Drafts

Genetically modified organisms (GMOs) have been very prevalent in recent years in the ongoing debate about what foods we should be eating and how different foods affect us. For a while I didn't really know what GMOs do or how they affect us, until last semester in my genetics class. My professor, Professor Loomis, told us how scientists have been able to modify the genomes of certain crops, like wheat. These genetic modifications have allowed the crops to survive being sprayed with pesticides. This is great for farmers because they can easily rid their crops of insects/pests while increasing their yield; however, this has detrimental effects on the populations who eat these crops. The pesticides get absorbed into the plant and the plant doesn't die, but the chemicals in these pesticides remain in the crop all the way until they are consumed, poisoning whoever consumes this product.  Professor Loomis then told us that this is a big reason why many people in the US have gluten insensitivities, or so they think. People with so called “gluten insensitivities” are just responding to the pesticides that are in their food, that have traveled from the wheat fields to their plate. She stated that people who have what they think are gluten insensitivities can go to Europe and eat the bread there just fine, because they’re not made with genetically modified wheat crop that has been sprayed down with pesticides. While this is still all I really know about GMOs, I think they could be potentially useful if implemented correctly. GMOs could help fulfill food needs of a steadily increasing world population. In their current state, GMOs need a lot of improvement before their use is practical and efficient (and doesn’t poison people), but many people recognize their potential, and are working towards better GMO solutions.

The legacy of Cicero that I knew about before reading his quick biography was that he was an excellent orator. That still seems true, but he was certainly more than that. It appears his oratory skills are what elevated him to the next level of his political career. I doubt he had any remarkable military experience because "he was spare and lean, and owing to a weakness of the stomach" (Plutarch, III). Therefore he must have relied strongly on his oratory and debating skills in order to prove himself to the people of Rome. I think it was especially interesting that he was a son of a knight, not a nobleman, which was rather unique for a consul. This must reflect how highly Rome though of Cicero because they did not care about his lineage when they chose him to run against Catiline. I also find it interesting that despite his drastic ruling to execute traitors, the Roman people still seemed to support him. In fact they "voted him the greatest honours ever conferred and called him the father of his country" (Plutarch, XXIII). I wonder if the Romans actually approved of the executions or just so vehemently supported Catiline that they bestowed him these honors regardless. 

The axon is a nerve fiber that transmits electrical signals also known as action potentials from one cell to another. The signals travel from one direction, and that is from the cell body out to the synapse of a postsynaptic cell. The axon itself is comprised of many things. This includes the cell body, its nucleus where genetic material is held, dendrites, terminal buttons, nodes of ranvier, and the myelin sheath. The axon is a long fiber which generates action potentials. When the cell reaches threshold, an action potential fires. This is an all or nothing response. Anything below the threshold will not fire an action potential. In the same token, action potentials cannot be stronger or larger, they simple fire at a higher frequency if threshold is reached continuously. 

There are a myriad of visual signals ranging from pigmentation to postural displays. Pigmentations are one of the ways animals can display colour. Melanin is a pigment that produces a range of colours from black to brown. Prairie warbler males deposit melanin in their wings to strengthen them, and females use these melanin stripes as an indication of the male’s health. Carotenoids are an orange pigment that animals acquire from plants. Pterins are a red pigment produced by lizards, such as in anoles’ dulaps. Porphyrins are pigments with multiple qualities. Firstly, in the visual spectrum, porphyrins produce browns, reds, and greens. Secondly, porphyrins under UV light produce a bright red colouration. Porphyrins are a good example of the fact that animals have their own way of perceiving the world, some can detect UV and so would see porphyrins differently than we do. Another way animals can produce colouration is through structure. Hummingbirds’ iridescent plumage is the result of refraction in their feathers. The microscopic structures in their feathers act as prisms that reflect only certain wavelengths of light, resulting in shiny, metallic colours. Blue jays don’t have blue pigment in their fathers, but have microscopic air bubbles that refract light to produce different shades of blue. Animals also produce visual signals through posture, gestures, displays, and facial expressions. Posture and gesture are different as posture involves the whole body whereas gestures only involve arms and hands. An example of a posture is dog bowing, where the front of the body is arched downwardly, the rear is raised, and the tail is wagging, which indicates the desire to play. Gestures are much more present in animals with hands, such as primates. Chimpanzees for example have 66 unique gestures without idiosyncratic use, that is, they conserve the same function for all chimpanzees. In addition, some of these seem to be evolutionarily conserved, as other primates like orangutans and gorillas share 24 of these gestures with chimpanzees. Displays are present throughout the animal kingdom. The penguin mating display in Gebes involves the fanning of head feathers and the presentation of a piece of aquatic vegetation. Facial expressions have been well-studied in humans and it has been shown that there are 7 pan-culturally recognised facial expressions. These expressions are: anger, joy, fear, sadness, surprise, disgust, and contempt. Though, contempt is an exception in that it isn’t present in all cultures.

Major crops cultivated today diversed from many different regions across the world. From Southern Mexico and Middle America came maize. Tomatos diversified from South American countries such as Bolivia, Peru, and Southern Chile. Peas and olives came from the Mediterranean Sea and other coastal regions. From the Middle East came the pear. The center of diversity for hemp and carrots were Central Asia countries such as Afghanistan. Rice and orange diversified from India. The main crops to diversify from China were rice and soybean. It is very interesting to know that there were many centers of diversity for crops to diversify from.

In the agriculture industry, only a handful of companies own the rights of a few strains of crops. This monopoly over the agriculture space results in abusive behavior from companies, threatening lawsuits against farmers and engaging in unethical conduct. However, with the advent of cheap alternatives to gene editing, this monopolization could soon come to an end. The expensive process of utilizing agrobacterium-mediated transformation of plants is being replaced by the cheaper, more percise method of CRISPR editing. Not only is this a cheaper and more accurate alternative, but CRISPR modification of crops will not necessarily require the GMO label on the final product-a label that many consumers shy away from. Because of this, small agriculture companies and startups, such as Inari in Boston, will soon be able to compete with the likes of Bayer, and make edited crops a more competitive business.

A monoculture is the farming of one crop in a single area. The advantages of this process are three-fold. First, a single type of crop allows for the mechanization of the various farming process that goes into planting and harvesting foods. Heavy machinery replaces the hands of people and therefore increases the amount of possible cultivated food and the speed at which it occurs. We, as a species, prefer this method of farming because it allows us to feed the large and demanding global population we have today. Without it, we could not sustain the seven and a half billion people we have today. Second, uniformity in crops means that care of these large monocultures is kept low. This means that farmers don't need to have multiple different sprays and chemicals needed to combat disease and pests. A single product can be used for every need. Also having single crops in one field prevents the outcrossing of two species to create hybrids or new species. Third, monocultures can be cultivated by heavy machinery in large single batches and don't require separation by hand. The later processing of the food can also be industrialized from both the amount of volume brought in and the lack of contamination from another crop.

There are two key disadvantages to monocultures. First, a monoculture has increased susceptibility to disease. In a field of a single plant, the likelihood of a disease event where the entirety of a crop becomes wiped out is fairly high. A single new pathogen unknown to the plant's defense systems could infect one and eventually all the plants. Unfortunately, plants do not have an adaptive immune system so when a new pathogen is present they cannot defend themselves. If every plant in a field were to be identical and susceptible to a disease, then they all die. Second, a monoculture loses landrace diversity. Landrace diversity is the diversity of crops grown in one area. Similar to disease susceptibility, a decrease in heterozygosity prevents new beneficial mutations or hybrids from developing. A loss in ecological diversity can severely impact an ecosystem that may rely on disappearing species.

Modern day plants come from many lineages which trace back to a very important event: endosymbiosis. Endosymbiosis is the engulfing of an organism by something else and thus lives inside the other. In modern day plants, this began with cyanobacteria. Cyanobacteria is a blue-green algae that is photosynthetic. In the earliest forms of cyanobacteria, they did not release O2 into the atmosphere. But later down the line they began oxidizing. For plants to evolve, the primary event of endosymbiosis occurred. A eukaryotic cell engulfed the cyanobacteria and degenerated into a chloroplast. After this event, a second endosymbiosis event occurred that diverged into red and green algae and thus their divergents. Without these events of endosymbiosis, the ancestors of plants wouldn’t have been able to evolve into what they are today. 

An elaborate representation of static electricity can be demonstrated through the use of a Van de Graaf. Structurally, a Van de Graaf has base with a dial to turn it on and increase/decrease the voltage. It is plugged to a power outlet through the base. Emerging from the base, the plastic cylinder has a belt (made of felt) constantly rubbing against one another when the equipment is switched on. This causes a sea of negatively charged electrons to be produced. The electrons travel up the belt to the metal ball of the Van de Graaf (on top). Upon skin contact with the metal ball, the person will experience their hair being "static". This is due to the fact that electrons cannot stay in one place and are always looking to leave through any form conducting medium. The person has to stand on an insulating material (e.g. wooden or plastic stool) to avoid the electrons travelling down to the ground since that pathway is natural for them. This is the same mechanism as the simple "socks shuffling against the rug" or "balloon rubbing against hair". 

When learning about wheat and rice dwarfism in class, i found some things to be similar in organization with type 1 and 2 diabetes. wheat dwarfism mimics type 2 diabetes while rice dwarfism mimics type 1 in the factors that are lost or changed. 

in wheat dwarfism, gibberellin, the protein that sends an inhibitor Rht to the proteosome, is no longer working. Rht becomes resistant, and does not get inhibited and plants stay short. There is no loss in the proteins involved in this pathway, but the gibberellin is no longer useful. Even if we were to stimulate gibberelin production in excess, it would do nothing to stop dwarfism. This reminded me of type 2 diabetes, where we still have sensors and effectors (pancreatic b cells), but we become insulin resistant. Simply injecting insulin into our blood will not solve anything because the insulin will not signal glucose transporters to bring glucose back into the cell. Insulin and gibberelin have the same issues in this case. 

In rice dwarfism, gibberelin is no longer existant but if we add gibberelin, it will stop the inhibitor. This is similar to type 1 diabetes. Although in type 1 diabetes, pancreatic b cells do not work, if we inject insulin in our blood, it will be able to bind and lower our blood glucose. Insulin and gibberelin are the same in this case as well.