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Sandra Peterson also does research, mostly about brain signals that influence ovulation. Research in her lab focuses on three main things, one of which being the molecular and cellular mechanisms that underlie the brain signals that control ovulation. When ovary follicles mature, they begin to release estradiol. This release of estradiol triggers signals that activate hormone neurons, which then activates the release of luteinizing hormone from the pituitary gland. In order to trigger the signals, the estradiol targets specialized neurons called GABA/Glutamate neurons. The luteinizing hormone is what actually triggers ovulation. In her lab, they are currently researching how estradiol and daily signals work together to change the rates of GABA in vivo and in vitro.

Her lab also researches the developmental mechanisms responsible for sex differences in the brain that cause ovulation. The differences in the brains that are most visible can be seen with the GABA/Glutamate neurons. Her team’s work suggests that female brains have twice as many GABA/Glutamate neurons than male brains. They also discovered that exposing the GABA/Glu neurons to testosterone around birth reduces the ability the release the luteinizing hormones. Lastly, her lab focuses on how environmental contaminants can interfere with the the development of the brain region that controls the release of gonadotropins. The main contaminant that her lab focuses on is dioxins. Dioxins are very strong environmental pollutants that come from manufacturing processes. They recently found that dioxins can bind to the GABA/Glutamate neurons and cause males to retain the female neuroanatomy.

The question that I chose was “Why does this graph level off?” This question appears in Lecture 10, on slide 12. It also has a diagram of a graph with [substrates] as the x axis and initial velocity as the y axis. The concept that is being tested by this question is the students ability to interpret enzyme activity graphs. In order to to answer this question correctly, you need to understand how to interpret what a changing substrate concentration does to an enzymes Vmax. Understanding what initial velocity means is important. You also need to understand what Vmax means, because knowing that will eliminate some of the incorrect answers. Understanding what would cause an enzyme's rate to slow down would enable you to answer this question.

For this question, the correct answer is B, enzyme active sites are filled. This is correct because the enzyme reaches Vmax when the graph is starting to level off. Vmax is reached when the enzymes in the system are all working at maximum rate, which is when all of the enzymes are filled. Answer A, “the substrate is used up,” is incorrect because where the graph levels off, the substrate concentration is not zero. In addition to that, the y axis is initial velocity, which means there would be no time for the substrate to have been used up. Answer C, “the reaction reaches equilibrium,” is incorrect because the graph makes no mention of the reverse reaction, and thus no mention of equilibrium. The graph only illustrates the rate of the enzymes which are performing the forward reaction. Answer D, “the rate of the reverse reaction becomes significant” is incorrect because that would indicate that the graph illustrates a system over time. The y axis shows that the dots mean initial velocity, which means that the reverse reaction would not have time to become significant.

The University of Massachusetts Amherst is teeming with great faculty, which is what makes it such a great university. All of the great faculty made it difficult to choose one person to write about. However, after searching through the MCB faculty list, I found Dr. Sandra L Peterson. Sandra Peterson is a Professor of Molecular Neuroendocrinology of reproduction at UMass. Sandra Peterson got her BS in Biology at Rutgers University in 1977. She then went on to get her MS in Neuroendocrinology at Oregon State University in 1980. Finally, she followed that up with her PhD in Neuroendocrinology at Oregon State University in 1984.

In addition to being a professor, she is a director at the STEM diversity institute. The STEM diversity institute’s main purpose is to facilitate the diversification of the STEM workforce. They help underrepresented groups enter and rise in the STEM field. Sandra is also a director at the Northeast Alliance for Graduate Education program (NEAGEP). Similar to the STEM diversity institute, the NEAGEP works to recruit and mentor members from minority groups and help enable them to pursue PhDs in the mathematics, engineering, and science.

In scientific writing, a methods section is one of the most important parts of a research paper, because it allows the project to be recreated. Recreation of a scientific project is the first step towards turning an experiment into a theory or a scientific law. In Spring 2018, for a Writing in Biology class at University of Massachusetts Amherst, the main goal was to design a figure about a plant and include a methods section along with it that would allow another person to recreate the figure with a high degree of accuracy. The figure that was recreated included photos of a plant and its geographical range. The plant that was used is a Blc Momilani ‘The Gypsy’ and it was selected because of its ease of access.

An important part of designing the methods was maximizing the number of factors that could be controlled. This would then enable the other student to recreate the figure with a higher degree of accuracy. These factors include the ease of access to the subject and the reliability of the subject. When it comes to ease of access, the greenhouse where the plant is found is open for most of the day on every week day, so the other student would be able to find time to take a picture of the flower. In the case of the reliability of the subject, the plant is in a climate controlled area, and it is watered and taken care of every day. Because of this prime environment, there was a very high chance that the plant would still be alive when the other student went to take a picture of it. This is better than if the plant was outside, where it could die or be ripped out of the ground.

The Spring 2018 Writing in Biology Class Methods project focused on the importance of a methods section in scientific writing. One student made a figure and wrote a methods section that would allow another student to recreate it. The student made a figure the Blc Momilani ‘The Gypsy’ flower that is located in the Durfee Conservatory on the University of Massachusetts Amherst Campus. When another student recreated the figure of the plant, differences were observed in the labels of the figure, which were a consequence of an unspecific methods section. Photography was also another way in which the figures were different. The differences in the photos taken of the plant were because of different cameras used and an unspecified description of how to take the picture. Finally, differences were observed in Part C of the figures. The differences in Part C were caused by directions in inkscape that were impossible to perfectly recreate.

In the results, Figure 1 refers to the original figure, and Figure 2 refers to the replicate figure. Figure 1 and Figure 2 look somewhat similar, however they bear differences. The differences observed will be sorted in paragraphs, about the labels, photography differences, and differences in part C of the Figures.

When looking at the labels, in Figure 1, the letters are black and have a white square behind them, while in Figure 2 the letters “A” and “B” are in white font, and the letter “C” is in black font. On the same note, the letters are bigger and less tightly organized in Figure 2. In addition to that, the background of Figure 2 is transparent, while the background of the Figure 1 is white. In Figure 1, there is no empty space in between photos A, B, and C. However, in Figure 2, there is white space between photos A and B, and between photos B and C.

Looking at the photos of the plant and flower itself, in Figure 2, the pictures of the plant and of the flower are brighter than Figure 1. In addition to that, Figure 2 is more blue shifted while Figure 1 has warmer tones to the photos. In Figure 2b, the flower is smaller than the flower in Figure 1b. Lastly, in Figure 2a, the top of the flower pot is less cicular than the top of the pot in Figure 1a.

All of the differences between these two figures have reasons behind them, and most of them are because of an unspecific methods section. For example, when it came to the discrepancies in the labels on the image, it was because the methods did not describe what color or size the letters should be. In addition to that, the methods did not include that there was a white square placed behind the letters in order to distinguish them from the picture. In addition to that, the space between the photos is because the methods didn’t specify how close the pictures should be in the figure. This could have been fixed by including the coordinates and sizes of the images when they were arranged on inkscape in the methods.

Many differences can be seen when comparing the photo C of both figures. In the original figure, all of the highlighted areas have labels and arrows pointing to them, while those are absent in the replicate figure. The lines that encircle the areas on the map are larger and less smooth in the replicate image. In addition to that, the circled areas of the original figure are completely filled in with the color, while in the replicate there is only color on the landmass encompassed by the circle. In the original photo, there are red, green, and purple stripes where all three areas overlap. However, in the replicate figure, there are only patterns of red and purple stripes and green and purple stripes, and no areas where all three of the colors are represented.

The replicate and original figures look somewhat similar, however they bear many differences. One difference is the labels in the corner of the images. In the original figure, the letters are black and have a white square behind them, while in the replicate figure the letters “A” and “B” are in white font, and the letter “C” is in black font. On the same note, the letters are bigger in the replicate figure. In addition to that, the background of the replicate figure is transparent, while the background of the original figure is white. In the original figure, there is no empty space in between photos A, B, and C. However, in the replicate, there is white space between photos A and B, and between photos B and C.

In scientific writing, a methods section is one of the most important parts of a research paper, because it allows the project to be recreated. Recreation of a scientific project is the first step towards turning an experiment into a theory or a scientific law. In this project, the main goal was to design a figure about a plant and include a methods section along with it that would allow another person to recreate the figure with a high degree of accuracy. The figure that was recreated included photos of a plant and its geographical range. The plant that was used is a Blc Momilani ‘The Gypsy’ and it was selected because of its ease of access. The most important variable to control in making this figure was it being simple and reasonable for the other student to recreate. The greenhouse where the plant is found is open for most of the day and the plants are well taken care of, which provides a good environment for a plant that needs to be photographed. If the plant was found and photographed outdoors, there was a risk that it could have died or been removed by the time the other student could have attempted to recreate the figure.