Writing in Biology

SPECIFIC AIMS

1. Determine how different temperatures influence spider web size. Since spiders are an ectothermic species, temperature can have a large influence on behavior and physiological processes in the body. This study is studying how temperature affects spider web production and web size at 10°C, 20°C, and 30°C in containers. Web size was measured by weighing the container with the spider before web production began and then again after 5 days of web production.

2. Determine best temperature for web production. We expect to observe differences in web weight and production in the three different temperatures. Each spider will be kept in cups with a straw in it to help promote web production. For the 10°C condition, spiders in closed containers will be placed over ice and the ice will be replaced as needed. The spiders in the 20°C condition group will be kept in a room at 20°C. A heat lamp will be used for the 30°C group.

The goal of this project is to investigate whether the crab spider shows preference in the substrate it chooses. The preference that will be tested is color and complexity of the background.  It is known that the spider can change its color over the course of several days time from shades of white to yellow or vice versa depending on the spider's location. We will give each spider 2 choices in background color using yellow to white as the control. Other groups of colors that will be tested are dark gray and light grey, white and grey, cyan and green, and red and magenta.

Light entering from outside of the tank should also be the same on both sides. To keep this consistent do not place in sunlight, or somewhere that there are shadows. Overhead lights should be used because they will keep the light even on both sides. The lights should remain on 24 hours a day, so the spiders are always able to see the color of the background they are on.

To make sure that the spider strictly picks a side based on substrate color is it important to keep all other factors consistent. For example, temperature needs to be kept consistent inside of the tank. To do this, the spiders need to be kept away from windows and housed somewhere there is no breeze. It has been shown that spiders are less active in colder temperatures, so keeping them at room temperature (70°F) is important.

Transcription factors are amongst the proteins that help regulate the cell cycle. The E2F family of transcription factors are required for the cell to progress to the S-phase. The family is involved in the transcription of proteins that are required for the DNA synthesis stage of the cell cycle. The activation of S phase genes is an important checkpoint for the cell because it commits the cell to going through the cell cycle and is the checkpoint referred to as the “point of no return” for this reason. The E2F transcription factor is typically inactivated and bound to the pRB. However, when the cell is going through the cell cycle and is ready to enter the S-phase, Cyclin D promotes the kinases CDK4 and CDK6 to phosphorylate pRB. This causes pRB to no longer bind to E2F and E2F is then capable of functioning. After being released, E2F can transcribe the necessary proteins for S-phase. As E2F is important for the initiation of S-phase, it is also important in the inhibition of the cell cycle. Should an event occur where the cell needs to stop the cell cycle, such as the DNA being damaged, the cell will not commit to the cell cycle. At that stage, allowing E2F transcription would allow the DNA damage to be replicated and passed down. Therefore, the E2F family needs to remain inactive while the cell either fixes the damage or starts cell death. E2F is needed to progress through the cell cycle, but it is closely regulated so that the cell does not start the cell cycle process without the necessary requirements.

After recrystallization, TLC tests were run to see if 1,2-diphenylethane-1,2-diol was present in the products. TLC tests are used to determine the number of components in a mixture. The TLC plates tested are displayed in Figure 1. The first TLC plate, on the left of Figure 1, compares the starting material, benzoin, to the crude 1,2-diphenylethane-1,2-diol product. The spot indicating benzoin was larger and had moved across the TLC plate farther, resulting in a larger Rf value, than the spot indicating the crude 1,2-diphenylethane-1,2-diol product. This reveals that benzoin is less polar than 1,2-diphenylethane-1,2-diol. This is due to the carbonyl group that is present in benzoin. 1,2-diphenylethane-1,2-diol obtains an alcohol group in replacement of the carbonyl group on benzoin. This makes the compound more polar and less likely to move across a TLC plate, obtaining a lower Rf value. The second TLC plate, on the right of Figure 1, compares the starting material, benzoin, to the recrystallized 1,2-diphenylethane-1,2-diol product. The spots on the second plate were almost identical to that of the first plate because it is comparing the same compounds. One plate is using crude 1,2-diphenylethane-1,2-diol and the other plate is using purified 1,2-diphenylethane-1,2-diol. Both the crude and recrystallized plates resulted with only one spot in their lane. This confirms that there was only one component in the product, proving that the 1,2-diphenylethane-1,2-diol product was pure.

Carbohydrates are an essential part of the diet, for it fuels the body and brain with energy. Although it is essential to obtain a sufficient amount of carbohydrate daily, it is also necessary to be aware of the type and amount of carbohydrates consumed. Overconsumption of carbohydrates can not only lead to weight gain due to increased calories, but also an increased blood sugar. When carbohydrates are broken down in the digestive system it becomes glucose. A diet lacking carbohydrates may also yield detrimental effects. As reported by the International Journal of Obesity, although “protein has a similar energy density to carbohydrate” high intakes of protein in place of carbs has the potential to suppress food intake causing ketosis, where the body does not have enough glucose for energy and utilizes stored fat instead1. Based on the averages of the weekend and the weekday nutrients report approximately 50% of my diet’s calories are from carbohydrates, falling in the acceptable macronutrient distribution range of 45 to 65 percent of the total calories. Although the percentage of my carbohydrate intake is deemed acceptable according to the AMDR the sources of the carbohydrate intake is not necessarily healthy or nutrient dense. Based on my nutrients report half or a little less than half of my total sugar comes from added sugars. According to the American Heart Association, a women should consume no more than 25 grams of added sugar per day3. Keeping in mind that 25 grams is the maximum amount, it is recommended by the World Health Organization that the ideal intake of added sugars is less than 5% of one’s total calories3. In order to decrease the amount of added sugars in my diet I must choose foods that aren’t processed with lots of sugars. Added sugars are defined as any sugars or caloric sweeteners added to foods or beverages during processing or preparation. Instead of choosing to eat Quaker’s Chewy Bar as a snack, I could opt for an apple, orange, or some fruit that provides energy but also more nutrients. Not only do these fruits not contain added sugars like the Quaker’s chewy bar, but a medium-sized apple also contains about 4 grams of dietary fiber in addition to the carbohydrates it supplies. Additionally, instead of using granola as a part of  topping for my yogurt, I could use the original cheerios which is a great whole grain option. In comparison to granola, cheerios are minimal in added sugars, for honey and brown sugar is not used in the production process.

Because p53 and RB are so crucial to tumor suppression, their failure can be fatal. If either protein sustains a loss of function mutation, then errors in the DNA can make it past checkpoints. These errors can then lead to malfunctioning cells that cannot regulate their processes and become cancerous. Thus, both proteins are tumor suppressors.

For this scenario, a cell would need to receive a signal to divide. Since it is cloning itself for the replacement of a damaged cell, there must be a mechanism that releases division signals into the body. Perhaps this could be a signal released by the damaged cell itself or maybe another companion cell. What's important is that the replacement cell gets a signal to divide.

How does the cell accumulate extra cellular material to prepare for duplication? If it is increasing the rate of protein synthesis and doubling the cellular genome, where does it acquire all of the extra amino acids, nucleic acid, and other various cellular material?

It's interesting that the mechanisms of proteolysis can occur during the process of the cell cycle. This means that the proteins that add ubiquitin to other proteins functions during this period. These ubiquitinated proteins are then directed to the proteasome, meaning that the proteasome also functions during this time. They are lysed in the proteasome and degraded.

Cancerous cells take advantage of the failure of checkpoints and as a result accumulate more and more mutations. This is why cancerous cells are so hard to eradicate. Drugs can target specific players in specific pathways and disable them to prevent propagation of signals for growth, avoidance of cell death, and motility. But due to the mutability, cancer is able to adapt and utilize a different pathway or player to accommodate its needs for growth and spread. This is known as oncogene addiction.

Retinoblastoma (Rb) is an extremely commonly mutated protein in cancerous cells. Since it acts as a controller of a transcription factor for proteins (E2F)involved in the S phase of the cell cycle, when it has loss of function mutation it is not able to inhibit this TF. That is why Rb is considered a tumor suppressor.

The deaths for overdose in the next decade will be more than the victims of HVI. There is an actual crisis of addiction of medicines that derivate from opioids in the U.S. This will cause a half a million deaths in the next decade. According to historians, everything changed in January 1980 with the publication of a letter of 101 word in the prestigious “New England Journal of Medicine”, that affirms the addictive capacity of these derivatives in hospitalized patients was negligible. 

As a result, doctors began using narcotics more freely. Then a study suggested that narcotics could be used with few side effects in patients with chronic pain that weren’t in serious conditions. With less fear of its use, doctors were progressively prescribing narcotics to patients with all type of chronic pain. Then in 1996 the laboratory Purdue Pharma started selling Oxycontin. This marked a before and after the crisis of the aggressive marketing practiced of that pharmaceutical companies. 

The American society reacted too late to the narcotics addiction and only last month a law was approved by the senate to control the problem. The use of narcotics in a patient with severe pain is an absolute necessity, but the necessary padlocks must be put in place to prevent their uncontrolled use from ending up causing addiction in innocent people.

Addiction to narcotics, how did this lethal epidemic start in the U.S?

The deaths for overdose in the next decade will be more than the victims of HVI. There is an actual crisis of addiction of medicines that derivate from opioids in the U.S. This will cause a half a million deaths in the next decade. There should be something we can do to stop it and try to prevent it.