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Reflection about artificial insemination
Reflection about artificial insemination
Artificial insemination and its ethical concerns
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A molecular miracle occurs every time the Wood Frog faces freezing temperatures. At the point where human skin would freeze and the cells collapse resulting in frostbite, this frog’s system uses colligative properties to secrete sugars which support the frog’s cells and keep them from collapsing. Kenneth Storey, a professor of biochemistry at Carleton University in Ottawa, Canada runs tests on these amazing frogs in a laboratory with the hope of uncovering their molecular secret to surviving constant freeze thaw cycles. National Geographic article on the Wood Frog states, “Storey studies the molecular mechanics that allow wood frogs to freeze and thaw. He hopes that doctors will one day be able to copy the technique to aid human organ transplants.” Currently, the act of transplanting organs must be accomplished …show more content…
within a few hours for the organs to remain functional. The human organs cannot be frozen like the frogs because human organs lack the nucleating proteins within the frog’s cells. These nucleating proteins are often simply called antifreeze proteins. AFP’s make ample use of colligative properties to lower the level at which the liquids in the frogs cells freeze. “AFP’s bind to small ice crystals to inhibit growth and recrystallization of ice that would otherwise be fatal” (Antifreeze Protein). This allows the frog to survive sub-zero temperatures. Therefore, the wood frog does completely freeze its body, but inside the cells there is no ice.
"It can stay like that apparently, no beating heart or brain activity or anything, until you decide to thaw it," New York-based science writer Mariana Gosnell said Monday on a broadcast of the Pulse of the Planet radio program. “When temperatures warm and the ice melts, the frogs thaw. Water slowly flows back into the cells, blood starts flowing again, and the frog revives” (National Geographic). The glucose secreted by the liver is dissolved into the liquids inside the cells which then supports the cells. Though they become dehydrated they do not collapse, and the frog survives. Storey states, “The frogs, however, enter a state of suspended animation. Inside the cells there's thick sugary syrup, while outside the cells all the water is frozen” (National Geographic). This frog is a true miracle of nature. Perhaps if scientists can fully understand the process by which this frog survives it’s suspended animation, they may learn to preserve human organs for the purpose of transplanting. This little frog could spur great “leaps” for science in the near
future.
Levis, N. A., Yi, S. X., & Lee, R. E. (2012). Mild desiccation rapidly increases freeze tolerance of the goldenrod gall fly, eurosta solidaginis: evidence for drought-induced rapid cold-hardening. Manuscript submitted for publication, Available from Journal of Experimental Biology. (215, 3768-3773)Retrieved from http://jeb.biologists.org/content/215/21/3768.full
What is the most important element of a good story? Although interesting characters, engaging plot development and didactic story lines certainly embellish the story, one could argue that the setting is the most crucial. Not only does the setting provide a baseline of necessary background information, it can also be used to enhance the story, just like the other elements listed. Edgar Allan Poe certainly takes advantage of this in “Hop Frog”, “The Cask of Amontillado”, and the “Masque of the Red Death”. In each of these stories, gruesome horrors occur, and because of the ingenious way Poe uses and manipulates the setting to his advantage, these stories’ horrors are amplified. In “Hop Frog” and “The Cask of Amontillado”, the main characters
ohn Steinbeck's “Cannery Row” offers many interpretations, especially when viewed through the lens of the Holy Bible. From the Christ like figure of Doc to his apostles, Mack and the boys, Cannery Row is ripe with religious tropes. However, Doc is also considered to be quick to anger at times, and carries with him many themes found throughout the Old Testament texts and some legends that are even more aged. However, if we consider Doc to be the messianic figure he is then it wasn't the party that Doc had a problem with, nor that it was held without his knowing on his property. The issue arises with the process by which Mack and the boys use to fund the party. The green frogs harvested ultimately causes Mack and the boys to succumb to greed in an effort to praise Doc. The collection of frogs used as a currency is what sends Doc into a rage.
The short story of “Hop-Frog” by Edgar Allan Poe is about a crippled jester, Hop-Frog, and his friend, Trippetta, who were captured from their homeland and were delivered to suffer at the hands of a king and his seven ministers. They were abducted and sent to the king for his entertainment. However, the king and his seven ministers enjoyed making practical jokes of the crippled jester. Hop-Frog experiences injustice from the King severely and tolerates it to the point in which he cannot anymore. After years of bearing the brunt of the king 's mocking sense of humor, Hop-Frog was pushed past his limits when Trippetta was insulted by the king in front of him. Due to the King 's extreme abuse, Hop-Frog undergoes trauma and seeks revenge. As a
Poison arrow frogs are one of the most interesting animals of the Amazon rainforest. Poison Arrow Frogs are very colorful. The Poison arrow frogs skin holds all of the poison. Female Poison arrow frogs lay eggs in the water which then turn into tadpoles, when nursing the tadpoles stay on the females back. They’re colorful and vibrant body warn predators to not go near them. Most Poison arrow frogs are a bright colored. The Poison arrow frogs scientific name is Dendrobatidae. Poison arrow frogs are not poisonous in captivity. They gain their poison from bugs and arthropods that they eat. Poison arrow frogs gained their name from indian tribes putting the Poison arrow frogs poison on darts and arrows. Poison arrow frogs are small and about a centimetre tall and wide. The most poisonous part of a poison arrow frog is the Poison arrow frogs skin that can kill a 180 pound 6 ft man but usually it isn’t bad. All Poison frogs are poisonous but only 3 are deadly. The most poisonous and deadly Poison arrow frog is the famous Golden arrow frog. Its poison, Batrachotoxin can kill small animals and humans. As you can see Poison arrow frogs are unique and colorful frogs.
They have now invented a “beating heart transplant.” It consists of a mechanical system to keep the heart beating, while it is being transferred to the candidate. Statistics have proven that these candidates have a higher recovery rate, because of the “beating heart.” Throughout reading above, it is a given that organ donation is vital to saving lives, but it is not deemed proper to be made mandatory.
Currently 70,000 Americans are on the organ waiting list and fewer than 20,000 of these people can hope to have their lives saved by human organ transplantation.1 As a result of this shortage, there has been a tremendous demand for research in alternative methods of organ transplantation. Private companies are racing to develop these technologies with an estimated market of six billion dollars.2 Xenotransplantation, or cross-species organ transplantation, appears to be the most likely solution in the near future, and cloned pigs are the main candidates. Pigs and humans have remarkable similarities in physiology, which along with cloning makes pigs strong possibilities for organ donors. A controversial alternative method involves the use of genetically altered headless human beings as organ donors. Although this method may not be developed for some years, scientists are already discussing the necessary technologies. Whether the solution is the cloning of a pig or a human, organ farms may provide us with a solution to our ever-increasing need for donors.
...ous cytoplasm in the physical confirmation that was proposed. Same as if oil and water being left to stand, after being shaken will separate, meaning the hydrophilic and hydrophobic elements will sort themselves out into the correct order to isolate them from contact with the polar components. They supported their theories with both physical and biochemical evidence. During research they had successfully took apart the bilayers of frozen cell membranes from different areas to show the proteins embedded inside, other evidence had also shown to support that transmembrane proteins exist.
On a cellular level, Mrs. Jones’ cells are dehydrated due to osmotic pressure changes related to her high blood glucose. Cells dehydrate when poor cellular diffusion of glucose causes increased concentrations of glucose outside of the cell and lesser concentrations inside of the cell. Diffusion refers to the movement of particles from one gradient to another. In simple diffusion there is a stabilization of unequal of particles on either side of a permeable membrane through which the particles move freely to equalize the particles on both sides. The more complex facilitated diffusion is a passive transport of large particles from a high concentration of particles to a lower concentration of particles with the aid of a transport protein (Porth, 2011). The cellular membranes in our bodies are semipermeable allowing for smaller molecules to flow freely from the intracellular to extracellular space. The glucose molecule, however; is too large to diffuse through the cellul...
There have been numerous developments in the subject of biotechnology. One of these advancements contains xenotransplantation. It is the transplantation of living tissues, cells or organs from one species to another. For example, it covers transplantation of vital organs like heart, kidney and also skin graft, bone transplant s, corneal transplants. The purpose of human xenotransplantation is that it proposes a possible solution for the problem of the shortage in human organs because the number of accessible organs is not equal to the number of needed organs. For instance, according to M. Anderson’s article the number of people waiting for an allotransplant (it refers to a same-species transplant such as human-to-human.) is progressively increasing without organ donations. In addition, approximately half of those demanding an organ transplant will die while on the organ donor waiting list (Anderson 205). Furthermore, it can also be used to treatment other illness where there is a scarcity of human material accessible such as Alzheimer, Parkinson, diabetes. As we can see, in theory xenotransplantation provides good solution for human beings, however, when look at the history we cannot see same good things. For instance, in 1964, a scientist who is Keith Reemstma transplanted a chimpanzee kidney into a human with end period nephritic disease, increasing the participator’s life a record nine months (Anderson 205). However, there is another case which is Baby Fae. In this case doctors transplanted a baboon hearth into the baby and he survived just four w...
Frozen cells can be kept alive for very long periods of time in a state
Ecosystems are the basic biological units of ecology, and consist of biotic organisms and their interactions amongst other living organisms, as well as the surrounding abiotic environment (Putman and Wratten 1984). One facet of ecosystems that is less-often mentioned is the process of decomposition, as it many may view it as an unclean, unpleasant process that occurs after an organism has ceased to exist. To those with an ecological framework, however, decomposition is viewed as the opposite – an interesting, intricate process teeming with biological activity and life (Swan and Kominoski 2012). What is decomposition? Formally, decomposition is defined as the process to which complex organic matter is broken down to its basic constituents (i.e.
Retrieved December 30, 2013, from http://www.benbest.com/cryonics/CryoFAQ.html#_VD_.
“Transplanting animal organs into humans is feasible.” USA Today. November 1999: 54-55. Gehlsen, Gale M., Ganion, Larry R. and Robert Helfst.
With many causes of organ failure that led to a death sentence a long-term treatment needed to be found. In December 1954, the first organ was transplanted from living donor to living recipient, who was between twin siblings, was to be the next direction of treatment. With the invention of an immunosuppressant cyclosporine, the cure was thought to have been found for organ failure. It would have been the answer to the organ failure until the procurement laws were not able to keep up with the need for organs, which formed a list of patients called the United Network for Organ Sharing (UNOS). The scientist and physicians went back to the drawing board to come up with bioengineered organs with the used of stem cell on matrices. Multiple biometrics are being used for the bioengineered organs. Introduction At a point in history, any type of organ failure was a death sentence. Many causes lead to an organ failure, whether it is from congenital causes, abuse, or illness it is an unfortunate circumstance. This was the case until December 23, 1954 when the first live organ transplant was performed in the United States, which was from a living donor to living recipient. The first transplant ever conducted was on an individual that needed a kidney, which was conducted using identical twins (Kaserman Ph.D, 2007). The new technology lead to a completely new list of trails in the organ transplantation field that would lead to a huge change in the future of medicine, and that of the individuals that need the lifesaving procedures. These trails became easier in 1983 with the invention of immunosuppressant called cyclosporine, which allow for cadaveric organ donation (Kaserman Ph.D, 2007). Unfortunately, the law for organ procurement could not kee...