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This is demonstrated in Table 1 when the number of dyed food vacuoles within each cell increased as the time periods got larger. This was also proven in Graph 1 because the curve of the average number of dyed food vacuoles within each cell increases as the time advances. This reveals that the feeding rate of the tetrahymena increases as time progresses. After collecting all of the data, the average number of dyed food vacuoles per cell within each time period was able to be calculated by finding the mean. In addition, the standard deviation was able to be calculated for each time interval. This determines how far away the data was from the mean. Most of the standard deviations were relatively low numbers, showing that the data was accurate.

When a signal binds to a receptor, it undergoes a conformational change that leads to the desired effect on the cell it is attached to. Based on what we have learned about protein folding and the chemical interactions at the different levels of structure, I believe that these conformational changes that happen to receptors are similar. For instance, if the ligand that binds to a receptor contains a lot of negatively charged amino acid residues, it could repel certain parts of the polypeptide comprising the receptor. This would cause it to physically shift and take on a new conformation.

I wonder if the number of signals that meet at an integrator can vary? If there was say ten signals bound to an integrator versus 20, would there be a more rapid response? Or maybe there is a threshold that needs to be reached in order for the integrators to perform its function?

An example of this is how epinephrine travels through the blood and binds to a number of different cells in the body. For instance, the resulting signal cascade and effect epinephrine has on cardiac tissue is much different than epithelial tissue. Because of this, epinephrine (adrenaline) has a huge variety of different functions within the body.

Something that is interesting about receptor binding sites and their corresponding ligand binding partners is that shape plays a massive role. Similar to how a block fits into hole on a child's toy, each receptor has a specific binding site shape that corresponds with the signal that is meant to bind it. This ensures that molecules that fit into the binding site are the only thing that can bind. This goes hand-in-hand with ways that drugs interact within the body. Biochemists and pharmacologists design drugs to mock that shape of the binding partner of a given receptor to elicit a specific response within the cell and consequently the body.

I'm also a little confused by this concept, but I do know that tyrosine kinases are fundamental molecules that perform signaling transduction in a massive number of cellular pathways. It has the ability to transfer phosphate molecules, which are crucial units of energy within the cell. But I think that SH2 and SH3 are able to modify the activity of a receptor and consequently result in a more specific signaling cascade after something like a growth factor binds.

The Figure is made up of 3 panels which were put together with Inkspace. These panels allow the viewer to not only see the web, but also the surrounding area, and a map that shows where the web can be found. The first of the 3 panels is the web, as that was the main subject of the figure. Due to both the web picture and the environment picture being taken as vertical pictures, they were placed side by side while the map which was in the horizontal position was placed underneath. All of the panels were lined up at the corners to create a seamless presentation. In order to make which panel is which obvious to the viewer labels were placed. These labels were made in Inkspace. The different photographs included corners of different colors, so it was important to include a background to the letter labels. The background color that was chosen was white, so the black, uppercase, Arial font letter could stand out very well. For strictly aesthetic purposes the surrounding background that was chosen was circular and the opacity was put to 178 to allow some of the background of the photograph to show through. We read left to right so it was decided to put the labels in the top left hand corner of each panel. The map was the largest of the 3 panels, and takes up more of the figure than the top two panels combined. Once all of the panels were put together the largest side of the figure- which runs vertical was put to 1200 pixels.  

Homeostasis can be interrupted by either 1) an external change, leading to an internal change, or 2) just an internal change. This internal change leads to loss of homeostasis, which leads the organism to attempt to compensate. The compensation either 1) fails which leads to death, or 2) succeeds, which leads to homeostasis. 

The project undertaken for the Writing in Biology class was designed so students would photograph a durable object and document how the image was taken. They would then be tasked with writing a methods section to a level of certainty that they believed would allow another student to replicate the image. For consistency throughout the project, the subject matter of the photograph was limited to a spider web in relative close proximity to the Biology computer lab on the Umass Amherst Campus.

    In particular, the selection process of this spider web took into consideration the necessity of replicability and to ensure this, the spider web would need to be durable and last a period of, at minimum, several days. Therefore, a spider web inside a building was considered the most durable, as this would not experience any outside disturbances such as weather or movement that could potentially ruin the web that was photographed. In selecting the photo, the building that housed the biology computer lab was searched for a web that was slightly concealed so that any maintenance cleaning or foot traffic would ruin the web. One such web was found in a hole in an air venting system on the ground floor of the Morrill building. The hole in the vent had gathered dust suggesting it was untouched for a long period of time and gave the reassurance that the web would last the allotted time to allow for another student to find it. Furthermore, in writing the actual methods section, it was important to account for as many scenarios as possible and strictly limit them to what was actually performed in the photographing of the web. It sought to control the location of the photographer in conjunction with which photo should be taken, what the scale item would be and how it was located, the height of the camera and what the camera viewed in its lens all had to accurately be described so that the other student would be able to replicate the image as close as possible. The final figure that was made needed to be replicated as well, so the program used to make the multi-panel figure was recorded, as were the sizes of the images, the size of the font and labels, the colors used for the labeling and the overall layout of the figure.

After the methods were created by each student, they were randomly assigned to another classmate by Professor Brewer. Each student was asked to follow the new methods written by the classmate and create a figure of the spider web that they found. This part of the experiment resembled replication, as the students were tasked with redo the experiment to ultimately judge how concise and helpful the classmates method’s were. The students then observed the two figures of the same spider web and identified the differences between them.

The purpose of this experiment was to practice scientific writing through drafting the experimental methods and formatting figures. There were many factors identified that needed to be controlled in order to replicate the figures correctly. Some factors identified in the experiment included the exposure to sunlight, time of day, and weather. These affected the picture quality and color. The distance from the spiderweb and the camera angles were also factors that needed to be accounted for. These scaling factor was controlled by using some type of apparatus to measure the spiderweb in the picture.

The data supports the predictions for increased mitochondrial enzymatic activity and lipid oxidation pathways during hoary bat migration. Regarding enzymatic activity, the 29% increase in CS reflects greater aerobic capacity for powering flight, while the increases in CPT and HOAD prove that fat was used as a fuel during migration. Nonetheless, the hypothesized similarities between bats and birds concerning fatty acid transport are not supported by the data, since the studied proteins were expressed at similar levels throughout the year with the exception of H-FABP in females during migration. Such differences may be attributed to differences in the life history of hoary bats, and the increased expression of H-FABP in females may be due to pregnancy and torpor deprivation during migration, as well as for travelling larger distances than males.

The results showed an increase of oxidative enzymatic activity during migration, recording a 32% increment in activity for CPT, 53% in HOAD, and 29% in CS. As well, the enzymatic activity of HOAD was significantly greater in males. Regarding the mRNA expression of fatty acid transport proteins, the sequencing data showed a match of 90% or higher with already known genomes for H-FABP and FABpm, while FAT/CD36 matched at 80.5-87.3%. The mRNA expression of FAT/CD36 and FABpm remained stable throughout the year, but H-FABP showed changes in seasonality and differences depending on the sex of the bats. While males expressed constant levels of H-FABP independently of the season, females showed a fivefold increase during migration.
 

Additionally, the angle and positioning of the camera when taking the photographs must be acknowledged.

Methods

I entered Morrill 4 south and went up the stairs to the second level. I walked into the hallway and turned to the right, where I saw doors that led to the bridge that connects Morrill 4 to Morrill 2. If you look out at the bridge, on the left there should be a blue sign that has “Morrill 4 South” written on it. Underneath this sign is a blue radiator, which is where I found the spider web. If you stand facing the Morrill 4 sign and the blue radiator, the spider web is located on the bottom left side of the radiator attached to the pipe and black part of the wall. I placed a ticonderoga pencil on the ground, angled at roughly 15 degrees from the wall. I then held my iPhone, with the bottom of it resting on the ground, about 6 inches from the wall and faced it towards the spider web. I then took a photo of the spider web and the pencil with my flash on. To get a photo of the environment, I stood about 5 feet away from the blue radiator, closer to the stairwell than the doors to the Morrill bridge. I then angled my phone so I captured the blue radiator, most of the rug on the floor, the blue Morrill sign, and the left door that goes out to the Morrill bridge.

    Once I had the photos of the spider web I found and its environment, I used the UMass campus map, which can easily be found online.

I entered Morrill 4 south and went up the flights of stairs to the second level. I walked into the hallway and turned to the right, where I saw doors that led to the bridge that connects Morrill 4 to Morrill 2. If you look out at the bridge, on the left there should be a blue sign that has “Morrill 4 South” written on it. Underneath this sign is a blue radiator, where I found the spider web. If you stand facing the Morrill 4 sign and the blue radiator, the spider web is located on the bottom left side of the radiator attached to the pipe and black part of the wall. I placed a ticonderoga pencil on the ground, angled at roughly 15 degrees from the wall. I then held my iPhone, with the bottom of it resting on the ground, about 6 inches from the wall and faced it towards the spider web. I then took a photo of the spider web and the pencil with my flash on. To get a photo of the environment, I stood about 5 feet away from the blue radiator, closer to the stairwell than the doors to the Morrill bridge. I then angled my phone so I captured the blue radiator, most of the rug on the floor, the blue Morrill sign, and the left door that goes out to the Morrill bridge.