...Asexual reproduction Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only; it is reproduction which almost always does not involve meiosis, ploidy reduction, or fertilization. The offspring will be exact genetic copies of the parent, except in the specific case of automixis. A more stringent definition is agamogenesis which is reproduction without the fusion ofgametes. Asexual reproduction is the primary form of reproduction for single-celled organisms such as the archaea, bacteria, and protists. Many plants and fungi reproduce asexually as well. While all prokaryotes reproduce asexually (without the formation and fusion of gametes), mechanisms for lateral gene transfer such asconjugation, transformation and transduction are sometimes likened to sexual reproduction.[1] A complete lack of sexual reproduction is relatively rare among multicellular organisms, particularly animals. It is not entirely understood why the ability to reproduce sexually is so common among them. Current hypotheses [2] suggest that asexual reproduction may have short term benefits when rapid population growth is important or in stable environments, while sexual reproduction offers a net advantage by allowing more rapid generation of genetic diversity, allowing adaptation to changing environments. Developmental constraints[3] may underlie why few animals have relinquished sexual reproduction completely in their life-cycles...
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...Basic Processes of Reproduction Bacteria: Bacteria reproduce asexually, under positive environment settings this process is carried out through the method binary fission, where the most bacterial reproduction occurs in prokaryotic cells. The second method is through mitosis in eukaryotic cells except gametes (Pruitt & Underwood, 2006). Binary fission is asexual by nature and involves the splitting of the parent cells into two equal parts which once the split can be capable of independent existence (MediLexicon, 2004-2011). Grasshopper: Grasshoppers sexually reproduce when the male grasshopper introduces his spermatozoa through his aedeagus (reproductive organ) into the females ovipositor. The sperm sack contains a large packet of proteins known as spermatophylax that helps keep the eggs properly nourished (New World Encyclopedia, 2008). Once fertilized the female lays the eggs with her ovipositor and stomach one to two inches underground to keep them protected during the winter months until they hatch in warmer weather (New World Encyclopedia). Fish: Fish reproduce is, based on the location, time of year, and the presence of a proper mate (Pruitt & Underwood, 2006). Depending on the type of fish they gather in huge schools, and females expel eggs and the males follow behind discharging Milt (sperm) into the water. Some of the eggs float some sink to the bottom, and others are, laid in nests. Once the eggs are laid, they are commonly...
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...Ethical Implications of Assisted Reproduction The ethical implications of assisted reproduction are obvious. There is no doubt the process of assisted reproduction has caused more harm than good as massive killing of unwanted fertilized embryos are carried out during the process. Also some of the babies born through this process have some serious physical and genetic deformities that make some of their parents regret having them. Even a doctor once asserted that he did not get into assisted reproduction to help in creating severely damaged babies (Pence 88). This concern expressed by a physician shows how ethically horrendous assisted reproduction could be. Assisted reproduction has been a hotly debated issue in recent times mainly because of its ethical implications. Despite the ethical implications, assisted reproduction also has some moral, social, and religious concerns coupled with some psychological and biological or genetic implications both to the conceived embryos and their mothers. It is not an overstatement to adduce that there are disastrous health implications and consequences associated with assisted reproduction, which more often than not are overlooked by physicians and those desperate for children. There are three main types of assisted reproduction namely – artificial insemination, In Vitro Fertilization (IVF), and surrogacy. The ethical concern of these procedures is that they are unnatural method of conception, creating life in the laboratory, and fertilizing...
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...Social reproduction is broadly defined as nonprofit or profited procedures and tasks that maintain attributes of a specific social custom throughout one’s time. Primary, these tasks are usually in forms of domestic labor, child bearing, nurturing, educating one’s child and fostering individuals with disadvantages. In Barbara Cameron's Social Reproduction and Canadian Federalism, Cameron described social reproduction as two separate outlooks; “The concept includes but goes beyond physical recreation, in the sense of both biological reproduction and the daily maintenance of the current and future generation of workers” (Cameron, 45). The first outlook is the “biological reproduction”, the process of conception to childbirth, encompassing reproductive behavior, the “nonprofit procedure” and the second outlook, the “daily maintenance”—the day-by-day tasks of one’s “daily reproduction” and “profit” of life. In this assignment, I will evidently demonstrate my examples of “daily reproduction” and “profited tasks” through my eyes, as a young female adult that has not undergone “biological reproduction” or conceived. Upon recording my day-to-day activities, I have conjured up “broad range of activities, in an array of locations, which combine to ensure the daily and generational reproduction of the popluaton”(Bezanson, 24). In such, they are unpaid and my individual way of living and social contributions to the westernized population. This definition is governed and portrayed in my...
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...Animal Reproduction Reproduction is a process by which offspring is produced to continue onto the next generation. There are two types of reproduction. Asexual reproduction involves one parent and its genes, which the offspring inherits. It doesn’t need fertilization or meiosis to occur. Fission, budding, and fragmentation are the three types of asexual reproduction. Fission is when the parent separates into at least two or more individuals of the same size. The development of different independent organisms are results from current individuals is budding. The dismantling of the body into various pieces, some or all of which evolve into entirely new organisms through the redevelopment of absent body parts is fragmentation. Sexual Reproduction involves two parents of different sexes that combine their genetic information to produce an offspring. Some animals are hermaphrodites while others use parthenogenesis. Parthenogenesis is asexual reproduction that doesn’t require fertilization from males. Hermaphrodites have both male and female reproductive systems. Some hermaphrodites can inseminate themselves, while others may still need the help of the opposite sex. Animals reproduce using internal or external fertilization. Internal fertilization, used by terrestrial animals as well as whales and dolphins, occurs insides the body. The internally fertilized eggs are protected and fed while they develop inside the body. External fertilization, used by fish and amphibians, occurs outside...
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...Abstract Introduction Assissted reproduction technology (ART) can be defined as a technique that bypasses intercourse in order to follow biological pathways and manipulation of such pathways leading to pregnancy and the birth of healthy offspring(Velazquez, 2008). ART in humans has been used most effectively since the 1980’s fist concentrating on male human semen and understanding the estrous cycle of females of the same species, before long farm animal stocks were looked at. The ability to manipulate the breeding of certain genetic traits was seen as industrious, making pigs bigger, cows that produce more milk, chickens that laid more eggs and so forth.(Foote, 2002) Antonie van Leeuwenhoek and his assistant Hann were the first to discover sperm in 1678, they named them animalcules due to the sperms animated appearance and small size. Little was it known then the research and industrial and natural impact this discovery would have (REF). The first recorded western insemination was recorded in 1784 by a priest named Spallanzani who whelped 3 puppies from a dog. Much work was being done across Asia but due to lack of linguistic knowledge much of this work was unknown until a translation and review was made in 1958. By this time ART was a rapidly growing technique in the subject of this report dairy cattle(Foote, 2002). Techniques The first step is collection of semen from the male bulls. Semen is collected at a temperature between 42-45c and maintained in a water bath...
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...ETHICAL ISSUES RELATED TO REPRODUCTION Oghenebrume Pela Grand Canyon University: HLT 305 11/22/2014 Assisted reproductive technology otherwise known as fertility treatment uses various methods to achieve pregnancy. According to the CDC, the use of these methods has doubled in the last ten years. There has also been an increase in the number of successes based on the most recently collected data as at 2012. The current percentage of people born through ART (assisted reproductive technology) living in the United States is at 1% which, quite frankly, is a lot of people (Assisted Reproductive Technology (ART), 2014). In the case of surrogate parenting, an agreement is reached typically between an infertile couple and a woman who is to carry a baby for this couple. There are two main types which are gestational surrogacy and traditional surrogacy. In gestational surrogacy, conception takes place by means of IVF (in vitro fertilization) which would mean that the surrogate mother will have no genetic relationship with the resultant child. In traditional surrogacy, conception will take place either naturally or artificially which would mean that there will be a genetic relationship between the surrogate mother and the pregnancy. Sperm and egg donation as the name implies is a practice in which sperm and eggs or embryos have been donated by a third party to enable the infertile individual or couple to conceive. The donors are usually screened before they can donate and are...
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...and Mercier 1995). Even the depth at which these animals can be found varies greatly. Many species live within the intertidal zone, but a few sea cucumbers live deep in the ocean, some among hydrothermal vents (Smirnov et al. 2000). Regardless of the environment in which they are found, sea cucumbers have become highly adapted to life in that environment, especially in their reproductive cycles. Sea cucumbers can reproduce through sexual reproduction as well as asexual reproduction. Each mode of reproduction has several environmental factors that have been proposed to control its timing. This paper will first introduce the two types of reproduction found in sea cucumbers. I will then discuss some of the factors that have been shown to regulate sexual reproduction, specifically the processes of gametogenesis and spawning, and the factors assumed to control asexual reproduction. Finally, I will make a few suggestions as to directions that should be taken during future studies on external cues for reproduction in holothuroids. TYPES OF REPRODUCTION IN HOLOTHUROIDS Sexual...
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...within a particular species. Also, genetic diversity is affected by several ongoing natural issues that are related to mutation, sexual reproduction, migration, and the size of the population. The first issues that related are mutation. What is mutation? Mutation defined “an organism that has characteristics resulting from chromosomal alteration,” (www.thefreedictionary.com, 2008). The issue with mutation is that it permanently change the characteristics of the species involved in the mutation. This could lead to permanent loss of certain characteristics in a species. According to Concepts in Biology, “the Anopheles mosquito is responsible for transmitting malaria in many African countries,” (2008). The large number of people who fear that mutation can lead to disharmony in the environment. In addition, mutation is useful in determining evolutionary relationship. Second issue that related is sexual reproduction. What is sexual reproduction? According to Concepts in Biology, “the propagation of organisms involving the union of gametes from two parents," (2008). In human form the males carry sperm which are small and motile. The female carry eggs which provide food for embryo. In addition, male his sex organs main purposes are to produce the sperm and deliver it in the reproduction tract of a female. However, asexual reproduction, sexual reproduction must involve two partners. Third issue that related is migration? The issue with migration is that is changes the natural equilibrium...
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...The life of the Sperm and Egg PSY/265 The Life of a Sperm and the Life of an Egg from Start to Finish This is a story about Sammy the Sperm, and Edna the Egg. This is an exciting day for Sammy and Edna because they are going to get fertilized today. Fertilization is the moment Sammy and Edna fuse together and a new individual begins to form. Edna has been waiting for this day for 32 years, since her egg was produced when she was in the fetal ovaries, along with five million others, but today she is the chosen one! Sammy feels like he has won the lotto because he is the only one out of 500 million mobile sperm discharged today, in one ejaculation that will get to fertilize! Sammy's day; Sammy's life begins in the seminiferous tubules, inside the testes, where he has been maturing about two months. Before the great ejaculation he moves to the epididymis waiting for the great force that pushes him through the urethra. In the urethra he is mixed with a secretion from the prostate gland containing substances that facilitate his long journey to the female ovum, or Edna. First, Sammy the Sperm and the prostate secretion are discharged with immense force by the way of contractions of the pelvic muscles, and then they are followed by a sugar-containing fluid from the seminal vesicles (glands emptying into the vas deferens). From there he exits the penis into the vagina where his journey of fertilization begins. Edna's day; Edna has had a much longer life than Sammy because she...
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...Cell Reproduction The term cell reproduction refers to the process of a cell splitting to form two similar cells; this is known as cell division. Eukaryotic cells reproduce by mitosis or meiosis; and prokaryotic cells use binary fission as a means of cell reproduction. (Simon,Reece,Dickey.(2010)) Mitosis is defined as a process of asexual reproduction in which the parent cell divides in two producing a replica, with an equal number of chromosomes in a haploid cell. The product of mitosis is two diploid daughter cells. The process of mitosis creates everything accept sex cells; and occurs in all organisms. The steps of mitosis are Interphase, Prophase, Metaphase, Anaphase, Telophase and Cytokinesis. In the prophase step of mitosis the chromosomes duplicate into two sister chromatids. In metaphase the chromosomes align in the center of the cell, the spindle microtubes attach to the two sister chromatids are pulled toward the opposite poles of the cell. In anaphase the two sister chromatids separate and are considered full daughter chromosome; the mirotubes push toward opposite poles cause the cell to elongate. In telophase the chromosomes are at the far point of the opposite poles of the cell; the nucleus separates into two separate but identical daughter nuclei. In the final stage cytokinesis the cytoplasm divides forming two separate but genetically identical daughter cells. (Simon,Reece,Dickey.(2010)) Meiosis is a process of sexual reproduction which creates sex cells...
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...technology have created and given users a wider rage of ability to potentially become a photographer just by owning a smart phone. This creates a difficult field, or obstacle for those who take their photography careers seriously and are professionals. In the article, “The Work of Art in the Age of Mechanical Reproduction” by Walter Benjamin, he writes about a change in perspective in film and photography and discusses his argument towards the loss of the aura through the mechanical reproduction of art itself. He also touches upon how modern art has changed immensely since the beginning of its creation, and how it has lost a majority of its value. As social media is growing and changing, there are many opportunities for anyone to be able to take professional photos just by having equipment and the social...
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...WHAT IS CELL REPRODUCTION AND WHY IT HAPPENS According to our text book, Essentials of Biology, we begin life as a single cell but over the period of several months, we become a collection of trillions of cells. This process continues as we grow up and as we reach a fully mature adult age, old cells are replaced with new ones. Many cells divide at least once during their short life span and some divide many times before they die. This is known as cell division (parent cells and daughter cells) which are given the names of binary fission, meiosis and mitosis. New red blood cells, skin cells and digestive track cells are also generated. Reproduction is also how organisms are able to reproduce through meiosis which involves the replication of DNA and the splitting of molecules. Mitosis involves the cell division which produces two of the same identical cells from one single cell and happens as a result of a process that cells go through to form to nuclei with each of the nuclei containing the same number of chromosomes. Many eukaryotic organisms use this process for reproduction. Cells go though many cycles but all of the cycles happen in a specific event, some of which I partially mentioned above. The first in the Interphase cycle which is time it takes for a cell to perform its normal functions, depending on where it is in the human body. The next stage is the M state which includes both the division of the nucleus and the division of the cytoplasm—this is where...
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...JUDD’s Reproductions Variance Assignment 10/20/2010 To: Judd’s Reproductions’ CEO From: William Baker, Michael Derrig, Nicole Lapointe Terry Pikul, Brendan Sayers and Ryan Suerth Judd’s Reproduction prepares and sets standards for material and labor on each of its three products produced: chairs, tables and cabinets. (Refer to Schedule A). However, Judd’s does not have a formal process to compare actual results to the estimated standards and report the variances by product. Currently, Judd’s is not taking full advantage of the expected standards in terms of assessing price and quantity efficiency variances arising from the actual costs to highlight performance problems. After reviewing the company’s budgeted projections and comparing them to the actual cost of their products for January, a flexible budget (Schedule D) and variance analysis (Schedule B) was completed. Through this analysis, it has been determined that there are significant variances related to material price and quantity and labor rate and efficiency. Schedule D | | Budgeted | | Actual | | Variance | Direct Materials | | 129,300 | | 137,718 | | $ (8,418) | Direct Labor Carpenters | | 37,680 | | 32,432 | | $ 5,248 | Direct Labor Helpers | | 32,970 | | 40,637 | | $ (7,667) | Total Variance | | | | | | $(10,837) | Schedule B | | Amount | Material Price Variance | | (6,558) | Labor Rate Variance | | (4,791) | Material Quantity Variance | | (1,860) | Labor...
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...Cell Reproduction Introduction Cellular reproduction is the process by which cells duplicate their contents and then divide to yield two cells with similar, if not duplicate contents. Life as we know it depends on the ability of cells to store, retrieve and translate the genetic instructions required to make and maintain a living organism. In this assignment, I will discuss two different types of cell reproduction, mitosis and meiosis and, include the different stages required in order for the reproduction to take place. Mitosis Mitosis is a process by which a cell divides to form two daughter cells and produces an almost carbon copy of the parent cell. The daughter cells will consist of the same number and type of chromosomes as the parent cell and will be identical to each other. Although cell division is the defining characteristic of mitosis, a number of events must take place during mitosis prior to the splitting of the cell. There are four phases that constitute the period in which cells make preparation for cell division. The four phases are prophase, metaphase, anaphase and telophase. Prophase, the first stage of mitosis during which the chromosomes become shorter, thicker and consist of two chromatids. At this time, the chromosomes are still enclosed in the cell nucleus within the nuclear envelope. The chromosomes also contain a centromere, which is necessary in later phases for attachment to microtubules for migration. Late in prophase, kinetochores...
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