Writing in Biology

Jean Baptiste Lamarck was a French naturalist. He was the first to research invertebrate animals, and an early advocate for the idea of evolution. He had a discredited theory that evolution occurs when parent organisms pass on acquired traits to their offsprings. Now, we widely believe in Darwin's theory that evolution occurs because of natural selection.

However, new research findings suggest that Lamarck's theory might have some truth to it. We now know that hereditary epigenetic changes violate Mendelian principles. Epigenetic changes occur by transcriptional modifications: due to alterations on histone tail charges, chromatin binding, X-chromosome inactivations etc.  Although these changes pass on from mother to daughter cells, the modifications are typically erased in the germ cells. However, accumulating evidence suggests the opposite: passing on of epimutations. So far, the phenomenon has been spotted in plants, fruit flies and yeast.

However, scientists nowadays are starting to think that perhaps Lamarck's theory wasn't completely outrageous. The reason behind this phenomenon is because hereditary epigenetic changes seem to violate Mendelian principles. Epigenetic changes occur by transcriptional modifications due to alterations on histone tail charges, chromatin binding, X-chromosome inactivations etc.  Although these changes pass on from mother to daughter cells, normally the modifications are erased in the germ cells. Recently, however, accumulating evidence suggests the opposite: passing on of epimutations. The phenomenon "has been spotted in plants, fruit flies and yeast". There was also a major study in mammals that indicated towards epimutations heredity. 

A hormone is a substance produced in the body that directs and regulates the events occuring inside of certain cells or organs. Hormones are classified by both how they travel in the body and their chemical structure. There are five classifications based on how they travel in the body; endocrine, paracrine, autocrine, intracrine, and juxtacrine. Endocrine hormones act at distance over the body, while paracrine hormones act within the tissue they are synthesized. Autocrine hormones act on the cell they are produced by; they are secreted and then attach to the receptors on the surface to trigger a reaction. Intracrine hormones also act on the cells they are produced by, but they act directly inside the cell rather than through the receptors on the outside of the cell. Juxtacrine hormones act on juxtaposed cells. They are chemically classified into four groups; amines, peptides/proteins, steroids, and eicosanoids... and are also classified as either water-soluble or lipid-soluble. Amines and peptide/protein hormones are water-soluble and target cells by acting on receptors on their membranes. Steroids and eicosanoids are lipid-soluble and thus can penetrate the cell membrane and act within the cell.

The ribosome is another organelle in the cell that has an extremely important role. These tiny, but essential structures should not be overlooked, as they perform functions that are necessary for human life. Ribosomes are found on the endoplasmic reticulum or in the cytoplasm. When they are attached to the endoplasmic reticulum, it is known as the ‘rough’ endoplasmic reticulum. The ribosomes contain important RNAs named the ribosomal RNAs which help the ribosome carry out its main function; protein synthesis. This process is seen in translation; the ribosome uses the mRNA strand to form a completely new protein. From there, the polypeptide chains can be synthesized into tertiary and quaternary structures. Proteins are essential to human life and carry out a myriad of chemical functions. 

During the rise of the Amniotes over 330 million years ago, a shift in skull formation took place that is now being used to classify ancient organisms that used to roam the Earth. As a little background, the Amniotic family includes subfamilies like mammals, testudines (turtles), Lepidosauria (lizards, snakes, etc.) and the rest of the vertebral phylogeny. Each subsequent family is unique in that their dermatocranias each formed a fenestration, or hole. The location and number of holes in the skull allow us to classify the organisms into smaller groups. For example, an anapsid organism has no fenestrations in its skull. An organism, like a lepidosaur, would be a diapsid organism and have two fenestrations in its skull. The first of which is the dorsal fenestra located at the junction of the parietal, post orbital, and squamosal bones. The second is the lateral fenestra located at the junction of the jugal, quadratojugal, squamosal, and post orbital bones. Lastly, mammals are synapsid organisms meaning they only have one lateral fenestra in their dermatocranium.

Previous to the appearance of modern wildlife tracking technologies, little was known about many aspects of the life histories of marine creatures, including how they use space and their migratory habits. A long-term study performed by researchers in the coast of South Africa used photographic identification data since 1997 for recording white shark activity in Gansbaai. With the development of electronic tagging devices such as acoustic tags, PAT tags, and satellite tags, the researchers were able to take their study a step further and discover where white sharks go when they are not roaming along the coast of South Africa. Among the tagged white sharks of their study, a female classified as P12 performed the fastest return migration ever recorded in a marine animal, when it traveled to Australia and back to its natal range in South Africa in less than 9 months, navigating more than 20,000 km at a minimum speed of 4.7 kilometres per hour. Although more data from individual migrations of white sharks should be recorded, this first transoceanic journey suggests a connection between two important populations in South Africa and Australia, and offers important information for conservation efforts of endangered marine fauna.

The central dogma of microbiology is the idea that there is movement of information from our genome to a movable RNA strand, and then it is translated into a protein. In relation to cancer, this process is extremely important because the function of the protein can be traced back to the coding of the DNA. Any issues with said protein could help identify how cancer cells pass down cancerous behavior, how such a behavior is transcribed, and what happens when this protein tries to function. The mutation in a genome can elicit a mutation in a proto-oncogene (pushy positive proteins in healthy cells) and tumor suppressors and thus a tumor is now able to form. When a proto-oncogene is mutated it becomes an oncogene and always remains active, signaling to the cell to continuously grow and develop without stopping.

Most animals use sound as a form of communication and with it are able to express many different things. It is often a key factor in survival and in many cases, if an organism cannot communicate properly or well enough, they may not survive. In some gull species, there are certain sounds used for specific needs, such as finding a mate, locating food, or claiming territory. These sounds are also often used in different scenarios based on the time of year. Sounds used to find a mate for example, are later used to communicate with that mate when caring for the young and finding food. The sounds are versatile and have different meanings based on the context. The sounds of birds is recorded and analyzed for different measurements when studied. The band width of sound can be measured by subtracting the lower frequency from the higher frequency. There is a bigger difference between the high and low frequencies in wide bandwidths and a smaller difference in short bandwidths. The trill rate is how often a sound is made, or how quickly. The trill is known as a high performance form of communication, because it requires a lot of energy. There is a trade off between these two sounds because one cannot have a wide bandwidth as well a high trill rate, the bird is incapable of doing both really well at the same time. A higher or faster trill rate is accompanied by a short bandwidth because it is too difficult to have a wide bandwidth and fast trill rate.

Quantifying communication will be done using bioacoustic analysis. For starters, sound is places in the air where molecules are compressed in some areas, and less compressed in others, these less compressed areas are called rarefractions. Sound is a change in air density, so what we hear is compression of air particles. We can measure the amplitude, which is the amount of energy. This is what we perceive as loudness. We can also measure frequency, which is what we perceive as pitch. Frequency is how often the sound wave occurs. A higher frequency occurs at a higher pitch. 

Many animals use sound as a form of communication, as do we. One of the most commonly studied form of animal communication is bird songs. They have been studied since the beginning of people studying how animals communicate because there are a lot of different variations and it is very easy to observe and record bird sounds. In birds, you can measure what is known as the band width by subtracting the lower frequency from the higher frequency. There is a longer difference in wide bandwidths and a smaller difference in short bandwidths. You can also measure the trill rate which is how often they create this noise. The trill is known as a high performance form of communication. There is a trade off between these two sounds becasue one cannot have a wide bandwidth as well a high trill rate, you cannot have both really well. So a higher or faster trill rate is accompanied by a short bandwidth becasue it is too difficult to have a wide bandwidth and fast trill rate. 

Sounds used by birds can also be used to signal different things even though they might be the same sound. In some gulls, they have certain sounds used for finding a mate that are also used when trying to communicate with that mate when it comes to finding a place to nest. They have some other sounds that overlap when mating and then when caring for the young. They have the ability to use the same sounds but interpret them differently based on the context of the situation. 

Following the completion of the image manipulation in Microsoft Paint, the images were all saved. I then imported them all to a newly created project in the software Inkscape. Each image was appropriately resized and arrayed on the page. The photo of the web was placed to the upper-middle left side of the project. Equivalent in size, the second image of the location was placed to the right of the first. A small white gap was created between the two photos. Both ends of the images connected with their respective ends of the figure. Next, the screenshot of the map was placed at the center below the first two images and was slightly larger so that the details of the map could be clearly seen. Finally, each figure was labeled with the web being denoted at “(A)”, the location as “(B)”, at the map as “(C)” These labels were placed near the top right corner of each component of the figure. The overall construction of the figure was done in such a way that every element was could be seen clearly and understood.