Drafts

Monogamy: As previously mentioned, sexual selection is most intense in polygamous relationships as seen in leks and due to these intense pressures this is seen in less than 10% of all avian species. The alternative, monogamy, revolves around a bonded pairing of individuals that cooperate to copulate and raise their young as this is occasionally essential for the offspring to survive.. Males typically hunt, defend their territory and even assist with incubation in some scenarios and the females will determine the viability of their partner based on these efforts. Once formed, the duration of these bonds can vary with some relationships lasting only for the breeding season and other lasting for life. Despite the superficial appearance of monogamy, there are frequent episodes of “extra-pair copulation” by females who willingly accept advances from other males. On average, only 14% of the offspring in a nest are the offspring of the tending father. This is done by females to ensure variability and viability of their young and males participate in this behavior so as to pass on their genetics as frequently as possible.

HeLa cells were stolen from Henrietta Lacks without her knowledge or full consent, while she was in John Hopkins hospital seeking radium treatment for her cervical cancer, scientist George Gey sought the opportunity, while Henrietta was unconscious during surgery, to have a surgeon collect her cancerous tissue cells to be used for his research on growing a human immortal cell line. To Gey’s astonishment the cells grew perfectly and survived longer than any of the cells he had cultured before, and the rest is scientific history. Yet what science seems to forget is the woman behind the cells and how unethical scientific research was during the 1950’s to the early 1990’s. During that forty year time span many critical and obstructive research occurred all over the United States and possibly all over the world with no laws or pre-dispositions to help regulate the safety and prosperity of the subjects.

Lek Displays:  While many courtship displays occur in pairs, the most extreme cases of sexual dimorphism occur when courtship displays are done in large groups with multiple members of the same species. These large masses of courting displays are known as Leks and due to the extreme competition among the males in these groups there is additional emphasis on dominance and attractive morphology. Typically, a small number of males are selected for and sire the vast majority of the upcoming generation. As previously noted, natural selection favors those with the highest reproductive success so one must question why a subordinate male would continue to reside in these Leks if unsuccessful.  Studies have shown that females typically favor larger groups of males and subordinate males do have a minor chance to reproduce simply by being in the presence of a dominant figure. Of note, leks are typically more closely related to each other than other individuals in other leks and theories proposed by Paris Hamilton suggest that a subordinate role is tolerated more easily if the dominant male has similar genetics as this qualifies as reproductive success in a sense.

Good Gene Hypothesis: Courtship displays are ancient reproductive strategies that have been tightly associated with elaborate plumage. This elaboration is meant to convey superior fitness to females, however, the mechanism of this is unknown. The prevailing theory detailing this correlation is the “Good Gene Hypothesis”.  This theory suggests that exotic or more elaborate plumage serves as a handicap by making them less optimal for flight or running as well as more easily identifiable by predators. However, if a male is able to survive with these additional stressors then a female can infer that they are superior in terms of stamina or survival skills.  Furthermore, this theory suggests that plumage can reveal parasite load and hormonal levels as they have both been shown to affect brilliance or color scheme. Due to the high associated cost associated with developing, maintaining and surviving with such elaborate feather schemes, many species have developed post-breeding molting cycles to eliminate these handicaps during the non-breeding seasons.

Although quantitative analysis was not possible for fixed NIH 3T3 cells treated with TMR-dextran and lysotracker. This could have occurred due to possible insufficient exposure time and binning combinations when capturing images, or insufficient incubation time and conditions for the lysotracker and TMR-dextran. However, based on previous studies and common science knowledge, we are able to infer what visual and quantitative data of this investigation should resemble. After 15 min. of incubation time, the average total intensity of the TMR-dextran should be high at the surface of the cell relative to the interior. This is due to the relative brevity of the incubation time, where has not been sufficient time for many of the dextran molecules to be invaginated into the cell’s luminal space. The interior images should also display a relative high intensity of lysotracker at this point. After 75 min. of incubation time, the average total intensity of the TMR-dextran should be high at the interior of the cell relative to the surface. This is because the cell has had sufficient time to invaginate a majority of the dextran molecules and form endosomes and protonate, bringing them into the cell’s luminal space and closer to lysosomes. At this point, the interior images should display high lysotracker total intensities and high dextran total intensities, which would confirm that the dextran migrated to the inner most part of the luminal space.  

Live LLC-Pk1 cells with GFP tagged tubulin were treated with TMR-dextran. Control group cells were incubated with solely TMR-dextran, while treatment group cells were incubated with TMR-dextran, and subsequently incubated in nocodazole. Both groups were time-lapse imaged at 40X magnification for 300 s (1 frame every 10 s). Vesicle movement was then quantitatively analyzed using ImageJ’s “TrackMate” plugin to measure total displacement of vesicles (Figure 5). Cells treated with nocodazole demonstrated a lower average displacement of vesicles compared to control group cells (0.164µm, 0.716µm, respectively) (Table 1). Composite image frames of start, middle, and end of the time-lapse image series visually display the differences in movement of the vesicles over time across groups (Figure 4).

Mates: Different investments between females (few # of costly eggs) vs males (high number of low cost sperm) naturally create both sexually dimorphism and behavioral differences between the genders. Natural selection favors those with the highest reproductive success and typically, birds form lifelong mated pairs that cooperate to raise their young as they require assistance to do so. However, as males will have higher success by finding multiple mates they often engage in cross pair copulation with other females. Furthermore, females have ways to protect their larger investments by selectivly choosing their "partner" as well as secondary partners. It is this "choosy" behavior that has driven the extravagant courtship displays seen in the wild. In addition, females will often breed with several neighboring species to ensure that at least some offspring are viable.

The TLC analysis, the solvent that was proven to be the best was 95% Hexane, 5% Ethyl acetate although it the ratio between the two compounds was not perfect for separation of the products. The solvent that was proven the best was 70% Hexane, 30% Ethyl acetate. This solvent showed a greater separation of products and distinct identity of each product in lane B compared to lanes A and C. 

In this lab, an Sn2 reaction took place with 2-naphthyl as the nucleophile which displaced the iodide to form butyl naphthyl ether and sodium iodide. The percent yield I obtained from this experiment was 13.6%. The percent yield is relatively low. The first reason my products yield was low was because the melting point was very low, I noticed that as I was weighing the product some of the product melted on the filter paper. I could have avoided the loss of product this way by being more careful when handling the solid product and making sure no heat was applied to it. Also the addition of NaOH before refluxing is important so the product is properly deprotonated so that the product does not become oil when recrystallizing. If the product is oil instead of crystals then the product would go through the filtration. The melting point obtained was 31- 33⁰C. Compared to the melting point of butyl naphthyl ether which is 33-35^oC, the product produced in this lab was close in range to the one given to us. Therefore, my product is mostly pure although the discrepancies between the temperature given to us and the one obtained in the experiment can be explained the presence of possible impurities that are left in the product.

Both 2-naphthyl and the product produced were dissolved in ethyl acetate. Then on three TLC plates put in one lane just the dissolved 2-naphthyl, the second lane is two spots of both dissolved 2-naphthyl and dissolved product, and in the third lane the dissolved product. The first plate is dissolved in the solvent of 95% ethyl acetate and 5% hexane. The second plate is dissolved in the solvent of 95% hexane and 5 % ethyl acetate. After analyzing which solvent worked better which was 95% hexane and 5% ethyl acetate, the ratios were changed to get the best results. The final plate was dissolved in 70% hexane and 30% ethyl acetate.