Throughout the evolution of humans, we moved out of our environment of evolutioary adaptiveness and into a new, novel environment. One major shift humans made was in their diet conposition and as a result, humans have become vulnerable to different diseases and conditions we were not vulnerable to before. For humans, the major physiological change change was an increased brain size occurred during the Paleolithic Era which lasted for 2 million years. Because a larger energy input was needed to sustain the growth of a large brain, our diet played a key role in giving us the energy and nutrients that enabled these changes. The human diet is something that has changed considerably from the environment of evolutionary adaptiveness and we are now facing a slew of health consequences as a result. One of major heath consequences is obesity, which often leads to the other conditions are at risk of developing. There are two aspects of the the human diet which varies from the environment of evolutionary adaptiveness: the eating patterns of humans and the composition of the diet. With both these factors different in the novel environment of humans, humans are now vulnerable to a variety of detrimental health conditions.
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Nicotine has a largely negative health connotation due to its prevalence in cigarettes and vaporizer products. Nicotene itself was not considered to be the most dangerous ingredient in these products. The chemical and flavorings in vaporizers as well as the tar created from combustion in cigarettes are considered the most toxic to human health. However, Duncan Et Al. have demonstrated that nicotine consumption in rodents results in diabetes-like symptoms, including failure to regulate blood glucose levels1. This discovery comes at a time of social panic over nicotine-based products, vaporizers in particular, and is sure to impact future conversations.
(1) Habenular TCF7L2 links nicotine addiction to diabetes. Nature [Internet]. 2019 ;574(7778):372 - 377. Available from: http://www.nature.com/articles/s41586-019-1653-xhttp://www.nature.com/articles/s41586-019-1653-x.pdfhttp://www.nature.com/articles/s41586-019-1653-x.pdfhttp://www.nature.com/articles/s41586-019-1653-x
Throughout the evolution of humans, we have consistently changed to a novel environment which no longer matches our environment of evolutionary adaptiveness. As a result, humans have become vulnerable to different conditions we were not vulnerable to before. For humans, a majority of physiological changes including increased brain size occurred during the Paleolithic Era which lasted for 2 million years (Easton 67). Because a majority of the evolutionary traits which defines us as a species occurred during this time, our diet played a key role in giving us the energy and nutrients that enabled these changes. The human diet is something that has changed considerably from the environment of evolutionary adaptiveness and we are now facing a slew of health consequences as a result. One of major heath consequences is obesity, which often leads to the other conditions are at risk of developing. There are two aspects of the the human diet which varies from the environment of evolutionary adaptiveness: the eating patterns of humans and the composition of the diet. With both these factors different in the novel environment of humans, humans are now vulnerable to a variety of detrimental health conditions.
Our bodies require the formation of proteins at all times - whether it is for cellular function or intercellular function or it is needed for an organ in general. All systems in our body need protein to function. The process involves two parts to it: transcription and translation. Transcription is the process by which the DNA transfers its information to an mRNA, while translation is the process by which mRNA helps to create the protein. During transcription, DNA unwinds and mRNA nucleotides (cytosine, guanine, adenine and uracil) align along the sense strand according to the base-pairing rule. Once the strand forms, it is transported out to the ribosome subunit where translation takes place. There are tRNA nucleotides floating around in the cytoplasm. They bind to amino acids and transport them to the same ribosomal subunit where the mRNA is waiting to br translated. The tRNA align the corresponding amino acids and form a polypeptide chain. Then the tRNA leaves and the polypeptide chain is either transported within the cell or out of the cell via exocytosis. Most of the time the chain is transported to the Golgi body for modification. Once done, they are packaged into vesicles and transported out via exocytosis.
The flu shot is often something that is not a priority. The flu shot changes every year to keep up with the varying proteins on the virus. The vaccine is important for the recipient's protection against the flu, as well as everyone surrounding them. Certain individuals are vulnerable to disease, they are the elderly, infants, those recieving chemo-therapy, and individuals with an autoimmune disease. Individuals who are immunocompromised cannot get vaccines, vaccines should be administed several weeks before the individual becomes immunocompromised (if that is possible, such as several weeks before chemo-therapy). These immunocompromised individuals can be protected through herd immunity; when the majority of a population is vaccinated, the virus has a hard time infecting individuals. Therefore everyone should keep up with their flu vaccines to prevent contraction of the virus for themselves, as well as immunocompromised individuals who cannot recieve the vaccine and rely on others for protection.
As global temperatures rise, phenological changes have occurred causing flowering times of plant species to occur earlier than previously recorded in the past (Bartomeus, Ascher, Wagner, Danforth, Colla, Kornbluth, Winfree, 2011). The New England Cranberry, Vaccinium macrocarpon, is not an exception to this phenomena. Cranberries act similar to wild plants in the case of the phenology differing in warmer temperatures. Since cranberries have been an important part of New England culture, cultivators have kept records of cranberry growth and production. Cranberry cultivators have been spraying fungicide on the crop when 10% of the flowers have bloomed. This quantifies timing of cranberry flowering over the years. The earlier flowering times of cranberries affects not only cultivators, but other species that interact closely with the plant. Cranberry shoots and leaves are an important food resource for the bog copper butterfly, Lycaena epixanthe. As global temperatures rise, the concern for earlier flowering times affecting both human cultivation and other species interactions continues to grow.
In Fall 2019, as part of the Junior Writing Class at the University of Massachusetts Amherst, I conducted a project to produce careful writing such that an exact replica of the obtained results can be reproduced. The Methods project is influenced by the idea that scientists must be able to carry out an experiment and reproduce the exact results if they were to also perform the experiment. The goal of the Methods project is to learn how to create a multi-panel scientific figure and ultimately compare an image with someone else’s replicate of your image, who has followed your outlined methods. The topic of the experiment was phytophagy or the eating of plants. The subject that was chosen for this experiment was a leaf with a hole in it. This was inspired by the simplicity of the subject.
DNA replication is an important biological process that acts as a basis for cell growth and division. When somatic cell divides, the DNA must also replicate itself so that each daughter cell will contain identical DNA transcripts. This process begins at sections of the DNA called the origin of replication. These origins of replication tend to contain AT repeats due to the fact that Adenine and Thymine have a weaker bond making it easier for those two nucleotide to seperate. Helicase will separate the base pairs and establish the replication fork. Initiator proteins will bind to the origin of replication and recruit essential proteins for replication. DNA polymerase will be recruited by the initiator proteins like primase and begin elongation in the 3' direction. Following initiation, the DNA will elongate in a 5' to 3' direction due to the free hydroxyl group. The opposite strand, or lagging strand, must be replicated in fragments because DNA must be replicated 5' to 3'. These fragments are called Okazaki fragments. Since DNA replication is initiated at many parts in the genome, it will be terminated a various points as well. Termination will be a result of a blocked replication fork.
A concussion is defined by Meehan et al. as a blow to the head, neck or face that causes short term neurological deficits without structural changes in the brain as seen by neuroimaging. Concussions are a very serious medical injury that can lead to long term brain damage that impacts memory, behavior, and mental ability. Why is it then that so many young athletes often go undiagnosed with serious injuries? Meehan et al. reported that less than half of high school students who sustained concussions during a football game would report it to medical staff. In college students, they were unlikely to report any injury, but when they did they often called their concussion a minor head injury, detracting from the seriousness of what they sustained. It was found that up to 30% of athletes showing symptoms from injuries known to cause concussions went undiagnosed. The percent of students in contact sports that were observed to have a head injury and resulting concussion symptoms is consistently lower than the percent of students confirmed to have concussions by medical diagnosis. This is a great pitfall in reducing the harm done to young athletes especially during adolescent years when the brain's formative functions can be greatly impacted by such a disturbance (Meehan).
Meehan, William P 3rd et al. “The prevalence of undiagnosed concussions in athletes.” Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine vol. 23,5 (2013): 339-42. doi:10.1097/JSM.0b013e318291d3b3
The meristems are the stem cell niches in plants, regions of the plant that contain undifferentiated stem cells. These cells are classified as stem cells because they fit the criteria of being self-renewing, undifferentiated, totipotent or pluripotent, and are found in a specialised area called a niche. Both plants and animals have stem cells that can generate new cells. However, plants not only have the ability to regrow entire organs from their stem cells, but can also regenerate themselves from any one of their cells. That is, if the organism were to be dealt cataclysmic damage - such as a tree being cut down to its base - it would be able to regenerate completely. This is due to the fact that all of a plant’s cells, unlike an animal’s cells, are totipotent. When the plant is wounded, the differentiated cells around the wound will dedifferentiate into a group of cells - called a callus - that can grow into any new organ the plant needs. Depending on the concentrations of hormones the callus is exposed to, it will differentiate into different organs. Higher concentrations of auxin lead to more root formation and higher concentrations of cytokinin lead to more shoot formation. From this callus can be grown new organs or even an entirely new plant. Although it is true that all plant cells can be totipotent and self-renewing, they do not fulfill the two other criteria that would make them stem cells, being undifferentiated and being in a niche. Thus, not all plant cells are stem cells, only the undifferentiated cells in the meristems count as stem cells.