bpmccarthy's blog

The domestication of animals for human use/companionship was a very long process. Since humans began forming civilizations and societies, many animals chose to stay close to human settlements to feed on food scraps that were left behind or carelessly placed. This recruited unwanted rodents to settlements that would not only eat people's food supplies, but bring disease with them. People started to notice that cats were very good at catching and killing bothersome rodents, and would entice them with food into living with or near them. Most domestication processes begin like this, with the animal in question providing a benefit for humans and in turn being rewarded with food or shelter. 

Chemistry is at the heart of all bodily processes. Understanding these processes and how they work is crucial for finding solutions to medical problems. Even something as minor as heartburn can be broken down into acid-base chemistry. When you take Tums, the active ingredient is calcium carbonate (CaCO3), which can neutralizer the overproduced stomach acids and protect the lining of the esophagus from damage. Pharmaceutical drugs rely on knowledge of chemical processes and biological pathways in order to produce the desired effect. Usually, there are many processes happening at once and sometimes drugs have other, undesired side effects along with the desired ones. Trying to minimize secondary effects plays a major part in designing pharmaceutical drugs, and often can become a big problem when trying to get a drug into production. It is hard to minimize other effects often because the unwanted effects could be happening due to a multitude of reasons. This is why getting a drug to be approved for human consumption and mass-produced can be a very long process.

Decomposition is an important part of the cycle of nutrients through an ecosystem. Decomposition is the break down of dead organic matter by bacteria and fungi, which take dead organic matter and break it down into smaller components that can be deposited back into the environment to be used by other organisms. Like many other natural processes, humans have tampered with decomposition. For one, the traditional contemporary burial methods involving filling the body with preservatives like formaldehyde slow down the process. Processes like cremation completely remove returning the organic matter to the Earth from the equation. Aside from dealing with their own dead, humans shape their environment all the time. An example of this is in the fall in colder regions, where leaves fall off of the trees. A common practice that most people adhere to is raking leaves and removing them from the yard. This doesn't allow for the leaves to be broken down by bacteria/fungi and their nutrients aren't returned to where they came from. This potentially can kill the grass in your lawn and have other detrimental effects on the local ecosystem.

The domestication of animals for human use/companionship was a very long process. Since humans began forming civilizations and societies, many animals chose to stay close to human settlements to feed on any food scraps that were left behind or carelessly placed. This unintentionally recruited rodents to settlements that would not only eat people's food supplies but bring disease with them. People noticed that cats were very good at catching and killing bothersome rodents, and would entice them with food into living with/near them. Most domestication processes begin like this, with the animal in question providing a benefit for humans and in turn being rewarded with food or shelter. 

A chromosomal translocation occurs when a segment of one chromosome becomes attached to another. In reciprocal translocations two non-homologous chromosomes exchange genetic material, and they arise from two different mechanisms: chromosomal breakage/DNA repair and abnormal crossovers. Reciprocal translocations lead to a rearrangement of the genetic material, not a change in the total amount thus, they are called balanced translocations. Reciprocal translocations, like inversions, are usually without phenotypic consequences. In a few cases, they can result in position effects and break point effects. In simple translocations the transfer of genetic material occurs in only one direction, these are also called unbalanced translocations. Unbalanced translocations are associated with phenotypic or even lethality, for example: Familial Down's Syndrome. In this condition, the majority of chromosome 21 is attached to chromosome 14. The affected individual would have three copies of genes found on a large segment of chromosome 21, therefore, they exhibit the characteristics of Down's Syndrome. Familial Down's Syndrome is the most common type of chromosomal rearrangement in humans and occurs Approximately 1 in 900 births.

Morphology refers to the characters an organism that have developed over time throughout the course of evolution. A lot about an organism's lifestyle can be understood by looking at their morphology. For example, many organisms that live underwater have common traits such as the absence of hind limbs and the presence of fins and tails. Aside from habitat, morphology can also tell us what diet an organism might have. From presence of teeth to the different shapes and forms of teeth it is possible to discern what an organism eats. A more useful way to look at morphology is the classification of animals. Animals belonging to the same family often have a few shared characters which makes it easier for us to organize them. Characters of the skull and limbs are often the most useful in determining the group a certain animal belongs to. In mammals, a lot can be said about the number and placement of digits and characters of the skull such as postorbital processes, mandible shape, presence of horns or cones, and a great number of other things. The organization of animals using morphology is mostly accurate, but can be improved upon by using genetic techniques, which can more accurately place animals together in groups using genome rather than just looking at shared characters. Still, morphology is a good place to start.

ATP itself does not give energy directly to a process that may need it, rather it is the breaking down of ATP that gives a reaction the energy it needs to proceed. The energy that ATP gives comes from energy released by breaking the bonds in its structure. The three phosphate groups attached to each other all have the same charge, and like charges prefer not to be close to one another. Given this relationship, a lot of energy is required to bond these phosphate groups together. When a reaction needs energy, the bond between the second and third phosphate group of the ATP molecule is broken, which releases a large amount of energy that can be used by reactants. Because mitochondria produce the cell’s major energy source, ATP, mitochondria are referred to as “the powerhouse of the cell”.

Competition amongst organisms in the same environment is a major force that drives species to adapt and evolve. Competition is at the foundation of the saying "survival of the fittest", as those who are best fit can compete with other organisms in their environment better and have a better chance of reproducing. Organisms in competition with each other are battling to gain control of a particular resource, whether that be food, shelter, or some other resource. The battle for these resources forces organisms to adapt and overcome the challenges that they may face when vying for control of these resources. If one organism is unfit to compete with another, it will lose easy access to resources in the area, and unless the less-fit organism can move to a new area where it can access the same resources without such fierce competition, the numbers of that organism will decline and may eventually go extinct if it cannot adapt.

Breeding animals has been a part of human history for some time now, going back to agriculture and the introduction of dogs into human culture. Dogs in particular have been subjected to a lot of selective breeding, which can be seen in every breed of dog today. All dogs have the wolf as their common ancestor, which may lead one to wonder how we got to dogs like the dachshund, or the pug. A species of dog like the pug are actually suffering due to our high level of selection. Pugs are thought of as cute because of their small, pushed-in nose. What many people don't realize is that due to this phenotype, dogs like pugs, boxers, and bulldogs have a lot of difficulty breathing as well as other health problems. While the selective breeding process has produced dogs that look cute to us, these dogs have serious underlying health issues that affect them throughout their entire lifespans. People should consider the lives these dogs live and how uncomfortable they might be due to their "man-made" morphology. Selective breeding may be good in some cases, but can have very detrimental effects in other cases.

Mitochondria are a cell organelle that are often referred to as "the powerhouse of the cell". This is due to their function of supplying the cell with energy in the form of ATP. ATP is produced as a result of many reactions carried out through the Krebs's cycle, also known as the citric acid cycle. The Krebs's cycle takes a glucose molecule and through many reactions involving electron transporters NAD+ and FADH. The final product of the Krebs's cycle brings energy in the form of electron carriers to ATP synthase, an enzyme that synthesizes ATP. The Krebs's cycle takes place inside the mitochondria, more specifically inside the mitochondrial matrix, which is located inside the inner membrane of the mitochondria. This membrane is important as it only allows the passage of carbon dioxide, water and oxygen, and facilitates proton transfer in order to make a proton gradient, which helps in the formation of ATP. The waste product in this cycle is CO, and is expelled from the body via gas exchange, where the body takes in oxygen for use in more cycles, as oxygen is an all-important final electron acceptor in the cycle.