Writing in Biology - Section 1

Alzheimer's disease is a very impactful disease that has been extensively researched because of its dramatic effects on those with it and its high virulancy. Even then, research is ongoing and continuously discovering more. The beta amyloid accumulation in neurons of alzheimers patients shows to cause neurological dysfunctions that may be attributed to the disease, although the symptoms may also be due to mitochondrial errors. the function of the mitochondria relies heavily on its interactions with other organelles in the cell. Mitochondria–ER contacts are used for mitochondria and ER to share membrane bound proteins. An experiment with dysfunctional amyloid betas was done and it found swelling in the eR and mitochondria issues in the test subjects. This mechanism could be driving some of the Alzheimer's symptoms from over accumulation or not working amyloids.

The structure and formation of the ER outlines how the ER assists in protein and lipid synthesis among other biological processes. There are two types of ER, as seen in Figure 2, the rough ER and the smooth ER. The name of the rough ER originates from the fact that ribosomes spot the outer membrane. In contrast, the outer membrane of the smooth ER contains no ribosomes. Depending on the type of cell, the ratio of smooth to rough ER will vary drastically (“The Endoplasmic Reticulum”). Both types of ER, however, have a similar structure of a large, continuous membrane that folds to create intramembrane spaces of different sizes. This intramembrane space is known as the cisternal space and connections exist between the cisternal spaces themselves in addition to the nucleus. The whole organelle is supported by the cytoskeleton of the cell which allows the ER to maintain its structure (English).

Among all bioindicators, lichens have been identified as a useful plant to monitor the level of pollution in the environment. The purpose of this study is to observe the species diversity of lichens in different settings and use it as an indicator for air pollution. They can be used in two ways to monitor air pollution: 1) grouping the species of lichens present in a specific area 2) measuring the morphological changes or the accumulation of pollutants in the lichens. Ultimately, lichens are very significant to our everyday world as they provide a means to convert carbon dioxide in the atmosphere through photosynthess into oxygen, which humans need to survive. For this study, our specific aim is to compare the air pollution when lichens are present among different levels of urbanization.  The first method will be applied to correlate the diversity of lichens to the air quality. It is imperative to pay close attention to the environment now more than ever, and so any step to detect and control a problem must be taken to find and implement a solution. 

    In eukaryotic cells, the smooth ER is a major site where membrane lipids are synthesized (Cooper). Membrane lipids must be synthesized on the cytosolic side of the ER membrane, or outside of the ER membrane (Cooper). After the lipids are synthesized they follow a similar pathway to proteins where vesicles transport the lipids to their final destinations. The smooth ER more specifically synthesizes three important membrane lipids: ceramide, cholesterol, and glycerol phospholipids (Cooper). Ceramide undergoes further processing in the Golgi to become sphingomyelin. Therefore the smooth ER produces a variety of lipids that either act as precursors that require more processing or are final products (Cooper).

The main function of the rough ER is to synthesize, process, and transport proteins. This biological process begins in the cytosol where a ribosome initiates the translation of an mRNA strand. The ribosome may translate a short signal sequence on N-terminus that marks the polypeptide as destined for the ER. A signal recognition particle, or SRP, will recognize this sequence and bind to the polypeptide (“Molecular Biology”). Figure 3 reflects the process of translation in two different scenarios: when a polypeptide expresses an ER signal sequence or no signal sequence. With the SRP guiding, the complex is then localized to a translocon on the rough ER membrane. As the ribosome creates a protein strand based off of the mRNA transcript, the channel protein allows the polypeptide chain to enter the ER lumen where protein folding commences. This process where the still synthesizing polypeptide enters the ER is known as co-translation (Cooper). Within the ER lumen are a variety of chaperone proteins that help fold polypeptides. These chaperone proteins contain an ER retention sequence so that they remain within the ER (Cooper). Other proteins that have entered the ER to be processed contain only a temporary ER signal sequence and exhibit another signal sequences for a different cellular location. In that case, proteins will be packaged into a vesicle, a membrane bound sack, that buds off of the ER. This vesicle travels along microtubules, the “backbones” of the cell, until it fuses with the membrane of the Golgi (“Transport from the ER”). The Golgi acts as the final step to process and transport the proteins to their ultimate location in the cell. Figure 4 reflects the general pathway that proteins follow depending on the individual protein’s signal sequence. 

The flu is a nucence, it seems like everyone gets it so why bother getting the flu shot? The flu shot is often neglected, according to the Centers for Disease Control, only 37% of Americans recieved their flu shot in the 2016-2017 season.  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.

The structure and formation of the ER outlines how the ER assists in protein and lipid synthesis among other biological processes. There are two types of ER, as seen in Figure 2, the rough ER and the smooth ER. The name of the rough ER originates from the fact that ribosomes spot the outer membrane. In contrast, the outer membrane of the smooth ER contains no ribosomes. Depending on the type of cell, the ratio of smooth to rough ER will vary drastically (“The Endoplasmic Reticulum”). Both types of ER, however, have a similar structure of a large, continuous membrane that folds to create intramembrane spaces of different sizes. This intramembrane space is known as the cisternal space and connections exist between the cisternal spaces themselves in addition to the nucleus. The whole organelle is supported by the cytoskeleton of the cell which allows the ER to maintain its structure (English).

The other day in my genetics class, we were talking about cloning and the idea of cloning your own pets such as dogs and cats came up. Although I don't have neither a cat or dog, I still would be againt cloning one of my pets. Aside from the ridiculous idea of cloning your pet, the price to do so was even more outrageous. It costs $50,000 to clone your dog and $25,000 to clone your cat. We took a class poll to see what the majority of people would answer to whether they would their pet, and the majority of the class voted no. This did not surprise me at all since this was never topic of discussion that has been brought up with anyone that I've ever talked to. I guess a valid reason to clone your pet is if it dies suddenly to a traggic accident; but even then, is that what's best to do?

Studies have been done where researchers alter thyroid hormone levels by treating adult rats with T4, the same drug we will treat our zebrafish with. In these studies, they have found that neural stem cell proliferation decreases in T4 treated rats. The differences in our experiment is that we are using zebrafish as a model organism, the zebrafish are 5 days post fertilization, and the dosage of TL4 that we are using can be different since we do not know how much was used in the study on adult rats.