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The amount of a protein that is synthesized depends on the amount of the corresponding mRNA that is available for translation. The amount of available mRNA, in turn, depends on both the rate of mRNA synthesis and the rate of mRNA degradation. Eukaryotic mRNAs are generally more stable than bacterial mRNAs, which typically last only a few minutes before being degraded. Nonetheless, there is great variation in the stability of eukaryotic mRNAs: some persist for only a few minutes, whereas others last for hours, days, or even months. These variations can produce large differences in the amount of protein that is synthesized. Cellular RNA is degraded by ribonucleases, enzymes that specifically break down RNA. Most eukaryotic cells contain 10 or more types of ribonucleases, and there are several different pathways of mRNA degradation. In one pathway, the 5′ cap is first removed, followed by 5′→3′ removal of nucleotides. A second pathway begins at the 3′ end of the mRNA and removes nucleotides in the 3′→5′ direction. In a third pathway, the mRNA is cleaved at internal sites.

Genome editing (or gene editing) is a type of genetic engineering that involves modifying a living organism’s genome. Specific regions of the genome are deliberately targeted and DNA sequences are inserted, deleted, or otherwise modified to change the sequence at that location and alter gene function, either by preventing or enabling expression, or by changing how the gene is expressed (“Genome editing in brief: what, why and how?”, n.d.). Genetic disorders can affect both somatic (body) cells and germline cells (cells involved in reproduction, such as sperm and eggs). While genetic mutations in the DNA of somatic cells only affect the individual and cannot be inherited, changes in the germline DNA are heritable and can affect future offspring (Ormond et al. 2017). Genetic disorders can only be “cured” by targeting them at the genomic level, which these new advances in molecular and genetic technology have made possible. There are, however, concerns about its viability, ethics, and long- and short-term consequences, especially surrounding the topic of germline editing. Both somatic and germline cells can be edited, and while any changes made to the DNA of an individual's somatic cells will only affect that individual, changes made to their germline DNA could be inherited by their future children. The technology at present cannot guarantee that “unintended modifications created through an editing procedure would not result in a devastating long-term outcome such as cancer or adverse developmental effects if one were to modify a zygote” (Kohn, Porteus & Scharenberg, 2016), which has lead to mixed scientific and public opinions about its use.

Modern gene editing techniques have heightened as researchers continue to investigate the regulation, safety and effects of genetic engineering. Although these gene editing tools have the potential to treat various diseases, there is not enough information to determine the overall impact and significance of genetic engineering and specifically in GM foods.

Genetically modified (GM) foods are foods that are bioengineered to allow for changes to be introduced into their DNA. GMOs are a controversial issue as many of these foods are ones that are consumed daily. Researchers detect that US consumers are optimistic about possible benefits of GM foods, but are also concerned with their associated health, safety and environmentally harmful consequences (Costa-Font, Gil, & Traill, 2008). In this study, we explored the ethical beliefs and opinions of 40 UMass students in respect to GM foods. Analyzing these students responses will allow us to obtain a general understanding of college age students virtue of genetic engineering and specifically GM foods.

Overtime birds have become more specialized in the way they eat their food. Typically birds swallow their prey whole, whether the bird is consuming seeds, fruits, or insects whole. However raptors are a category of bird that cannot do this. Raptors hunt larger prey than other types of birds, so their sharp, hooked beaks allow them to pierce prey, tug away skin, pluck out feathers, tear meat into smaller-sized chunks that are easier to swallow. Insectivores use their slender, tweezer-like beaks enable them to catch insects midair, pick insects off leaves, or probe between small crevices of tree bark, or for drilling holes into wood. This contrasts with seed-eating birds have short, thick, and strong beaks equipped for cracking open hardy seeds. The size of the beak can indicate the type of seed or nut the bird is adapted to eat. The variation in beak size within the raptors, seed-eaters, and insectivores observed across grasslands, woodlands, and marsh habitats can be explained by the specialized diets in different habitat types.

When marine mammals dive into deep, high pressurized waters, they experience an increase in dissolved nitrogen gas in their bloodstreams. The dissolved gas poses a threat because if the divers ascend too fast, they experience a phenomenon known as the “bends,” whereby gas bubbles form inside the body and increase the risk of contracting decompression sickness. Fortunately, marine mammals have a special lung architecture that creates two different pulmonary regions to combat high-pressure depths. They have a compressible chest that limits the amount of nitrogen gas that can be absorbed. The authors of the review article suggest that the physiology of diving mammals is poorly understood, and that there are other cardiorespiratory mechanisms that provide a better explanation for their ability to dive deeply. The results of the paper showed that many marine mammals can withstand high levels of nitrogen gas that would normally cause decompression sickness 50% of the time. The authors also hypothesized that parasympathetic stimulation helps limit lung perfusion, which is a necessary for diving to great depths. They propose that high amounts of stress can interfere with this process and might explain the failure of a normal dive response. Overall, these findings are significant because they offer a new perspective on the physiological and respiratory adaptations that enable cetaceans to dive at great depths. 

In the unknown lab, we started by gram-staining our unknown organism. This is a way of testing for the presence of a thick polysaccharide wall. Gram positive organisms have this thick wall, while gram negative organisms do not. To gram stain, first 4-5 drops of crystal violet are added onto the organism. Then after 60 seconds it is washed off with sterile water, and 4-5 drops of iodine is added for 60 seconds. Then hydrogen peroxide is added and left on for 10 seconds. Then 4-5 drops of safran is added for 60 seconds. Once that is done, the organism is observed under a microscope. The gram positive organisms appear purple, and the gram negative organisms appear pink. Gram negative organisms consist of non-fermenters and enteric bacteria. Gram positive organisms consist of staphococci and strepococci. Oxidase tests are done on gram negative bacteria to distunguish between non-fermenters and enteric bacteria. Positive tests appear for non-fermenters. Catalase tests are done on gram positive tests to distinguisg between staphococci and strepococci. Positive tests appear for staphococci. 

The extent of harm each of the invasive species had on the environment and economy was assessed. To do so, research was conducted on each herb’s effect on specific criteria regarded as highest concern to least concern granted a multiplier, with a range from 1X for least concern to 2X for most concern. The criteria were split into parameters that defined the plants’ effect in that category as high (3 points), moderate (2 points), or low (1 point) threat. The summation of points was used to quantify the threat of each herb.

A novel GDSL-type esterase, SFAR4 was found in Arabidopsis thaliana. In this study, knockout mutants and overexpression lines were established. The absence and overexpression of the SFAR4 gene had no effect on germination rate when compared with the wild-types. However, in the presence of glucose, the lines with overexpressed SFAR4 had significantly higher germination rates than wild-type and knockout mutants. In contrast, the presence of mannitol did not affect germination rates. This finding suggests that perhaps SFAR4, a GDSL-type esterase plays a role in glucose susceptibility and glucose metabolic pathway regulation in germinating seeds. In this same study, the expression of fatty acid metabolic genes are shown to be differential in SFAR4 overexpression lines and knockout mutants. SFAR4 overexpression lines show increases levels of metabolism pathway components while knockout mutant lines are accompanied by lower levels of fatty acid metabolism gene expression. This indicates that SFAR4 plays a role in fatty acid metabolism.

Researchers found a connection between the hormone noradrenaline and perception of images. It was found that people with higher levels of noradrenaline in their systems were able to discriminate low quality images better. What the researchers attempted to figure out was whether if noradrenaline and an effect on sensory perception and if noradrenaline improved perception of images. Noradrenaline plays a role in the late processing of the cerebral cortex. Therefore, it would determine whether the image would be brought back into the person’s memory. Typically, noradrenaline is expressed during arousal but there are more functions to the neurotransmitter that was found.