with only three spider webs combining both trials. The second floor only had nine arthropods or signs of arthropods. Third floor had twelve arthropods including dead bugs, live bugs, and spider webs. Fourth floor had eighteen including dead bugs, live bugs, and spider webs combining both trials for all three. Based off of our sources, our data proves the luxury effect and the theory that foot traffic along with the presence of reptiles reduces the number of arthropods.

Figure 10 summarizes the data of the four graphs. Figures 6 through 9 depict our data in graph form. The blue lines represent Trial 1 and the orange lines represent Trial 2. The first floor window sill is 21.33 m away from the reptile room, the second 19.69 m, the third 16.22 m, and the fourth 14.44 m. There was one crack present on the second floor.

The first graph, Figure 6, depicts the relationship between the number of dead bugs and distance from reptiles. In Trial 1 and Trial 2, zero dead bugs were found on the first and second floors. Two were found on the third floor in each trial. Four dead bugs were found on the fourth floor in Trial 1 and three were found in Trial 2. Therefore, a greater number of bugs were found on floors three and four when compared to floors one and two.

The second graph, Figure 7, depicts the relationship between the number of live bugs and distance from reptiles. In Trial 1 and Trial 2, zero live bugs were found on the first and second floor. In Trial 1, one live bug was found on both the third and fourth floor, and in Trial 2, zero live bugs were found on the third and fourth floors. Although few were observed, there was a greater number of bugs found on floors three and four.

The third graph, Figure 8, depicts the floor number versus the distance from reptiles. The first floor is the farthest from the reptile room and the fourth floor is the closest.

The fourth graph, Figure 9, depicts spider webs versus the distance from reptiles. Generally, there were many spider webs on the upper three floors for each trial with the least amount on the second floor.

In the spring 2018 semester of Dr. Stephen Brewer’s Writing in Biology course, students were tasked with designing proposal projects. Groups of students then voted on which project to base their poster presentation on. The purpose of the experiment we chose was to examine the relationship between the number of arthropods on window sills in Morrill IV South and their distance from the reptile room, which is located on the fifth floor of the Morrill II building. We observed the window sills adjacent to the bridge connecting Morrill IV North to Morrill IV South on the first, second, third, and fourth floors of the Morrill IV South building for signs of arthropods. These signs included live arthropods, dead arthropods, wings, exoskeletons, cracks, and webs, all of which will be quantified and related to the distance from the reptile room. Variables that influenced the number of arthropods and signs of arthropods include whether or not the window can open and the foot traffic of that particular floor. The aim was to find and explain the relationship between the number of arthropods on respective windowsills and their distances from the reptile room and to discover the ideal distance where arthropods thrive.

Our data in the results section supports the information that was gathered from the studies. According to the luxury effect, the fourth floor should have the greatest number of arthropods since it is the closest to the reptile room. It also has the least amount of foot traffic. Because the first floor has the heaviest human traffic, there were the least amount of arthropods with only 3 spider webs combining both trials. The second floor only had 9 arthropods or signs of arthropods. Third floor had twelve arthropods including dead bugs, live bugs, and spider webs. Fourth floor had 18 including dead bugs, live bugs, and spider webs combining both trials for all 3. Based off of our sources, our data lines up with the luxury effect and the theory that foot traffic reduces the number of arthropods.

First we counted the live arthropods, dead arthropods, webs, and cracks present on each window sill in two separate trials and created a table to quantify our data. The first trial took place on Tuesday, April 17th, and the second trial took place exactly one week later on Tuesday, April 24th. With the help of Professor Brewer, we were able to obtain the distance from all four window sills to the reptile room using Google Earth Pro. This program produced a 3D model of the Morrill II and Morrill IV South building.Using the arrows and ruler tool, the distance was measured. Because the reptile room was on the 5th floor, we had to take distance from all 4 different floors (1st, 2nd, 3rd, and 4th). Next we created four line graphs comparing Trial 1 and Trial 2. These graphs, Figures 1-4, respectively, are called Dead Bugs Versus Distance from Reptiles, Live Bugs Versus Distance from Reptiles, Floor Number Versus Distance from Reptiles, and Spider Webs Versus Distance from Reptiles. Figure 5 was created to put all the data together in one table.

The relationship between the distance from the reptiles to arthropods can be explained by other studies done in the past. An example of a phenomenon that explains this relationship is the luxury effect, which is strong particularly for lizards. Luxury effect displays links between urban biodiversity and sociology-economics (Litwhiler 2016). Studies have shown that factors such as climates and environmental factors play a key role when it comes to living organisms, and reptiles are no exception (Lee and Lim 2016). There are other factors that cause less arthropods, such as foot traffic. Since the first floor being the floor has the most traffic, it will have the least number of arthropods or signs of arthropods, as compared to the 4th floor that doesn’t have as much foot traffic. Since foot traffic causes a disturbance of other living organisms, there are less arthropods present. By critically observing and counting up the numbers of the arthropods and how they contain different physical features whether they be live or dead, we can observe and study how the relationship of the two affects each other.