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Amino acids are the primary building blocks of all proteins. Each amino acid is comprised of a central alpha carbon with an alpha hydrogen, an amino group, a carboxyl group, and a variable R-group that makes them unique. The amino end is referred to as the N-terminus, and the carboxyl end Is referred to as the C-terminus. A total of twenty common amino acids exist within our bodies and they are sorted into different groups based on their chemical properties. For example, polar amino acids are considered to be hydrophilic (water loving) because their R-groups will interact with other polar molecules, including water. Amino acids polymerize with one another via a dehydration reaction and form a polypeptide chain comprised of anywhere from forty to thousands of these tiny building blocks. This is known as the primary structure of a protein.The aforementioned chemical properties of amino acids dictate how the primary structure will fold in an aqueous environment. Since the structure and shape of a protein is dependant on these R-group interactions and protein function is facilitated by shape, it is important that they fold properly. Therefore, the specific position of a given amino acid in the polypeptide is crucial for protein formation. Proteins cannot exist without amino acids and we cannot exist without proteins; amino acids are fundamental components of life itself.

One of the impacts of a hurricane such as the recent Hurricane Florence comes after the storm has passed. The flood waters can overtop places that people have sealed off to contain contaminants and as a result they are released into the environment. Such exampes of these quarantined spaces are waste facilities that can release toxic chemicals or hog lagoons, which farmers use to store feces and urine that are generated on the farm. The flooding causes these areas to overrun and releases contagious bacteria into the surrounding area and potential ruins the water supply. The environemntal impact on health may be better revealed as flood waters receded, but must be monitored in the interim. E.Coli, salmonella and giardia are all contagious bacteria that could be released. 

Another environemtnal hazard that could stem from the flooding is the contamination of water from coal ash. As coal is burned, it leaves behind ash that has toxic heavy metals and radioactive material. The ash is stored in a landfill, but similar to the hog lagoons, the flood water breached the walls and led to contamination. This allows for the spread of these toxic materials into the environment and results in exposure to people. The resulting materials could make its way into the groundwater and have lasting impacts on the surroundings or on drinking water.

Chondrichtyes are a class of cartilaginous fish which contains Holocephali and Elasmobronchii. There are about 40 extant species of Holocephali, one example being the ratfish. Female Holocephali are oviparous and will lay 1-2 eggs as a time. Males may be identified by the presence of claspers as well as a frontal tenaculum. The defining feature of the Holocephali is that they have a holostylic jaw suspension, meaning their upper jaw is fused with their braincase.

Elasmobrochii includes fish such as sharks, rays and skates. Although rays and skates are often placed into their own group known as the Batoids. This distinction is based on presence of gills on the sides of sharks, while rays and skates have gills located on their underside. All Elasmobrachi have placoid scales, that are similar to teeth in structure. Like teeth they have a pulp cavity, an enamel like substance that coats them and are even made of dentin. This has lead to the hypothesis that teeth are modified placoid scales, that migrated to the interior of the mouth. Of course, the opposite may also be true.

Diabetes mellitus is a disease that negatively affects the body’s ability to obtain energy from food. There are two forms of diabetes mellitus; type one and type two. Both of these types result from a defect in the negative feedback loop that regulates blood sugar levels. The negative feedback loop in a patient without diabetes works by using a sensor, effector, and control center. The pancreatic beta cells, which act as a sensor, detect an increase in blood sugar after the patient eats food. The pancreas also acts as the control center and is directed to release insulin into the blood. The insulin facilitates the reuptake of glucose from the cells, therefore, working as the effector to lower the blood sugar levels.

A patient with type one diabetes creates antibodies that destroy the pancreatic beta cells, therefore, damaging the sensor and control center of the negative feedback loop. As a result, the pancreas does not know to secrete insulin and leaves the blood glucose levels abnormally high. On the other hand, patients with type two diabetes do not have these antibodies; instead, they suffer from insulin resistance. In this case, the damaged part of the negative feedback loop is the effecter, as the cells do not respond to the insulin secretion. If the cells are not sensitive to the insulin, the glucose is not able to readily enter the cell, thus resulting in high blood sugar. In both cases, the damaged negative feedback loop fails to bring the blood sugar back to normal and can result in further complications. 

I believe the second biome is similar to the temperate deciduous forest. Which is most likely found between 30º and 50º N. In this area it is also important to note that it is limited to “on the eastern and western edges of Eurasia, and on the eastern edges of North America” (Bowman 65). This is because the further inland you go the more precipitation is lost which will affect the growth of trees. The main factor that led me to believe that it behaves like a temperate deciduous forest are the periods of sub-freezing temperatures. The sub-freezing temperatures occur between the months of December, January, and mid-February. In addition, I also noticed that there were no periods of time where it was insufficient for plant growth which supports the idea of tree growth. The mystery biome is described as having an annual precipitation rate of 1562 mm. If this biome is like the other biomes we have studied, I’d assume it contains trees such as oak trees which are deciduous and lose their leaves. This trait is important for the freezing temperatures. The mystery biome and the temperate deciduous forest are similar in many ways. 

The spider web was located under a small light post outside the stairwell to Morill 1, between the two Morill buildings. The photograph was taken with a camera phone as the sun was setting, when the light post had just turned on. This allowed the spiderweb to be seen much more easily than it would have been in complete daylight. Additional light from the light post aided visibility. Several photographs were taken from differing angles until a clear photo was taken where the spiderweb was mostly visible. Additional photos were taken, and were later reviewed for which was the best representation of the web. Some of these pictures included a ruler, which was held just below or to the side of the web. One picture was taken exclusively of the ruler against the light post, to give a measurement of the width of the light post and a scale of how large the web was. In order to give a sense of the environment the web was found in, and reference points as to were it was located; another photograph was taken of the light post as a whole, its general area and the door to the stairwell which lead up to Morill 1.

Diabetes mellitus is a disease that affects the way the human body obtains energy from food. There are two forms of diabetes mellitus; type one and type two. Both of these forms of diabetes are the result from a defect in a negative feedback loop that regulates blood sugar levels. The negative feedback loop in someone without diabetes works by using a sensor, effector, and control center. The sensor indicates that there is an increase in blood sugar which lets the pancreas, or control center, release insulin. Insulin acts as the effector, and facilitates the reuptake of glucose from the cells, therefore, bringing blood sugar levels back down to normal. However, a human with type one diabetes creates antibodies that destroy the pancreatic beta cells, therefore, destroying the sensor and control center of the negative feedback loop. As a result, the pancreas does not know to secrete insulin and leaves the blood glucose levels abnormally high. As for type two diabetes, insulin resistance leads to the increase in blood sugar. The damaged part of the negative feedback loop is the effecter, as it does not respond to the insulin. This decreased sensitivity to insulin makes the glucose not readily enter the cell and does not let the blood sugar levels return to normal after eating food.

During this experiment, we gave Tetrahymena India ink to calculate how much food vacuoles they formed when given different amounts of time to phagocytize. Under a microscope with the objective at 40x we counted and recorded the number of vacuoles formed. To analyze we looked at the time versus the number of vacuoles formed. After analyzation, it became apparent that the longer amount of time the Tetrahymena have in the ink before they're fixed the more food vacuoles that they will form. This information tells us that the Tetrahymena phagocytize consistently and the more time they are given the more food vacuoles that they will form.

Feedback loops are something that occur in many different aspects of life. They are an observation found in all different scientififc studies. This year alone I've learned about them in terms of human physiology and in climatology. Feedback loops are kind of like cycles. There is a signal that starts a chain reaction that leads to a response. Sometimes the response inhibits the initial siglanl, a negative feedback, and sometimes the response leads to an increase in the signal. An example of a positive feedback loop is chidbirth. The contraction leads to a nerve impulse that signals the hypothalamus to release the hormone oxytocin. The release of oxytocin leads to more contractions. Which then lead to more production of the hormone. The initial contraction leads to a stimulus that in the end results in more contractions. Blood clotting is another example of positive feedback because when a vessel is damaged platelets start to cling to it and when they cling they release a hormone that attracts more platelets. So the initial blood clotting leads to more blood clotting. The initial stimulus leads to an increase in the final product. 

Negative feedback has the opposite result. Negative feedback most often keeps something more towards equilibrium whereas positive feedback escalates, so usually only occurs in special instances. An example of negative feedback is thermoregulation. If a body temperature increase, measures are taken in order to try and lower the body temperature. So the initial increase leads to a decrease in body temp, therefore a negative response. Another example is blood sugar levels. When glucose levels are high, insulin is released to decrease levels. When levels are low, gllucagon is released to increase levels. The initial stimulus results in something trying to lower the signal. 

Methods and procedures play a huge role in scientific writing and research. Most of the information and knowledge we have obtained through history is because of scientific research and the ability to replicate that research. Experiments are an important aspect of science that allows us to obtain new knowledge and understand the world around us. In order for an hypothesis/experiment to be accepted, it must be able to be replicated. In order to do this, scientists must include a clear procedure of how they achieved their results. Within an experiment, there are variables that are changed as well as variables that must be controlled. The goal of this project is to practice writing informative and descriptive methods so others can understand and replicate an experiment. While we are not designing an experiment, we will be creating a multi-panel figure of a spider web found on the UMass campus as well as writing the methods we did to capture and create the figure. Once the methods are complete, each student will receive another student’s methods from their own and follow the procedure to hopefully create the exact same multi-panel figure as that student. The original multi-panel figure and the replicated multi-panel figure will be compared to see how accurate and descriptive the original methods were. This exercise allow students to see where they may need to be more descriptive in their methods and improve their scientific writing overall.