The effects on estrogen on invertebrates, fish are used a specific example in this paper, have been more pronounced than the effects on mammals. Estrogen has affected fish because they are directly living and developing in the contaminated waters. It would make sense that fish would have a harsher rate of feminization in a naturally occurring settings and that if estrogen concentrations became too high then land animals would start to show feminization in the wild.
Many kinds of fish are ideal for estrogen effect experiments because they have a quick life span. Also, since the fish are living directly in the water they are the biggest population affected by estrogen. Researchers Kidd, Blanchfield, Mills, Palace, Evans, Lazorchak and Flick (2007) had done a 7 year whole-lake experiment at Experimental Lakes Area (ELA) in northwestern Ontario, Canada. They studied how chronic exposure to 17α-ethynylestradiol at concentrations of 5–6 ng•L−1 to the fathead minnow (Pimephales promela) would affect the minnow. Over the 7 years they checked the minnows periodically, after 7 weeks and after 3 years and so on, and the results were the male minnows had an elevated level of vitellogenin. And the level of vitellogenin was higher than seen in reference females exposed to the same conditions. Vitellogenin is a precursor protein found in egg yolks expressed in the females in species of fish and most invertebrates. The presence of vitellogenin in males is a form of feminization because if enough estrogen is present the Vg gene will express. The Vg gene expression is induced by estrogen dependent activity and in normal males estrogen levels are too low to induce vitellogenesis. The expression of the Vg gene can also be used as molecular marker f...
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...eminization. Journal of Applied Ichthyology. [Cited 22 March 2011]23(1), 3-8. Available from: doi:10.1111/j.1439-0426.2006.00819.x
Tyler CR, Jobling S. 2008. Roach, Sex, and Gender-Bending Chemicals: The Feminization of Wild Fish in English Rivers. BioScience.[Cited 22 March 2011] 58(11), 1051-1059. Available from: doi:10.1641/B581108
Liney KE, Hagger JA, Tyler CR, Depledge MH, Galloway TS, Jobling S. 2006. Health Effects I n Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works. Environmental Health Perspectives. [Cited 22 March 2011] 11481-89. Available from: doi:10.1289/ehp.8058
Environmental Protection Agency. 2010. Downstream without hormones: Can rabbit food solve an emerging environmental problem? [Cited 22 November 2011] Available from: Environmental Pollution: http://www.epa.gov/ord/sciencematters/august2011/rabbitfood.htm
The New England Journal of Medicine -- February 1, 1996 -- Vol. 334, No. 5
In the early development process of many organisms, it is important to be able to minimize exposure to agents of stunted or arrested development. By decreasing the mortality rate for a generation of a species, that species is given an advantage in later reproduction; by increasing the number of organisms of the same species within a limited environment, more organisms of the same species are able to reproduce, resulting in an augmented overall population ("Reproduction and Development", 2013). However, when toxins are introduced to an environment, an embryo’s viability can decrease. Mortality rates for the generation of the species can increase, and defects that are harmful to the reproductive cycle can emerge. Thus, it is necessary to measure and observe the effects of certain toxins on embryonic development. The North American brine shrimp, or Artemia Franciscana (Artemia Salina), is subject to changes in its environment. Toxins introduced to its hatching environment, such as ethanol (in concentrations of 0.1%, 0.15%, and 0.2%), can have significant impact for the hatching process and embryonic development. The experiment sought to explore the relationship between birth defects and exposure to ethanol at early developmental stages through the use of American brine shrimp. However, to be able to fully comprehend the impact that certain toxins would have on the embryonic development of the North American brine shrimp, it is first important to be versed in its specific hatching process.
The scientists are concerned with the hormones use and their impact of the environment. The scientists are also concerned with the hormones being excreted in the manure. The scientists say, that the hormones that are going into the can be found in the soil and the water supply.(Communication Foundation) The scientists also say that the hormones being used are affecting human development through the human reproductive system.
The Kaleidoscope of Gender: Prisms, Patterns, and Possibilities written by Joan Z. Spade and Catherine G. Valentine is a book about the sociology of gender and the construct thereof. The writers use a metaphor of a kaleidoscope to illustrate their interpretations of the topic. A kaleidoscope is a toy consisting of a tube containing mirrors and pieces of colored glass or paper, whose reflections produce changing patterns that are visible through an eyehole when the tube is rotated. Utilizing the similitude of the kaleidoscope, this collection presents gender as a result of always transforming patterns get under way by prisms that underlie change, both straightforward and complex, bringing about an extensive variety of possibilities. The book
Gender Matters is a collection of various essays on feminist linguistic texts analysis, by Sara Mills. Mills develops methods of analyzing literary and non-literary texts, in addition to conversational analysis based on a feminist approach. The author draws on data from her collection of essays gathered over the last two decades on feminism during the 1990s. The essays focus on gender issues, the representation of gender in reading, writing, and in public speaking. Furthermore, it highlights the importance of feminists’ analysis of sexism in literature and the relation between gender and politeness. The article is informative for my research paper, as my topic is going to cover language analysis of the text and who women reading and writing differs according to the discourse analysis within linguistic, psychology, case studies audiences and surveys. The book would be helpful, particularly the last three essays that discusses gender, public speaking, the question of politeness and impoliteness in public speaking. Mills’ analysis is not complete without including the idea of global notions of both women and men, to see whether women and men write and read in the same way globally. Therefore, an update would enrich the book’s discussion section. Although, Mills addresses the class and race theme in language and public speaking, I will only look into the role of language that plays a part in doing or reducing gender in literary, non-literary texts and in conversation.
Chatterjee, A. (2009). A medical view of potential adverse effects. Nature, 457(7229), 532-533. Retrieved from EBSCOhost.
Darwin's theory of sexual selection is an intriguing one because it offers an explanation of human striving and cultural value systems. The theory is that humans who are more sexually desirable will have more offspring and thus their traits will be passed on to future generations to a greater extent than those of less sexually desirable humans. As opposed to Darwin's other theory, natural selection, those who are the best adapted to their environment will be more likely to pass on their genes, or, "survival of the fittest", you might call sexual selection "survival of the sexiest." The theory is intended to in part explain why, when humans diverged from other primates, the human brain tripled in size in just two million years. At first glance, this theory also seems to explain much of the motivation behind human culture and achievement. Upon closer inspection, there are some fairly conspicuous problems with it, especially when it is extended to describe not only human evolution in the distant past but it the present, but it may still be the most plausible explanation available to explain why humans mental capacities have expanded so far beyond those of our primate relatives.
Chemical pollution into the environment can cause both genotypic and phenotypic changes in many organisms, including humans. More specifically, environmental pollutants like BPA can act as xenoestrogens (estrogen imitators), ultimately affecting hormonal activity and production in an organism. This alteration in activity and production can be termed as endocrine disruption. The endocrine system regulates a variety of processes responsible for growth and development, including gonadal formation and function, digestion, metabolism, sex differentiation, and embryonic development (reviewed by Flint et al., 2012). Chemicals that interfere with the function or structure of the endocrine system can be defined as endocrine disrupting compounds (EDCs) (US Environmental Protection Agency, 2007).
Evidence provided to support these claims of human and wildlife harm is largely from laboratory studies in which large doses are fed to test animals, usually rats or mice, and field studies of wildlife species that have been exposed to the chemicals mentioned above. In laboratory studies, high doses are required to give weak hormone activity. These doses are not likely to be encountered in the environment. However the process of bioaccumulation can result in top-level predators such as humans to have contaminants at levels many million times greater than the environmental background levels (Guilette 1994). In field studies, toxicity caused by endocrine disruption has been associated with the presence of certain pollutants. Findings from such studies include: reproductive disruption in starfish due to PCBs, bird eggshell thinning due to DDT, reproductive failure in mink, small penises in alligators due to DDT and dicofol (Guillette 1994, Colburn et al 1996). In addition, a variety of reproductive problems in many other species are claimed to be associated with environmental contamination although the specific causative agents have not been determined. One recent discovery that complicates the situation is that there are many naturally occurring "phytoestrogens", or chemicals of plant origin that exhibit weak estrogenic properties.
The male reproductive system is a set of organs that works together to produce sperm which will later in life fertilize females eggs. The testes are the most important part of the system because it produces sperm cells. It is similar and looks similar to ovaries of a female’s reproductive system because it also holds what they need to reproduce. Its job is to produce the sperm cells needed to reproduce. Due to hormonal imbalances the production of sperm cells may not even be possible in some males. Testosterone is the male the hormone that gives men there manly characteristics. It is made up of hydrogen, carbon, and oxygen with a white color. In the male body it helps develop sex organs, a deeper voice, and facial hair (Khalid, 2013). Cancer or a genetic disorder in males is the most common thing that cause the reductions of testosterone production in the body. Behind the testes is the epididymis which lets sperm go through the vas deferens from the testes (Dictionary, 2014). It looks like leach the way it is position right on the testes but it is thinner. When sperm is produces the ...
The reproductive systems are based off of the goal to create offspring. Both the male and the female reproductive systems, although fueled by a similar goal, have different components and structures. Both systems are very complex in their own way, making it important for one to understand how each of the systems and their various processes work. Knowing the processes and components of the male and female reproductive systems will aid all people in their life, sometime or another. It’s important to understand how our individual bodies work and how life is produced.
Sex Selection is usually thought of as a procedure that occurs prior to conception, however, that is not always the case. Sex selection is a method that is used prior to and after conception. Focusing on after conception and birth, sex selection can take place by genetically testing, or by taking ultrasound images of the developing fetus, resulting in abortion due to an undesired gender. The practice of sex selection can also take place after birth of the child, “[…] when one or both parents kill their baby” (Dixon).
Unlike most organ systems in the human body, the reproductive system seems to snooze until the individual hits puberty (Marieb & Hoehn, 2013) – when the system reveals its true purpose: sexual reproduction. In the female reproductive system, the primary sex organs, also known as gonads, are the ovaries. The ovaries produces gametes: ova, which are homologous to the sperm produced by the male’s reproductive system. The female internal sex organs include the ovaries and the duct system. The duct system’s accessory ducts are the uterine tubes, the uterus, and the vagina – these are connected from the ovaries to the external genitalia. Ovaries also produce steroid sex hormones: estrogens and progesterone. These hormones have roles in the development and function of the reproductive organs, sexual behavior and drives, and the growth and development of many other organs and tissues. Specifically,
Oroian, Viman Oana I. "Damaging Effects of Overall Water Pollution." BioFlux (2010): 113-15. Web. 16 Apr. 2014.
One of the major biological differences between males and females are hormones. Hormones that were once thought to only be important for pregnancy and sexual drive are now shown to have profound effects on just about every organ in the body.(*) Some researchers believe that higher exposure to estrogen, in females, or androgens, in males, during fetal development not only causes the sex organs to form but also predisposes the infant to behavior that is typically associated with one gender or the other. (*) For example, girls that were exposed to higher than normal prenatal levels of androgens were more likely than other females to engage in “boy-like” behavior and to play with boy’s toys eve...