Mendelian genetics essay

According to this Mendelian concept, inheritance of a trait depends on the passing-on of these units. For any given trait, an individual inherits one gene from each parent so that the individual has a pairing of two genes. If the two alleles that form the pair for a trait are identical, then the individual is said to be homozygous and if the two genes are different, then the individual is heterozygous for the trait. Based on his pea plant studies, Mendel proposed that traits are always controlled by single genes.

Mendelian genetics essay

Francis Galton, who coined the term eugenics inperceived it as a moral philosophy to improve humanity by encouraging the ablest and healthiest people to have more children. The Galtonian ideal of eugenics is usually termed positive eugenics.

Negative eugenics, on the other hand, advocated culling the least able from the breeding population to preserve humanity's fitness. The eugenics movements in the United States, Germany, and Scandinavia favored the negative approach.

The notion of segregating people considered unfit to reproduce dates back to antiquity. For example, the Old Testament describes the Amalekites — a supposedly depraved group that God condemned to death.

Concerns about environmental influences that Mendelian genetics essay damage heredity — leading to ill health, early death, insanity, and defective offspring — were formalized in the early s as degeneracy theory. Degeneracy theory maintained a strong scientific following until late in the 19th century.

Masturbation, then called onanism, was presented in medical schools as the first biological theory of the cause of degeneracy. Fear of degeneracy through masturbation led Harry Clay Sharp, a prison physician in Jeffersonville, Indiana, to carry out vasectomies on prisoners beginning in The advocacy of Sharp and his medical colleagues, culminated in an Indiana law mandating compulsory sterilization of "degenerates.

By the midth century most scientists believed bad environments caused Mendelian genetics essay heredity. Benedict Morel's work extended the causes of degeneracy to some legitimate agents — including poisoning by mercury, ergot, and other toxic substances in the environment.

The sociologist Richard Dugdale believed that good environments could transform degenerates into worthy citizens within three generations. This position was a backdrop to his very influential study on The Jukesa degenerate family of paupers and petty criminals in Ulster County, New York.

The inheritance of acquired environmental characters was challenged in the s by August Weismann, whose theory of the germ plasm convinced most scientists that changes in body tissue the soma had little or no effect on reproductive tissue the germ plasm.

AP Biology Essay Questions The following is a comprehensive list of essay questions that have been asked on past AP exams. The questions are organized according to units. Unit 1 (Basic Chemistry and Water) 1. The unique properties (characteristics) of water make life possible on Earth. Select three properties of water and: for each property, . Genes (ISSN ; CODEN: GENEG9) is a peer-reviewed open access journal of genetics and genomics published monthly online by MDPI.. Open Access Free for readers, with article processing charges (APC) paid by authors or their institutions.; High visibility: Covered by Science Citation Index Expanded (Web of Science) and Scopus. Citations are available in PubMed, full-text archived in. Pearson, as an active contributor to the biology learning community, is pleased to provide free access to the Classic edition of The Biology Place to all educators and their students.

At the beginning of the 20th century, Weismann's views were absorbed by degeneracy theorists who embraced negative eugenics as their favored model. Adherents of the new field of genetics were ambivalent about eugenics. Most basic scientists — including William Bateson in Great Britain, and Thomas Hunt Morgan in the United States — shunned eugenics as vulgar and an unproductive field for research.

Mendelian genetics essay

However, Bateson's and Morgan's contributions to basic genetics were quickly absorbed by eugenicists, who took interest in Mendelian analysis of pedigrees of humans, plants, and animals.

Many eugenicists had some type of agricultural background. Charles Davenport and Harry Laughlin, who together ran the Eugenics Record Office, were introduced through their shared interest in chicken breeding.

The Science of Human Improvement through Better Breeding, had a distinct agricultural flavor, and his affiliation with the ABA was included under his name on the title page.

Agricultural genetics also provided the favored model for negative eugenics: Evolutionary models of natural selection and dysgenic bad hereditary practices in society also contributed to eugenic theory.

For example, there was fear that highly intelligent people would have smaller families about 2 childrenwhile the allegedly degenerate elements of society were having larger families of four to eight children.

Public welfare might also play a role in allowing less fit people to survive and reproduce, further upsetting the natural selection of fitter people. Medicine also put its stamp on eugenics.

Reality Club Discussion

Physicians like Anton Ochsner and Harry Sharp were convinced that social failure was a medical problem. Italian criminologist and physician Cesare Lombroso popularized the image of an innate criminal type that was thought to be a reversion or atavism of a bestial ancestor of humanity.

When medical means failed to help the psychotic, the retarded, the pauper, and the vagrant, eugenicists shifted to preventive medicine. The German physician-legislator Rudolph Virchow, advocated programs to deal with disease prevention on a large scale.

Virchow's public health movement was fused with eugenics to form the racial hygiene movement in Germany — and came to America through physicians he trained. Eugenicists argued that "defectives" should be prevented from breeding, through custody in asylums or compulsory sterilization.

Most doctors probably felt that sterilization was a more humane way of dealing with people who could not help themselves. Vasectomy and tubal ligation were favored methods, because they did not alter the physiological and psychological contribution of the reproductive organs.

Sterilization allowed the convicted criminal or mental patient to participate in society, rather than being institutionalized at public expense. Sterilization was not viewed as a punishment because these doctors believed erroneously that the social failure of "unfit" people was due to an irreversibly degenerate germ plasm.Critic ignores reality of Genetic Entropy The author of a landmark book on genomic decay responds to unsustainable criticisms.

by Dr John Sanford. Published: 7 March (GMT+10). Mendelian Genetics Heredity is the passing of genetics from your parents to you. The characteristics you have resemble the characteristics that your parents have.

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The characteristics you have resemble the characteristics that your parents have. The unifying theme for much of modern biology is based on Charles Darwin’s theory of evolution, the process of natural selection by which nature selects the fittest, best-adapted organisms to reproduce, multiply and survive. has been an NCCRS member since October The mission of is to make education accessible to everyone, everywhere. Students can save on their education by taking the online, self-paced courses and earn widely transferable college credit recommendations for a fraction of the cost of a traditional course.

Free Essay: Lab Report: Mendelian Genetics Introduction: In an Austrian monk, Gregor Mendel, presented the results of painstaking experiments on the. Emerging in the 's, Mendelian genetics dominated the beliefs of the scientific and the general public regarding the theories of intelligence in relation to success in life (Jensen, ; Shenk, ).


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