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The aim of the paper is to investigate the characteristics of Porifera and Ctenophores in order to determine their phylogeny. Characteristics such as physiology, morphology and molecular genetics of these organisms is analyzed to map evolutionary relationships. Because these groups have not been studied extensively, making these relationships presents some difficulty. Studying them from the fossil record is a challenge because they are poorly preserved. Ctenophores are gelatinous and fragile, which makes them harder to collect. The wide diversity of porifera and ctenophores also makes them difficult to characterize. For example, ctenophores are found throughout the ocean from pole to pole. Though even with more information collected on the two species, they are often interpreted in the context of bilateria, which leads them to be labeled as less complex than they actually are. Despite the seemingly simple morphology of sponges, they have a similar genetic inventory to more complex animals. Even though the physiology of sponges is different, it carries out the same tasks and is just as complex. 

Proteins are made up of amino acids, which are molecules with a carbon center bound to a hydrogen, amino group, carboxyl group, and a "R" group. The R group vareis between amino acids. The chemistry of the functional groups is what determines the properties of ionization. Some R groups are ionizable, while others are not. Some R groups are polar and uncharged, nonpolar, or charged. In a high pH environment, the common functional groups are usually deprotonated, which means the amino group is neutral and the carboxyl group has a negative charge. On the other hand, in a low pH environment, the common functional groups are usually protonated, meaning the amino group has a positive charge and the carboxyl group is neutral. However, at the neutral physiological pH, the amino group is usually protonated while the carboxyl group is deprotonated. This is how pH affects the surface charge of a protein. In low pH or acidic environments, the surface charge is more positive since the functional groups are protonated. In high pH or basic environments, the surface charge is more negative since since the functional groups of the amino acid are deprotonated. Some R groups ionize, meaning they have a conjugate acid and base form. This means that some amino acids have three ionizable groups instead of just two. This can be determined through titration, which is when a strong base is added to an acid. At a low pH, all the groups are protonated. As base is added and the pH increases, groups begin to deprotonate. Inflection points are visible, which are when enough base is added to react with half of the acid. Then at the equivalence point, enough base has been added to completely deprotonate the acid. Based on how many inflection and equivalence points there are, one can determine the number of ionizable groups present and determine the identity of the amino acid present in solution. 

TNF-related apoptotic-inducing ligand (TRAIL), a naturally-occurring cytokine, assists in initiating the apoptotic process. TRAIL may be useful as a cancer therapy due to its death receptor binding properties for DR4 and DR5. This must be taken into account when engineering targeted treatments so normal, healthy tissue is not targeted and subsequently destroyed. TRAIL also binds to decoy apoptotic receptors such as DCR1 and DCR2, allowing for the activation of the inflammatory response and further leading the cell to apoptosis via transcription of specific genes. TRAIL may serve as part of a possible targeted treatment for pancreatic adenocarcinoma. If the protein can be transported to only cancerous cells via liposome and binding to extracellular cancer antigens, it may be able to assist in the design of an effective, holistic treatment for the patient.

Today I went to the emergency room with my friend. They have been sick for quite some time, throwing up and nausea at random times throughout the day. Over the past few days they stomach has physically started hurting and their vomiting has gotten way worse. So here I am in the emergency room and hospitals just seem so dirty. I feel like hospitals are supposed to be clean and sterile but hospitals are just the breeding grounds for the worst kinds of viruses and bacteria. Everyone who is comes here and leaves and micro organism on them here in the hospital after they leave. Superbugs have been something that have started appearing in recent years. Bacteria that have many drug resistant properties. Hospitals are responsible for inadvertently creating many of these superbugs. The doctors over prescribe antibiotics and then the bacteria continue to live and now have a gene that makes them resistant. Now that sick person comes back to the hospital or has yet to leave and leaves behind the bacteria that is now resistant to drugs. I just really don’t like being in hospitals as they seem like these bacteria and antibiotic resistant bacteria are lingering around each and every corner.

          The article “A Complete Skull from Dmanisi, Georgia, and the Evolution of Early Homo” describes archaeological finds from a site in central Asia, detailing their relevance to early hominin evolution and potentially challenging prior assumptions about human migration and species distinctions. Excavation began on the Dmanisi site in 1999, with researchers first finding assorted fauna fossils, then stone tools, and finally hominid remains. These hominid fossils have been linked to H. habilis and H. erectus in Africa and H. erectus in East Asia. The hominid remains in Dmanisi are especially important because they have been dated to 1.8 million years ago, and thus represent the earliest hominid finds outside of Africa, casting doubt on previous knowledge as to when human ancestors first traveled to other continents. One of the main focuses of the article is a particular fossil known as skull 5, which is the first and only completely preserved adult hominid skull found from the early Pleistocene. This fossil is important because it provides evidence of the orientation of the face relative to the brain case, and serves as an intact sample of fully developed adult cranial morphology, which was previously unavailable due to earlier finds being either incomplete, damaged, or juvenile skulls. Skull 5 is described as having a small brain case, a large, prognathic face, and very robust features. Skull 5 in the context of the 4 other sets of remains, also shows distinct morphologic variations, despite almost certainly being of the same species, since they were all found in the same general location and dated to approximately the same time. The notable anatomical differences in the shape of the skulls led researchers to measure the morphological variation between the Dmanisi finds and compare it to the variation found in extant ape species, like chimpanzees and bonobos. This analysis led them to conclude that the variation in the Dmanisi fossils is well within the range of normal variation within a species population. The article went on to say that such a conclusion raises questions about whether previous finds from elsewhere in Asia and Africa, which were categorized as separate and distinct species, are in fact merely part of a single widespread Homo lineage.

Evolution and acclimation are two areas of biology that are often convoluted. The former is a change over time in a population or a species such that the descendants are different from the ancestors. However, acclimation is change in an individual's physiology. Other differences between the two include heritability. Evolutionary changes in populations are heritable, while changes in individuals due to acclimation are specific only to that individual. However, the ability to acclimate itself is due to evolution. An example of evolution is observed in polar bears, which have evolved clear fur, thus matching the color of the snow. Random mutations lead to this clearness, coloration that ressembles white snow, and because of the fitness advantage, the genes for clear fur were passed on, changing the population. An example of acclimation is the tanning of human skin after long durations in the sunlight. This physiological change came about for the individual who tanned, but is reversable, and cannot be passed onto the next generation. If a person tans, their child will not be born the skin color of the parent's tan. However, humans have the ability to tan because evolution allowed them to tan. Those who were able to tan were more protected from the sun, giving them a fitness advantage.

Molecules encounter strain when their chemical structure experiences some stress which leads to an increase in its internal energy. A strained molecule therefore has a greater amount of internal energy than an unstrained molecule, and only the bonds holding the molecule together prevent the release of this potential energy. Two types of strain are steric strain and torsional strain. Steric strain (also known as Van der Waals strain) occurs when atoms are forced closer together than is allowed by their Van der Waals radii allow. The size of the groups that interact determines the amount of steric strain on the molecule. Torsional strain is dependent on conformation, and occurs when atoms that are separated by three bonds are put in an eclipsed conformation instead of a staggered conformation. This brings the atoms into close proximity and increases their potential energy, which makes the conformation unstable. Torsional strain can resist bond rotation.

Altruism is the principle or practice of selfless concern for the well-being of others. The paper The Evolution of Eusociality argues that the kin selection theory, which refers to the evolutionary strategy that favors the reproductive success of an organism's relatives, even at a cost to the organism's own survival and reproduction, is an unnecessary explanation for the evolution of altruistic behavior, or “eusociality”, and proposes alternative hypotheses based on a two-part mathematical analysis. Kin selection is based on inclusive fitness, which states that organisms can accrue reproductive benefits by helping their relatives. In doing so, they help shared genes to survive and be inherited by the next generation. Thus eusociality can evolve. However, the authors of this paper argue that inclusive fitness is unnecessary to explain eusociality. They observed ants to calculate which of two behaviours, defection or cooperation, would become more prevalent in a population through standard natural selection. They determined that inclusive fitness delivers the same result only in a limited, unrealistic solutions. When the inclusive fitness theory worked, it had no greater success than that derived from standard natural selection. The second mathematical analysis, investigated the manner in which eusociality could evolve through standard natural selection. The authors observed that whether or not eusociality evolves is dependent on the size of the ant colony and how this affects the mortality and fertility of the queen. The authors concluded that eusociality could evolve with some difficulty but is “very stable once established.”

Euthanasia refers to the practice of intentionally ending a life in the event of intolerable pain and suffering caused by an illness. This broad definition leaves room for different categories of euthanasia. It can be physician assisted or patient administered, it can be actively or passively administered on the patient, and it can involve direct or indirect assistance. This argument will focus specifically on the the morality of physician assisted suicide or voluntary euthanasia. When euthanasia is voluntary, the patient requests for the termination of their own life. When euthanasia is physician assisted, a physician carries out a procedure that terminates the suffering patient’s life.

Both physician assisted suicide and voluntary euthanasia are controversial from a moral standpoint. In order to assume a stance, one must consider and rank the importance of certain values such as the worth of preserving life, the degree of patient autonomy, and the external conditions that would justify death. There are many controversial questions that arise such as: Do patients have a right to die, and conversely do physicians have the right to kill their patients? Is it fair for patients to live against their will? Is preserving a patient’s life more important then their choice to live or die?

Figure 1. Zebra Fish Embryo

Due to the Embryo being see through we are able to see the neutral crest cells, which are red, as well as the tubulin in the microtubules, which is colored green.

The Journal of Cell Biology Vol. 201, Issue5: etoc 1

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