Orgo Lab

Submitted by hamacdonald on Fri, 11/17/2017 - 14:39

 

 

Purpose:

 The purpose of this experiment is to isolate and recrystallize trimyristin from nutmeg and then hydrolyze the trimyristin in a mixture containing 6M NaOH, 95% ethanol, and HCL to form myristic acid.

Reaction Scheme:

 

Procedure:

            In a 250 mL round bottom flask, nutmeg (1.010 g, 2.29 mmol) and tert-butyl methyl ether (3 mL) were added and boiled for ten minutes. Once the solution had boiled and cooled, the liquid layer was filtered into a 25- mL Erlenmeyer flask via microscale filtration techniques. Tert-butyl methyl ether (2 mL, 22.69) was added to the round bottom flask, heated, and filtered again (percent recovery, 24.578- 24.107). After the second filtration, the 25- mL Erlenmeyer flask was warmed and air was blown over the solution until all of the solvent evaporated and the solid yellow product remained. The product was dried for five minutes and the crude weight was obtained (0.471 g, 0.65 mmol) and acetone (9.4 mL) was added and warmed until the solid dissolved. The solution was cooled to room temperature for 5 minutes and then cooled in an ice bath for 15 minutes. The solid product was filtered via suction filtration and washed with cold acetone. After filtration and drying the crystals were collected, weighed (0.189 g, 0.261 mmol) and the melting point range (49-51 °C) of the product was obtained.

            A sample from the product (0.59 g, 0.816 mmol) was added to a new round boiling flask with 6 M NaOH (2 mL, 50 mmol) and 95% ethanol (2 mL, 43.41 mmol). The solution was brought to a boil and refluxed for 45 minutes. During this time, the remaining product (0.130 g, 0.18 mmol) was dissolved in boiling acetone (1 mL), cooled to room temperature for 10 minutes, cooled in an ice bath for 10 minutes and recrystallized a second time. The weight of the second recrystallization (.061 g, 0.084 mmol) and the melting point range (51-53°C) was observed. After the 45- minute hydrolysis, the flask was cooled to room temperature and the solution was poured into a 50 mL beaker containing water (8 mL, 444.44 mmol). HCl (2 mL, 65.38) was added dropwise to the beaker. The beaker was then cooled on ice for ten minutes with stirring and then filter via suction filtration. The product was dried overnight then the weight (0.077 g, 14.7%) and melting point (52-53 °C) were measured.

Discussion:

Crude trimyristin was extracted from nutmeg (1.010 g, 2.29 mmol) and recrystallized using acetone. Following the first recrystallization, majority of the sample underwent hydrolysis and acidification to form myristic acid. The remainder of the sample was recrystallized a second time. After the original extraction from nutmeg the crude trimyristin was recovered (0.471 g, 46.63%). This low yield makes sense because nutmeg is not composed solely of trimyristin. This trimyristin (0.471, 0.65 mmol) was then recrystallization and recovered (0.189 g, 18.71%). A low yield after recrystallization is common because impurities are ridden from the starting sample. However this very low percent recovery could be due to the left over crystals that remained in the flask after transfer to the suction filtration. Some crystals were also not able to be scraped off the side of the funnel from the suction filtration. The melting point of the trimyristin after the first recrystallization was 49-51°C. The true melting point of trimyristin is 56-57°C so the low recorded melting point range indicates the sample was not yet pure. A sample of the trimyristin product (0.130 g, 0.18) was recrystallized a second time (0.061 g, 46.92%). This percent yield makes sense because the sample had more impurities needed to be filtered out of the product. The melting point of the trimyristin after the second recrystallization was 51-53 °C. This increased melting point range indicated there were less impurities left in the product then the first because compounds melt at lower temperatures when they contain contaminants. However, even after the second recrystallization the sample is still not considered pure as it is still significantly lower than the true range of 56-57 °C. The main product of the trimyristin (0.059 g, 0.816 mmol) underwent hydrolysis and acidification to form the target product of myristic acid (0.077 g, 14.7%) The low percent yield is due to the loss of product during hydrolysis. The solution was too close to the heat source causing it to overheat and it went up the distillation column sticking to the sides. A rinse with 95% ethanol was done but not all of the product was removed from the insides of the column. The melting point range of this target sample was 52-53 °C. This melting point range confirmed the product identity because the melting point of myristic acid is actually 54.5 °C. The target product was not 100% pure because the measure melting point range was a few degrees lower than the true melting point range. However the accuracy of the thermometer is within 2 °C which allows the measured result to be a reliable confirmation that the final product was the targeted myristic acid.

Orgo discussion

Submitted by kmydosh on Fri, 11/17/2017 - 11:28

In this lab trimyristin was synthesized from nutmeg and myristic acid was synthesized from trimyristin. Trimyristin was recrystallized twice to obtain as pure of a sample as possible. Myristic acid was obtained by hydrolysis. The final product was obtained by suction filtration. The product was weighed and its purity assessed by melting point. The product was identified to be trimyristin which after its 2nd recrystallization had a melting point of 56° C. The melting point of myristic acid was found to be 54° C. The percent yield for the first recrystallization of trimyristin was 18%.  In future experiments extra time should be allowed for the cooling of the flask to room temperature so that as many crystals can form as possible. After the 2nd recrystallization of trimyristin the percent yield was 73%.  The final melting points of 56° C for trimyristin and 54° C for myristic acid confirms the identity of these products.  

co2

Submitted by dalon on Fri, 11/17/2017 - 10:59

Low levels of CO2 result in constricted arteries are caused by constriction by the smooth muscles in order for the oxygen concentrations to decrease and the carbon dioxide concentrations to increase. Thus, the transportation of oxygen rich blood is restricted because the main transportation of the oxygenated blood from the heart to the rest of the body, the arteries, is restricted via vasoconstriction. If not enough blood reaches the brain, a common symptom is often dizziness, which would be explained by the restricted arteries.

vitamin C edit

Submitted by dalon on Fri, 11/17/2017 - 10:58

This is due to the fact that in order for the vitamin C to be reabsorbed into the plasma, it must be actively transported out of the tubule. These carrier proteins or pumps can become saturated, at which point they are carrying the maximum amount of vitamin C the transporters can, and the rest will be excreted because it has surpassed the renal threshold, which is the concentration of solute that appears in the plasma when the transport maximum is reached. Thus, if a person takes 1000-mg of vitamin C once, it is much likely to oversaturate the transporters and thus be urinated out; however, with 2 500-mg doses, it is more likely to be reabsorbed.

Ecology Assignment

Submitted by jgcahoon on Fri, 11/17/2017 - 10:12

Part A

            I do not expect to observe the relationship between regional and local species richness in nature because the slope of the line is greater than 1, which is virtually impossible to achieve in nature. The slope of this line is greater than one because there are a greater amount of local species richness than regional species richness. This is impossible in nature because the spatial area of a region is larger than that of a local area.

Part B

            Based on this study, I believe that regional processes are the dominant driver of this pattern displayed in the graph. My first reason for this is the fact that the slope is slightly below 1, but does not level off (i.e. plateau) as regional species richness increases. Also, the local richness values are lower than regional richness values, but still increase with them proportionally in Study area 1, which is common of a regional process being the dominant driver in an area.

Part C

            Based on the equilibrium theory of island biogeography, I believe that the regional species richness on the mainland will affect how many species are predicted to be found on other islands. This theory talks about how immigration and extinction can affect the number of species on the smaller islands scattered around the mainland. Over time, an equilibrium is said to be made between these two rates, which will affect how many species are on other islands. 

Abstract for yeast (perf)

Submitted by daniellam on Fri, 11/17/2017 - 01:54

There are two ADE genes (ADE1 and ADE2) in yeast that must both be functional for them to produce adenine properly. When a haploid with a mutation in ADE1 mates with a haploid with a mutation in ADE2, the two functional halves of the ADE genes complement each other and form a diploid. Complementation can be useful for identifying the ADE mutation of unknown yeast strains. The simplicity of complementation in yeast exemplify a complex mechanism, in which two alleles with different functional parts can complement each other to form an important phenotype. The identification of the unknown mutants came out to be: MA1 is an ADE1 mutant, MA2 is an ADE1 and ADE2 mutant, MB2 and MB4 are ADE2 mutants. These experiments used yeast as a simple model to show the mechanisms of complementation which are complex and an important part of acquiring phenotypes.

Abstract for yeast

Submitted by daniellam on Fri, 11/17/2017 - 01:39

There are two ADE genes (ADE1 and ADE2) in yeast that must both be functional for them to produce adenine properly. When a haploid with a mutation in ADE1 fuses with a haploid with a mutation in ADE2, the two working halves complement each other and form a diploid with both working ADE genes. Complementation can be useful for identifying the ADE mutation of unknown yeast strains. The simple complementation in yeast exemplify a complex mechanism in which two alleles with different functional parts can complement each other to form an important phenotype. MA1 is an ADE1 mutant, MA2 is an ADE1 and ADE2 mutant, MB2 and MB4 are ADE2 mutants. These experiments used yeast as a simple model to show the mechanisms of complementation which are complex and an important part of acquiring phenotypes.

Anguilla rostrata

Submitted by msgordon on Thu, 11/16/2017 - 23:18

Adult members of Anguilla rostrata  spawn in the Sargasso Sea, start out as eggs/pre-leptocephalus larva. They eventually transform into leptocephalus larva and migrate passively on theFlorida and Gulf Stream currents. Next stage is as a glass eel - unpigmented/early onset of pigmentation. Actively migrate on continental shelf and coastal rivers. Begin feeding. Next stage is an elver - 7-8 cm in length, fully pigmented, actively migrate upriver in deep waters. Yellow eel, > 30cm total length, active feeding and growth, intermittent migration bc of weather/water conditions, territorial and nocturnal. Last stage is silver eel, begins down river spawning migration, nocturnal, stops feeding at start of emigration to Sargasso Sea. Glass eels are highly sought after in sushi

Lab 1 Discussion Perfect paragraph

Submitted by briangriffin on Thu, 11/16/2017 - 20:57

            In this lab we extracted and purified DNA using the methods explained earlier. The extractions were successful in that the DNA was removed from the tissue and cells of Arabidopsis and isolated from the other macromolecules in the leaves. This was evident by the pellet at the bottom of our centrifuge tube. This pellet then dissolved in T10E1  which means that the pellet was in fact made of nucleic acids. My pellet did not fully dissolve in the T10E1 with the specified amount, I added extra T10E1 to finish dissolving the pellet. The pellet not fully dissolving could have been due to the fact that I had too high of a concentration of nucleic acids for the original 50 µL of T10E1 to dissolve, so with a better ratio of T10E1 to nucleic acids, the pellet was able to dissolve fully. 

Multiple Alignment analysis

Submitted by briangriffin on Thu, 11/16/2017 - 20:50
The multiple alignment allows for you to align multiple sequences at once, while the pairwise align only can align two sequences at one time.The sequence "DFLDSGLENFRAALEKN" that is unique to humans is probably an insertion in the homo sapien lineage after the divergence from chimps. This is probable because everything from fish to chimps do not contain this fragment in the foxp2 gene so its likely that this one lineage has an insertion rather than all the other lineages having a deletion. Also I know that foxp2 is believed to be involved with the evolution of language in humans so it makes more for this unique fragment to be unique in humans. 

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