In this study we propose to investigate the effects of urbanization on the density and diversity of periphyton in the Sylvan Stream. Periphyton are indicators of aquatic environmental conditions and serve as the primary producers in freshwater food webs. In this experiment, there will be 8 teams that will sample different sites along the Sylvan Stream. The 8 sites of collection will span 800 m of the river starting 15 m from Sylvan Residential Area. Microscope slides will be used as a surface by which to collect periphyton over the course of two weeks. The collected slides will be analyzed by light microscope and compared. As a result of this experiment, we hope to provide insight about local effects of pollution radiating from a point of origin on nearby watershed.
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According to the paper, Copidosoma develops much differently than the Fruit fly. This is due to Copidosoma using regulatory development, which is the same mechanism by which vertebrates develop. This type of development is characterized by conditional specification resulting in tissues developing due to induction by neighboring tissues. One Copidosoma egg gives rise to thousands of embryos and the VASA protein defines the germ line cells of reproducing individuals. The ablation of one cell from a Copidosoma embryo (only if it is not the VASA containing cell) still results in formation of a complete larva. The Fruit fly, on the other hand, uses mosaic development characterized by syncytial specification resulting in reliance on maternal determinants to signal cell differentiation. The ablation of one cell from a fruit fly embryo at the two-cell stage would result in only half a larva.
With the rapid loss of domestic dogs, the sadness is palpable, and the purity of the golden retriever's spirit will mend the hearts of humanity. Their calm, fun-loving demeanor is a reminder to live in the present and enjoy the little things in life. Dogs have been a part of our lives for millennia, and have become deeply intertwined with the human identity. I promise that by saving the golden retriever, all dog breeds we knew and loved before will return with successive breeding. The golden retriever is a perfect example of the wonders of trait selection in dogs, and will serve to inspire the rebuilding of dog breeds all around the world with its beauty and charisma.
As a person whose life has been deeply enriched by dogs, I propose that golden retrievers are the most well-rounded dog breed to save with the vaccine. Today, golden retrievers remain one of the most popular dog breeds owned, and are well acclimated to a numerous amount of climates found around the world. The advancement of modern machinery has reduced the need for working dogs, and the needs of humanity have shifted to emotional support for various physical and mental health issues. There are many people struggling with debilitating issues that have shown great improvement with the introduction of a service animal. Golden retrievers are one of the most prevalent service animals, with an insatiable need to please and great adaptability.
A hydrolysis reaction using 6 M sodium hydroxide and concentrated hydrogen chloride was used to yield a final product of myristic acid at 75%. In the chemical equation of hydrolysis one molecule of trimyristin should yield 3 molecules of myristic acid. 58 mg of trimyristin was consumed in the reaction. The theoretical yield would be 55 mg of myristic acid and 41mg of product was collected. This gave a fairly high yield of myristic acid. Any of the losses seen in the experiment could be due to transfers or from not adding enough hydrogen chloride. The melting point of the product was found to be 52-54 °C, which indicates the result of a pure product due to the literature melting point being 54 °C.
Trimyristin was isolated from ground nutmeg seed using t-butyl methyl ether to yield 29% crude product. The crude trimyristin was recrystallized once to yield 40% of product and recrystallized a second time to yield 10% of pure product. The starting material, ground nutmeg seed, contains many more compounds than just trimyristin, which would explain why the yields appear to be of small value. As the purity of the product increased through successive recrystallizations, the amount of product obtained decreased as the mass of the impurities or other compounds were lost. Excessive heating could have caused some reactant to evaporate out of the distillation column, and the cotton fiber may have absorbed some of the solution when performing pressure filtration. The purity is represented in the melting points of the products. The first recrystallized product had a melting point of 48-50 °C, and the second recrystallized product had a melting point of 50-52 °C. Both of these ranges suggest that impurities were present because they are lower than the literature value melting point of trimyristin is 56-57 °C. However, after each successive recrystallization the melting point became closer to the accepted value for trimyristin indicating the removal of most impurities. The product is still assumed to be trimyristin.
The plates were run in a 9: 1 of CH2Cl2: ethanol, which is a moderately polar solvent. The starting material (benzoin) had an Rf value of 0.75 on both plates. The crude Rf (0.44) and recrystallized Rf (0.48) traveled less distance on the plate than benzoin indicating their increased polarity. Hydrobenzoin is less polar than benzoin because secondary alcohols are more polar than ketones. Sodium borohyhdride was selected as the reducing agent in this experiment instead of more explosive lithium aluminum hydride, and it is selective in reducing only aldehydes and ketones. Sodium borohydride was sufficient for fully reducing the benzoin, demonstrated by the lack of observed benzoin in both crude and recrystallized products.
The target product of hydrobenzoin was obtained thorugh a reduction reaction of benzoin using sodium borohydride as the reducer and resulted in a 55% yield. Recrystallization with acetone as a solvent was used to separate the hydrobenzoin product from remaining impurities. The presence of hydrobenzoin was confirmed from the thin layer chromatography performed.
The seemingly immortal cell line collected from unwitting donor Henrietta Lacks in 1951 has had innumerable implications in medical ethics and science. These ‘HeLa’ cells have gained a tremendous amount of fame without any question as to their origins. Billions of dollars and countless medications for previously untreatable diseases such as polio, leukemia, Parkinson’s, and influenza have been derived from the HeLa line, proving their significance. Henrietta Lacks, born in 1920, was a descendent of African American slaves and their white masters, and grew up in rural Roanoke, Virginia. Henrietta, like most of her family members, worked tirelessly as a tobacco farmer starting at an early age. Over the course of her marriage to David Lacks, Henrietta bore a total of five children, one of them only four and a half months before her diagnosis of cervical cancer at Johns Hopkins Hospital. This common diagnosis was treated with radium tube inserts and instructions for follow up visits. During one of these follow ups, two samples were taken from Henrietta’s cervix without her permission or knowledge and were studied extensively.
An organism that inhabits the deep ocean that has many adaptations for its extreme environment is the deep-sea angler, Melanocoetus johnson. Females are much larger than males and have a bioluminescent stalk between their eyes. They use this stalk to attract baitfish to a sharp set protruding teeth. The male deep-sea anglers are much smaller than the females and his main purpose is to locate a female. The males have highly sensitive nostrils they use to sniff out their mate in the complete darkness at 2.3km beneath the surface. One a female is located, the male angler attaches himself to the underside of the female with his teeth and remains there as a parasite. He feeds from the female until he is needed to fertilize eggs. These fish only have to mate once in their lives because the male becomes physically part of the female and will fertilize all of her future eggs.