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All living plants produce energy in their cells through the process of photosynthesis. This process takes place in the chloroplasts of plant cells, and consists of several chemical reactions that allow plants to harvest sunlight and produce carbohydrate molecules. This experiment used two model systems to study the effects of light on photosynthesis rates. The chloroplasts of spinach, also known as Spinacia oleracea, was the first model system studied. Spinach chloroplasts have been used as a model system in several experiments, including being used to study chloroplast DNA synthesis in relation to chloroplast growth and replication (Possingham,1976). The chloroplasts of kale, also known as Brassica oleracea, was the second model system used in this experiment. Kale is not widely used in laboratories when studying chloroplasts, but has been used as a model system in experiments involving the changes of chlorophyll pigment concentrations (Lefsurd, 2007).

Another observational difference between these two figures was the variation in the close up image of the spider web (Figure 1.D & 2.D). In the original image, the camera was held approximately 4-5 inches away from the metal rail to show the web in as much detail as possible. The replicated photograph was taken farther away from the metal rail, and the web cannot be easily seen. The replicate photo of the spider web was not taken where the original photo was taken. The original photo of the web was taken above the handrail, and the replicate photo was taken below the handrail.  

Figure 1. Original (1) and replicate (2) images made from following the methods section. (1.A & 2.A) The location of the spider web in relation to the Integrated Learning Center (ILC) and the Campus Center. (1.B & 2.B) The walkbridge connecting the ILC and Campus Center. (1.C & 2.C) White circle showing the precise location of the spider web on the walkbridge. (1.D & 2.D) Close up of the spider web woven into the grey metal bars of the walkbridge.

Students in Professor Bergan’s Writing in Biology class were tasked with finding a spider web somewhere on the UMass Amherst campus and photographing it. Students then created a figure including the photographs of the spider web and a detailed map to show its precise location. When the figure had been created, a detailed methods section was written that outlined the steps taken to obtain the photographs and create the figure. Next, the methods were given to another student who was instructed to follow them in an attempt to create a replicate of the original figure. The goal of this experiment was to compare the two figures that had been created by two different students and observe the differences between them.

The main objectives of this task were to practice writing different sections of a scientific research paper, creating clear and accurate figures that could be replicated, and following detailed methods written by someone else in hopes of obtaining the same result. Writing a detailed and accurate methods section about how the figure was created was crucial, and showed just how specific researchers need to be when writing methods sections that will be submitted for publishing. This exercise was aimed to show students how proper writing techniques are both valuable and necessary in the scientific community.  

When choosing a spider web to photograph, several factors had to be considered to ensure the proper recreation of the figure. These included the time of day, lighting, weather, and the type of camera used. The use of an object to represent scale as well as the orientation of the camera at the time of the photograph were key components of the experiment. Also important was the distance at which the camera was held in relation to the spider web and where the person was standing when they took the photo.

When outlining how the figure was digitally created, there were also factors that had to be accounted for to ensure that it could be replicated. The arrangement of the photographs in relation to one another, the borders separating them, and the use of letters to distinguish one photograph from another all had to be described.     Accuracy and attention to detail were essential for this experiment to be successful.

On page 1 there are two figures, each with 4 panels lettered A-D. Each picture contains a ruler and appears to be measuring a plant. The figure on the left is broken up into a top half and a bottom half, separated by a white bar. The figure on the right has pictures that are not touching and are all seprate. The letters are all located in the top left corner of each image. I can infer that the person who wrote the methods for this image wrote them well because these two figures are very similar.

The same plant is in both figures, and each lettered figure shows the same angle and part of the plant. They both use inches instead of centimeters to measure the plant. I can infer that these two figures were made to observe the lengths of various aspects of this plant, based on the observations of the ruler next to various parts of the plant. All of the pictures are taken from the same angle which shows that the methods were clear and direct. 

What makes some people more vulnerable to addiction than others? Until recently, this was not well understood by the scientific community. An international team of researchers recently published a study suggesting that the answer may be buried in our DNA. The paper describes an ancient retrovirus present in a higher proportion among people battling drug addiction. The researchers found that drug users were 3x more likely to have remains of the HK2 retrovirus within a particular gene than people who did not use drugs. This virus was found in 34% of the drug users that were tested, compared to 9.5% of the local population. It is thought that this retrovirus affects the RASGRF2 gene, which is involved in regulating the brains dopamine levels. Dopamine helps control the reward and pleasure centers of the brain, but is also involved in addictive behavior when it is generated in high amounts as a result of drug use. The researchers have not established a causal relationship between the retrovirus and addiction, but the correlation is very strong. With further research, the way that drug addiction is handled both medically and psychologically could change drastically.

When I was in high school, I got my first car. It was a 2003 Ford Explorer that my father passed down to me when I got my drivers license. It was not in the best shape, but it got me from where was to where I needed to go so I did not complain much. One day while I was sitting in the parking lot of a local pizza shop, smoke started billowing from under the hood of my car and a potent chemical smell filled the cabin. A light started flashing on the dashboard indicating that my engine needed to be checked. The temperature gauge on the dashboard went into the red zone, indicating that the engine temperature was getting too high. I turned off my engine and exited the drivers seat, only to find green liquid pouring out of my car onto the pavement. My inference was that a tube of some kind had broken off of where it was supposed to be attached. The car had a fair amount of rust on it, so I thought that the metal screws holding the tube in place could have rusted away over time and reached their breaking point. Sure enough, when I opened the hood of the car, there was the anti-freeze tube swinging freely and still pouring anti-freeze fluid out of the car. It was through the observations I made and then conveying them to my mechanic that he was able to fix my car so I could drive it again. I used my basic knowledge of a car engine to make inferences on what the problem could possibly be, and then used my observations to narrow down the possibilities. To fix the car, my mechanic relied on my initial observations of the problem, his secondary observations once the car was in his shop, and then his inferences to determine what steps he would take to fix the problem.

Figure 1. Butterfly with distinct markings on body & wings. The blue and red colors on this butterfly are located primarily at the back end of the body, and are used to distract prey. The symmetrical patterns on the wings are used to confuse prey and allow the butterfly to escape when being attacked.

"butterfly" flickr photo by davidyuweb https://flickr.com/photos/davidyuweb/4890215847 shared under a Creative Commons (BY-NC-ND) license