Thursday, March 12, 2020
Objectivity of Science
Objectivity of Science Introduction The history of objectivity of science can be traced back to the nineteenth century. The objectivity of science was based on the truth, facts and knowledge. It was practiced by scientific atlas founders so as to articulate the presentations of the meaning of nature.Advertising We will write a custom essay sample on Objectivity of Science specifically for you for only $16.05 $11/page Learn More The need by scientists to restrain themselves from using their individual bias in the description of nature was the fundamental driving force behind scientific objectivity. The guiding principle in scientific objectivity has always been and will always be ensuring that knowledge is safeguarded from biased individual representation. Science is founded on the objective analysis evaluation and presentation of scientific, empirical data based on the facts observed (Kuhn, 1973, para. 3). Scientific objectivity is the term given to the practice of science through which different facts are investigated and subsequently used to explain different untruths. The elimination of personal biases and emotional commitment are the core of scientific objectivity. Objectivity has been used as a standard of measure in science for quite some time. The objectivity of science is closely associated with the ability to test the facts. For science to be considered to be objective, measurement of facts must be disseminated from one person to another. The test of objectivity encompasses other various tests.Advertising Looking for essay on philosophy? Let's see if we can help you! Get your first paper with 15% OFF Learn More It has been observed that the classification of traditional objectivity overlooks numerous elements (Kuhn, 1973, para. 8). Therefore, objectivity of science follows certain values and facts. Scientific objectivity, values, or facts The test of objectivity has various subjective decisions which make the entire measureme nt involve reductionist process. On the other hand, the measurement of these methods will form part of the objective test related to the outcome of the facts. A fundamental element of science, which is emphasized by a lot of scientists, is that, emphasis is placed on the facts but not the values involved. This distinction has been openly revealed since science exists on the objective reality and while values do not. This perception enables scientists to perceive the field of science as a domain of permanent knowledge, which must be identified. The notion of science being free from value has been highly contested by sociologists and scientists. The criticism is based on the methods used to arrive at several scientific conclusions (Restivo, 2011, p. 21). There are various misconceptions whereby the value of free nation is claimed to have been overrated and overstated by scientists. The ideology of relativism between science and objectivity has been held to be misleading. There are tho se scientists who contend that the sciences have values meant to assist in arriving at reliable knowledge free from effects of bias. An element of bias would lead to unreliable knowledge.Advertising We will write a custom essay sample on Objectivity of Science specifically for you for only $16.05 $11/page Learn More The intersection of knowledge and values has been identified. The intersection of knowledge and values has provided robust facts. The diversity of values promotes accepted principles (Polifroni Welch, 1999, p. 18). It is still contested that the notion of science being pure and not relying on values is highly misleading. It is known that science promotes values such as reliability, accuracy and precision. On the other hand, scientists are said to value novelty and simplicity of concepts. It has widely been argued that the pursuit of science is a value based venture. There is a need to consider science and how it operates in the development of t he material world to acquire and develop knowledge. However, this may be unreasonable not to weigh the stakes involved. Scientific objectivity proves that values are not excluded from the quest for knowledge in science. In its core components, science is not only made up of freedom but also of responsibilities. The fundamental elements, which are noticeable, in scientific objectivity, have a refutable hypothesis. The hypothesis must be backed with relevant evidence. Finally, the results should be presented in a way that they are accessible and can be subjected to empirical testing by all individuals with a vested interest in science (Okasha, 2002, p. 43).Advertising Looking for essay on philosophy? Let's see if we can help you! Get your first paper with 15% OFF Learn More It is the underlying core values that limit a scientific research from replicating someone elseââ¬â¢s work while expecting different results. The standards placed on research have made it easy to identify whenever certain conditions have been breached. The use of refutable hypothesis brings the scientific objectivity to a point that the knowledge identified is placed in an objective, rigorous test. The strict requirements that the information offered should be tested can be used to promote scientific reputations. Some scientists will gain wide use of reputation due to their knowledge of documentation. The scientific field has automatic activities (Laudan, 1983, p. 16). The objectivity of science is not limitless since it has numerous limiting factors. Objectivity has numerous problems, which are associated, with metaphysics. This has been mainly linked to the objectivity of the mind. The objectivity of the mind exists with several ethics, and a consideration of these ethics is th e account of the objectivity. It follows that objectivity is a method of understanding whereby knowledge and beliefs are placed in a primary sense of understanding. The main truths that can be placed in the above definition qualify to be a formation of conception. The old view, which is to be regarded as subjective, yields an objective conception (Keller, 2009, p. 16). The objectivity test has been said to yield the expected results, which have been described by some scientists as false objectivity. The perception of the larger reality supposes that we are to be considered as being part of the larger reality in the objective standpoint. The implication of the statement above implies that there is a connection between reality and objectivity but the connection could be remarkably small. The question as to whether the mind and self-form part of the objective reality remains unanswered. The objective status in the mind creates a mental status which tends to be general. The objectivity of the mind dictates that there is a significant link between the brain objectivity and the day to day actions in ones life. The physical properties define the scope of the mind objectivity. The definition given to the physical world has been said to emanate from a standpoint of human beings perceptions (Okruhlk, n. d). The very evidence that every scientist begins to work on every day is based on the perceptions of individuals and their rational understanding of different events in the physical sphere. That clearly supports the assertion that objective conception is not without origin, but it has a starting point and reliable features. The properties of the perpetual aspects of objective science are better understood when the beginning is traceable. The mind has the rational consciousness, which gets the information, and basing on this information, a perpetual point of view is taken. As proven conception of objectivity has its own difficulties and limits as it was earlier mentioned . In the same way that the brain has a limit to the affairs going around it, the brain too has notable difficulties when seeking a clear understanding of reality (McMullin, n. d). The objectivity is limited by the fact that the interpretation of different perceptions, which cannot be severed from the occurrences due to the physical interactions. The mention of mental activity in the objectivity of science is to make sure that all perceptions and viewpoints are concurrent with the practice. Reality objectivity leads to conclusions that so perceptions have a dominating role in the physical world. Scientists have at numerous situations considered the objectivity to be a myth which they have continuously sought to affirm or dispute. The mode of arriving at substantial results too has been placed on the basis of the said consideration (Fleming, 2004, p. 17). The scientific objectivity has existed with numerous criticisms from scientists and sociologists. There are scientists who have arg ued that the scientific objectivity among many scientists has occurred in the form of an illusion. The objectivity advocated by scientists has been said to be hard to achieve. The objectivity applicability in the real world is held to be impossible, but such notions have continuously been disputed (Kuhn, 1973, para. 9). Conclusion It is evident that the objectivity of science follows certain values and facts. The scientific objectivity as put across by different scientists has many elements and many scientists have tried to justify the existence of the main features. In some instances, it has been asserted that objectivity does exist without values, but that assertion has been widely disputed. The existence of values such as novelty in the objectivity of science has been a pillar to the contention that there are no values in scientific objectivity. However, there are many problems that scientific objectivity ought to deal with accurately. References McMullin, E. (n. d). Rationality and Paradigm change in science. Retrieved from fitelson.org/290/mcmullin_acfsr.pdf Fleming, B. E. (2004). Science and the self: The scale of knowledge. Dallas [u.a.: Univ. Press of America. Longino, H. (n. d). Values and Objectivity. Retrieved from cumc.columbia.edu/dept/healthandsociety/events/ms/pdf/ps_Longino%20H%20Values%20and%20Objectivity.pdf Okruhlk, K. (n. d). Gender and biological sciences. Retrieved from http://spot.colorado.edu/~cleland/articles/gender_and_biological_sciences.pdf Keller, A. C. (2009). Science in environmental policy: The politics of objective advice. Cambridge, Mass: MIT Press. Kuhn, T. (1973). Objectivity, Value judgment and Theory choice, Retrieved from http://commonsenseatheism.com/wp-content/uploads/2010/04/Kuhn-Objectivity-Value-Judgment-and-Theory-Choice.pdf Laudan, L. (1983). Dissecting the Holist Picture of Scientific Change. Retrieved from: scribd.com/doc/96495571/Dissecting-the-Holist-Picture-of-Scientific-Change-Laudan Okasha, S. (2002). Philos ophy of science. Oxford [u.a.: Oxford Univ. Press. Polifroni, E.C., Welch, M. (1999). Perspectives on philosophy of science in nursing: An historical and contemporary anthology. Philadelphia: J. B. Lippincott. Restivo, S. P. (2011). Red, black, and objective: Science, sociology, and anarchism. Farnham, Surrey: Ashgate.
Tuesday, February 25, 2020
Practical Considerations in Gene Therapy Essay Example | Topics and Well Written Essays - 2000 words
Practical Considerations in Gene Therapy - Essay Example The important practical considerations pertain to applications, problems, ethics, communications, and prospects. Using the perspective of Culver (1994a), Cotrim and Baum explained that gene therapy is a procedure that ââ¬Å"typically involves the insertion of a functioning gene cells to correct dysfunction or to provide new cellular functions.â⬠Culver (1994a) is a physicianââ¬â¢s handbook on gene therapy. In 1994, Culver (1994b) had already outlined a procedure for the clinical applications of gene therapy for cancers. When a medical situation involves defective genes, an option to use gene therapy arises. Some of the diseases that result from defective genes include immunodeficiency syndromes, muscular dystrophy, cystic fibrosis, hemophilia, and many types of cancers (Cotrim and Baum 2008, p. 97). Another perspective on gene therapy comes from the United Kingdom Parliament Office on Science and Technology. According to the Office (2005, p. 1), gene therapy ââ¬Å"involves the introduction of genetic material into a cell to treat disease.â⬠Finally, another alternative definition of gene therapy is ââ¬Å"transferring recombinant genetic material (DNA or RNA) to the host cell in order to change the gene expression in the host cell in order to change the gene expression in the host cell to attain therapeutic effect.â⬠Most likely, the definitions we choose to adopt or highlight can be associated with the specific therapy or ailments on which we want gene therapy to work.
Sunday, February 9, 2020
Topic of the paper will focus on a criminal case that has been Essay - 1
Topic of the paper will focus on a criminal case that has been adjudicated by the United States Supreme Court and has implications on the criminal justice system - Essay Example The court thus proceeded to assign him one by the name of Kirk McAllister who was a veteran defense lawyer. As the case proceeded, however, Scott Peterson later stated that he would be able to afford a private attorney after all and hired the services of Mark Geragos who had handled other high profile cases similar to his (Crier & Thompson, 2005). The judge appointed to the case later on moved the trial from Modesto, California where the crime had been committed to Redwood City in the year 2004 due an increase in hostility towards the defendant (Scott Peterson). The judge felt that due to this hostility, the judge felt that Scott would not be able to receive a fair trial in Modesto as individuals in that region had already perceived him as guilty and it would have been impossible to get a non bias jury in that area (Beratlis et al, 2007). The hostility was due to the type of coverage that the case received from the media. (Bird, 2005) The news had already portrayed Scott Peterson as an inhumane individual who was accountable for the death of an innocent woman and an unborn child. They covered the story as if the defendant was guilty, and the process of the trial was just a preliminary to the inevitable end result of a guilty verdict. In order to ensure that Scott Peterson would be able to get a fair trial, the judged moved the case to another area away from Modesto, where the residents felt bereaved as they had lost one of their own. It should b noted, however, that the coverage of the country was country wide, and thus it cannot be said how much the move changed matters in terms of the defendants portrayal (Beratlis et al, 2007). The main witness of the prosecution also hired her own attorney who played a big role as a sympathizer to the prosecution as she was not bound by the gag order that prohibited the others who were involved
Thursday, January 30, 2020
Persuasive speeches Essay Example for Free
Persuasive speeches Essay In order to begin this piece of work we looked at persuasive speeches in our lessons. These speeches were from famous people, such as Hitler and Tony Blair. However, my personal inspiration came from a speech from Diana Princess Of Wales, entitled, Women and children with aids. This acted as a style model for my final piece and gave me the basis for my ideas. As well as this it helped in my planning, as I could see which techniques were the most effective and how to craft the piece for maximum effect. My original idea was to write a persuasive speech about the very serious issue of poverty. However, I found it difficult to write a long enough speech to fit into the word count. I therefore changed my idea to writing a persuasive article and this is my final piece. The genre of this article is to persuade and it is written for an adult audience. The intention; to persuade, is brought across very well as many persuasive techniques are employed. Rhetorical questions, How will she live with no food? are used to make the reader reflect and ask themselves questions. Moreover, facts and figures, 9. 5 million , use of imperative, we must. , repetition, reference to expert studies and emotive language are used to persuade the reader further. The tone of the article is serious and reflective, however it is clear and to the point. This helps the purpose of the piece come across more clearly. The intended effect on the audience is reached as it stimulates the reader to reflect on themselves and other people, gently persuading the reader unconsciously. The structure of the article is clearly set out with a strong opening and ending. There is more descriptive language in the middle of the article as well as facts and figures used to back up statements. This makes the piece simple to read but effective at the same time. The lexis which is used is more challenging for the selected audience, acknowledge, desperation, judgemental. The lexis would be much more simple compared to an article for a child. The idea of helping the dark shadow of poverty fade and reaching the light at the end of the tunnel are used as figurative language features. This was also used as emotive language to stimulate the audience and their emotions. The successful aspects of this article include the lexis, which I have chosen to complement the genre, the shaping of the writing to the selected audience, as well as the purpose. The pictures help the graphology of the article to come across and shows the reader real life images, helping them to picture the situation and feelings of those in poverty. Moreover, the facts and figures are used to back up statements and provide the reader with realistic, additional information. This keeps the reader interested and aware that the truth is being told. The contrasts between facts and descriptive emotive language are also successful as it breaks up the information and does not over load the reader. The ways to improve the article are to use more imperatives, e. g. we must we can. This will help the audience become more involved and feel as though they can actually help. As well as this, more usage of metaphors, similes and other language features could be used to make the article more interesting. Personal opinions could be used to persuade the reader even more or more than one point of view could be adopted to give the reader freedom of choice.
Wednesday, January 22, 2020
Various law :: essays research papers
Charta Magna: agreement between king John and his barons laying down mutual rights and obligations as well as the position of the lower nobility and the church. (1215) Habeas Corpus: is an important remedy against unlawful commitment. (1679) Bill of rights: protects statements in either house of parliament granting parliament itself the power to fine or imprison those who abuse this privilege. It also prohibited the king to levy taxes or keep an army without permission of parliament. (1689) Act of settlement: Secured the succession of the throne after the death of William III who was king of England but who didnââ¬â¢t have any children. It gave the throne to Princess Sofia of Hannover and her heirs, being Protestants.(1700) Charles-Luis de Montesquieu : ââ¬Å"De lââ¬â¢espiritu des loisâ⬠(1748) Jean-Jaques Rouseau is the author of: ââ¬Å"discours sur l' origine el les fondaments de l' inegalite parmi les homesâ⬠(1754) ââ¬Å"contrat social ou principes du droitâ⬠(1762) Independence of USA (1776) French Revolution (1784) Types of laws Statute laws: An act of the legislature of a state or country, declaring, commanding, or prohibiting something; a positive law; the written will of the legislature expressed with all the requisite forms of legislation; -- used in distinction from common law. Statute is commonly applied to the acts of a legislative body consisting of representatives. In monarchies, legislature laws of the sovereign are called edicts, decrees, ordinances, rescripts, etc. In works on international law and in the Roman law, the term is used as embracing all laws imposed by competent authority. Statutes in this sense are divided into statutes real, statutes personal, and statutes mixed; statutes real applying to immovables; statutes personal to movables; and statutes mixed to both classes of property. Statute book: a record of laws or legislative acts. Federal Laws: Rules that are applied on a federal level International Laws: A set of rules generally regarded and accepted as binding in relations between states and nations. Also called law of nations. These are the rules regulating the mutual intercourse of nations. International law is mainly the product of the conditions from time to time of international intercourse, being drawn from diplomatic discussion, textbooks, proof of usage, and from recitals in treaties. It is called public when treating of the relations of sovereign powers, and private when of the relations of persons of different nationalities. International law is now, by the better opinion, part of the common law of the land. By-laws: A local or subordinate law; a private law or regulation made by a corporation for its own government.
Monday, January 13, 2020
My Past, Present, and Future
Hard life does not equal reason for failure, but reason for determination. Even though it may seem with so much bad you are bound to fail, with all of my bad I'm bound to succeed. I have been through a lot in life, just as every single mother but I still have what it takes for my future success. Do you have what it takes for a brighter future? The first reason I believe hard times give you determination, is because I had a hard childhood growing up. Beginning with my father abusing my mother and he was never around, a mother who was struggling to figure out who she was and what she wanted in life, and how to take care of a teenager with so many bad experiences. My father was murdered in front of me and passed in my arms when I was seven years old. My only father figures I had left were my brothers who for their own reasons couldnââ¬â¢t be around much. I turned to alcohol at a young age thinking it would make my life better. I felt as if I was alone. I didnââ¬â¢t know I had people that would be there for me. All I knew was my immediate family and my friends, which were not good influences. My mother had turned to alcohol as well and I was always home alone or with my uncle John. I never wanted to go to school; however, my uncle encouraged me to do so. I continued to attend school and did the best I thought I could. I got into skating thanks to my uncle and that is how I got rid of my stress if I had it. Uncle John always took me and my friends to the skating rink to enjoy time, just as a young child should. It made things better for me for awhile I had my father figure back again, but still needed my mom. I was lost and had no guidance; so much had happened to me at such a young age and that affected my life because I believe no matter what happens you canââ¬â¢t erase your bad memories. My beliefs are stated by Sigmund Freud, he said ââ¬Å"The world as we know it is stored in our conscious mindâ⬠(Witt & Mossler, 2010, Ch. 2, Pg. 2). Additionally, at age fifteen I was involved in a car accident that everyone including myself thought it ended my life. I was pronounced dead on scene yet revived. I was hospitalized for over a week and had to go though therapy to learn how to walk again. My brain wasnââ¬â¢t coordinating with my legs. I broke five ribs, my lung collapsed, crushed my heel, burned my back, my scalp was avulsed, broken nose, and in general shaken up. I woke up to a paramedic by my side coaching me through my breathing and having faith in my ability to overcome anything. It just so happened with me living in a small town that paramedic was my best friendââ¬â¢s father, Gene Deck. Thatââ¬â¢s when I got my mom back, and to this day she is always there for me and is my best friend. During that time I had also lost my brother who meant the world to me. He was my role model and was everything to me. I would wait for him every day on the porch to arrive from work. He had been though a lot himself and had went to prison for a few years. He got out of prison and started his life over working in the oil fields, I still remember his smell. It was that time of year for our family reunion, we went camping every year. I remember waking up to his face at five in the morning and him asking me to go on the boat with him to check the trout lines, me at my age was upset about being woke up that early. I pulled the blankets over my head and said ââ¬Å"go away and leave me alone bubbaâ⬠. Those were my last words to him, which is why I strongly believe you should make sure your words to your loved ones are that from the heart. He had gone out on the boat and it had a hole in it, my brother didnââ¬â¢t know how to swim. They found him late that night after searching all day at the bottom of the river tangled in seaweed. With all those experiences, I knew what I wanted to do as an adult, save lives. So I took it upon myself to try and get my life together and do what was right. I had several inspirations for saving lives, from my life being saved to maybe I could have saved my brothers. I had so much encouragement in my heart now to move forward with my career choice in the future. For now, it was time to focus on finishing high school and being a good daughter so that my mom wouldnââ¬â¢t have to go through anymore pain. I focused on school and promised myself no matter what happened in life I would return the favor given to me from the man upstairs, with a second chance given to me I would help saving lives. It is thanks to God that I am alive today, and for the rest of my life I will thank him every day. I may not be one of those people who go to church every day, but I do know my life is held in the hands of a man that I owe my life to. At age seventeen I ended up being getting in another relationship that I thought would last forever and we decided to have a child. I ended up having too many medical problems and had to drop out of school. I was determined to keep my promise. I set out to get my G. E. D and started running with the Emergency Medical Service in my town as a rider. I then became part of the EMS family as a driver. They paid to put me through school to become an Emergency Medical Technician. I decided that wasnââ¬â¢t enough and started school with a technical school to become a National Registered Certified Medical Assistant. My first born son gave me more inspiration to better myself in life. He was the reason of my existence and the reason I to this day work very hard at everything I do to succeed in life. I named him after my brother that had passed, Keith. I now have four beautiful boys, still have my two certifications, and now attending college working towards a degree. Every day I remember lucky I am to be here and how much I have to be thankful for in life. My fiance Sean is another one of my inspirations. He stays on my case constantly about school and making sure I do what is right. I have everything I need in life to be inspired and achieve my life term goals. I believe that you need three things in life to achieve your goals, a belief system, persistence, and patience. Several things can happen to you in life. Itââ¬â¢s a matter of how you overcome what has happened and how you move forward. Although, you may want to just give up and feel you have been through enough in life and you donââ¬â¢t want to put yourself through any more. You need to reconsider, because that is just your way of ââ¬Å"justifying your thoughts or behaviorâ⬠, called rationalization which is a type of defense mechanism from Sigmund Freudââ¬â¢s psychoanalytic theory (Witt & Mossler, 2010, Ch. 2, Pg. 2). Make sure you stay focused on your goal or goals and what lies ahead of you. Always look toward the future and never look back, you will always remember but let it be a lesson learned in life, and the strength you need to move forward. There is nothing better in life than looking back on all you have been through, and then looking at what you have to this day. The best thing is looking at what lies ahead of you and your future of success! Indeed, while some may say a bad past can get the best of you, itââ¬â¢s important to stay focused and determined. I will continue to move forward with my education and become successful. Just remember one thing; you are in control of your life, your attitude, and your actions. You canââ¬â¢t change your past, but, you can change your future!
Sunday, January 5, 2020
A Genetics Definition of Homologous Chromosomes
A pair of homologous chromosomes contains chromosomes of similar length, gene position, and centromere location. Chromosomes are important molecules because they contain DNA and genetic instructions for the direction of all cell activity. They also carry genes that determine individual traits that can be inherited through reproduction. Human Karyotype A human karyotype shows the complete set of human chromosomes. Each human cells contain 23 pairs of chromosomes or 46 total. Every chromosome pair represents a set of homologous chromosomes. During sexual reproduction, one chromosome in each homologous pair is donated from the mother and the other from the father. In a karyotype, there are 22 pairs of autosomes or non-sex chromosomes and one pair of sex chromosomes. The sex chromosomes in both males (X and Y) and females (X and X) are homologs. Cellular Reproduction There are two ways that a cell can divide and reproduce and these are mitosis and meiosis. Mitosis exactly copies a cell and meiosis creates unique cells. Both of these methods of cellular reproduction are necessary for sustaining human life. Mitosis allows a zygote to replicate until a human is formed and meiosis produces the gametes that make fertilization, and therefore zygotes, possible in the first place. Mitosis Cellular division by mitosis replicates cells for repair and growth. Before mitosis begins, chromosomes are copied so that each cell produced retains the original number of chromosomes after division (this number is doubled and then halved). Homologous chromosomes replicate by forming identical copies of chromosomes called sister chromatids. After replication, single-stranded DNA becomes double-stranded and resembles the familiar X shape. As a cell further progresses through mitosis, sister chromatids are eventually separated by spindle fibers and distributed between two daughter cells. Each separated chromatid is considered a full single-stranded chromosome. The stages of mitosis are listed and explained in more detail below. Interphase: Homologous chromosomes replicate to form sister chromatids.Prophase: Sister chromatids migrate toward the center of a cell.Metaphase: Sister chromatids align with the metaphase plate at a cells center.Anaphase: Sister chromatids are separated and pulled toward opposite cell poles.Telophase: Chromosomes are separated into distinct nuclei. After the cytoplasm is divided during cytokinesis, the final stage of mitosis, two daughter cells are formed with the same number of chromosomes in each cell. Mitosis preserves the homologous chromosome number. Meiosis Meiosis is the mechanism of gamete formation that involves a two-stage division process. Prior to meiosis, homologous chromosomes replicate to form sister chromatids. In prophase I, the first stage of meiosis, sister chromatids pair up to form a tetrad. While in close proximity, homologous chromosomes exchange sections of DNA randomly in a process called crossing over. Homologous chromosomes separate during the first meiotic division and the resulting sister chromatids separate during the second division. At the end of meiosis, four distinct daughter cells are produced. Each of these is haploid and contains only half of the chromosomes of the original cell. The resulting chromosomes have the correct number of genes but different gene alleles. Meiosis guarantees genetic variation through genetic recombination via prophase crossover and random gamete fusion into diploid zygotes during fertilization. Nondisjunction and Mutations Problems occasionally arise in cell division that lead to improper cell division. These usually significantly affect the outcome of sexual reproduction whether the issues are present in gametes themselves or the cells that produce them. Nondisjunction Failure of chromosomes to separate during mitosis or meiosis is called nondisjunction. When nondisjunction occurs in the first meiotic division, homologous chromosomes remain paired. This results in two daughter cells with an extra set of chromosomes and two daughter cells with no chromosomes at all. Nondisjunction may also occur in meiosis II when sister chromatids fail to separate prior to cell division. Fertilization of these gametes produces individuals with either too many or not enough chromosomes. Nondisjunction is often fatal or otherwise results in birth defects. In trisomy nondisjunction, each cell contains an extra chromosome (for a total of 47 instead of 46). Trisomy is seen in Down syndrome where chromosome 21 has an additional whole or partial chromosome. Monosomy is a type of nondisjunction in which only one chromosome is present Sex Chromosomes Sex chromosomes can also suffer from nondisjunction. Turner syndrome is a form of monosomy that causes females to have only one X chromosome. Males with XYY syndrome have an extra Y sex chromosome in another example of trisomy. Nondisjunction in sex chromosomes typically has less severe consequences than nondisjunction in autosomal chromosomes, but still impacts the quality of life for an individual. Chromosome Mutations Chromosome mutations can affect both homologous and non-homologous chromosomes. A translocation mutation is a type of mutation in which a piece of one chromosome breaks off and is joined to another chromosome. Translocation mutation between non-homologous chromosomes is not to be confused with crossover between homologous chromosomes or regions of chromosomes. Deletion, the loss of genetic material, and duplication, the over-copying of genetic material, are other common chromosome mutations.
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