The percent yield could be increased by changing the ether used in the reaction. Although trimyristin and tert-butyl methyl ether have similar polarities, tert-butyl methyl ether has a higher boiling point than many other ethers. By substituting the tert-butyl methyl ether with another ether with a similar polarity to trimyristin and a lower boiling point, the heating process will be more efficient and there will be less contamination.
In addition, myristic acid was obtained from trimyristin via hydrolysis. 0.034 grams of myristic acid was produced, which resulted in a 60.7 % yield. The melting point obtained was 51-53 ˚C, which is slightly lower than the expected 54.4 ˚C, suggesting that contamination occurred. Although, the 2 ˚C range indicates relative purity, these results indicate that the product is most likely myristic acid.
To a clean round-bottom flask, trimyristin (0.056 grams), 6M NaOH (2 mL), 95% ethanol (2 mL), and a few boiling chips were added. After reflux for 45 minutes, the flask was cooled to room temperature. The solution was then poured into a 50 mL beaker that contained 8 mL of distilled water. Concentrated HCl (2 mL) was added dropwise to the beaker while stirring. The beaker was then cooled in an ice water bath with stirring for 10 minutes. The crystals were obtained via suction filtration and was rinsed with small portions of ice water three times.
A micro-scale filtration was performed in a 25 mL Erlenmeyer flask and the solution was filtered until all of the liquid has been transferred. Fresh tert-butyl methyl ether (2 mL) was used to rinse the flask. The solution was then obtained by using a gentle air stream to dry and yield the crude product.
The first recrystallization was performed using acetone (6.18 mL) and the solution was warmed until all the solids had dissolved. The solution was then cooled at room temperature for 5 minutes, and then was placed in an ice bath for an additional 15 minutes. After cooling in the ice bath, the crystals were obtained via suction filtration.
To a microscale round-bottomed flask, was added ground nutmeg (0.966 grams), tert-butyl methyl ethyl (3 mL), and a few boiling chips. Next, a black plastic connector was used to connect the distillation column to the flask. The flask was attached to a ring stand using a three-pronged clamp and was lowered into a small depression in the sand so it hovered above the sand bath. The mixture was heated gently for approximately 10 minutes.
4) What do the researchers think that their findings mean (i.e. how do they interpret their findings)
Ultimately, they determined that a cuckoo chick is able to predictably increase its call rate to offset its low gape area as these 2 features are the dominating factors that inform parents of nutritional needs. However, they are not fed as frequently as they would prefer and they suspect this is to avoid exhaustion of the host parents. Instead, they demand a similar amount of food as a standard warbler nest (4) for an extended duration. This is counterintuitive as a cuckoo chick does not have any stake in the survive of the host parents, but they suspect that a constraint must prevent the cuckoo from the predicted optimal feeding rates.
A coupled reaction is a series of connected reactions that share products and substrates. The reactions increase efficiency of energy transfer, and allows more points of regulation. The regulation is important for conservation of energy and resources for the cell. In order for a coupled reaction to be favorable, the net delta G must be overall negative. This means the pathways cannot be direct opposites of each other because than the pathway would have a slightly positive making it unfavorable. Also the pathway would then be futile and waste energy.
Glycogen degradation and glycogen synthesis have many similarities and differences. The main difference between the two is degradation is a catabolic reaction while synthesis is an anabolic reaction. Although the catabolic and anabolic reactions are normally thought of as one releasing energy the other requiring energy, Glycogen degradation and synthesis is a coupled reaction therefore the overall reaction would be releasing energy to make it favorable. Another difference is the use of different enzymes. Degradation uses the enzyme phosphorylase that breaks only the bond between an alpha 1 and 4 bond. Synthesis forms bonds with glycogenin.
3) What, exactly, did the researchers find (i.e., what were their data)?
In regards to the call experiment noted above, the researchers observed that there was a linear correlation between brood size and call frequency. They then created several regression equations in an attempt to quantify the impact of each factor. After manipulating the call rates of clutches they determined that the regression equation derived is: feeds delivered per hour = 2:28 (maximum number of gapes displayed) + 2.30 (maximum number of chicks calling) + 8.23. This equation was exclusive to 6-7 day old chicks so they manipulated the factors so that they could apply this to chicks of any age. The resulting regression equation thus derived was: feeds delivered per hour =0:0162 (gape area displayed (in mm2 )) + 0.178 (calls per 6 s) + 8.2. When analyzing the cuckoo chicks they determined that 1. A cuckoo chick intakes the amount that 4 warblers would normally require to survive and that a Cuckoo that is 6-8 days old has a call frequency that matches that of 4 warbler chicks. 2. This increased intake is not related to size, as black birds and song thrushes, even with augmented warbler calls, did not receive the same amount of food. However, in the presence of a cuckoo call they did receive more food. They then used the equation 0162 (gape area displayed (in mm2 )) + 0.178 (calls per 6 s) + 8.23, to determine if the cuckoo’s reduced gape area would in turn increase their call frequency in a predictable fashion.
The traps used will be a version of the pitfall trap described by Youngman et. al., 2009. The trap design is a cup firmly planted in a hole dug in the ground, with a second cup of the same rim width resting inside. In the interior cup, a small amount of ethanol will be placed to kill/preserve the specimens collected. Each team will set three traps at their chosen location, with each trap being at least twenty feet apart from the others.
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