Wednesday, November 27, 2019
Genetic Research Must be Regul essays
Genetic Research Must be Regul essays Human genetics and cloning have become a subject of hot debate in the recent past. Currently there are very few restrictions or regulations on genetic research and cloning. This means that the world of genetic research is wide open. In order to control genetic research and cloning an official government run department or committee must be established. This department would be able to regulate and restrict all genetic research and set a standard in bioethics. The most important duty of the government department of bioethics would be to set guidelines for what is and is not acceptable in genetics research. This department or committee would decide what kind of research and experiments would be permissible. This would prevent experiments such as the Tuskegee Syphilis Experiment from happening again in the future. With few laws in effect right now, just about anyone can perform any experiment they want with genetics. This presents a great danger that morbid and inhuman experiments could be performed with no repercussions. An official committee would be able to control such research by enacting laws and prosecuting the perpetrators. The second function of an official government body would be to answer all of the ethical questions about genetic research. One question that this group would answer is after a person is tested genetically, who should have access to the results of the test? This question brings about a lot of controversy, especially if the person tested is found to have some kind of genetic disposition to a certain disease. Should insurance companies or employers be given this information? If insurance companies were notified, surely they would raise the premium or drop the coverage of the high-risk client. An employer may let their employee go if they know he or she may be getting ill sometime in the future and will not be able to perform as he or she did in the past. This ...
Saturday, November 23, 2019
7 Department of Labor rules every intern should know
7 Department of Labor rules every intern should know Attention current and future interns! We know that this is an exciting time for you. Youââ¬â¢re about to embark on the early stages of your professional careers- a journey that for most of us makes up a significant portion of our adult lives and contributes greatly to our sense of self, happiness, and fulfillment. Internships are great opportunities for you to begin figuring out your strengths and weaknesses, likes and dislikes, interests and passions, and can really help guide you toward what you want to do with your work life. Yes, itââ¬â¢s an exciting time of personal exploration and discovery- but that doesnââ¬â¢t mean you should blindly race forward without knowing a few things first. Understanding some of the basic rules regarding internships- including your rights as an unpaid intern or paid employee- will help ensure that your work experience is as productive and impactful as possible, and that your hard work and efforts are rightfully respected and rewarded.The U.S. Department of Labor, in an effort to protect the rights of interns and employees across industries and job positions, have established regulations under the Fair Labor Standards Act (FLSA) to determine if the nature of the work an individual is performing qualifies them as an unpaid intern or an actual employee- which means that they qualify for FLSA employee protections and benefits, such as a minimum wage and overtime pay. In order to determine whether an intern or student is actually an employee, the FLSA lists the following seven factors to consider:1. The extent to which the intern and the employer clearly understand that there is no expectation of compensation. Any promise of compensation, express or implied, suggests that the intern is an employee- and vice versa.2. The extent to which the internship provides training that would be similar to that which would be given in an educational environment, including the clinical and other hands-on training provided by educational in stitutions.3. The extent to which the internship is tied to the internââ¬â¢s formal education program by integrated coursework or the receipt of academic credit.4. The extent to which the internship accommodates the internââ¬â¢s academic commitments by corresponding to the academic calendar.5. The extent to which the internshipââ¬â¢s duration is limited to the period in which the internship provides the intern with beneficial learning.6. The extent to which the internââ¬â¢s work complements, rather than displaces, the work of paid employees while providing significant educational benefits to the intern.7. The extent to which the intern and the employer understand that the internship is conducted without entitlement to a paid job at the conclusion of the internship.Once you determine if your position falls under the category of an unpaid internship or actual employment, you can then determine what rights youââ¬â¢re entitled to- either as an intern or as an employee. Ke ep in mind that your basic rights are also protected in the workplace, which includes your right to a safe environment thatââ¬â¢s free from discrimination and harassment of all types. If you ever have any questions or concerns regarding your rights, either contact the HR department of the company youââ¬â¢re working for or speak to a parent, trusted friend, or mentor.If youââ¬â¢re about to start an internship, you should first know your rights in the workplace, to help ensure that you have a great experience. Use the information provided here, along with the United States Department of Laborââ¬â¢s website, to get informed and prepared for your first day on the job. Good luck!
Thursday, November 21, 2019
Psychological profile on Hannibal lector and Buffalo Bill Essay
Psychological profile on Hannibal lector and Buffalo Bill - Essay Example Nevertheless, based on first hand information gathered by the authors biographer David Sexton, it is learnt that the character of Hannibal Lecter was based on that of William Coyne, a notorious serial killer who terrorized American society in the 1930s. In this context, one can claim that Lecters profile belongs to the Psychopath category. This assessment also makes sense when one considers the childhood history of Lecter. It should be noted that the novel The Silence of the Lambs does not delve into his childhood history. It is the fourth and fifth books of the sequel, namely Hannibal and Hannibal Rising, that provide greater detail about his early life. Nevertheless, since the underlying theme and the authorship of all these books are the same, one can arrive at the approximate profile of Lecter by cross referencing material from these novels and films. Although the brilliance of his mind was evident from the beginning and something that he was born with, his anti-social tendencies developed as a result of severely traumatic experiences in the past. In his early years in Lithuania, he witnessed the traumatic death and consumption of his sister Mischa, whom he had loved very much. This incident had left profound would on his psyche, which would turn him into a remorseless, cannibalistic psychopath. The adage ââ¬Å"take the help of a thief to catch a thiefâ⬠fits so aptly in the case of psychopaths as well. In the movie The Silence of the Lambs, Clarice Starling, a rookie FBI trainee, takes the help of Hannibal Lecter, who is in police custody, to identify and track down another serial killer with the name ââ¬Å"Buffalo Billâ⬠. While both Lecter and Buffalo Bill are psychopathic serial killers, the latter seems to be more indiscriminate and brutal in performing his crimes. The other distinction between the two is that Buffalo Bill is not shown to be cannibalistic, but Lecter clearly is. Buffalo Bill, whose real name is Jame
Tuesday, November 19, 2019
_Management_and_Organisations Essay Example | Topics and Well Written Essays - 1000 words
_Management_and_Organisations - Essay Example According to Robins and Judge (2011, p. 488), organizational structure refers to a specific pattern in which job tasks are formally grouped, divided and categorized and accordingly coordinated. Division of labor, coordination, communication and workflow etc are influenced by the structure of the organization. Organizations are structured in different ways such as flexible firm, the boundary-less organization, the lean organization, the down-sized organization, empowerment, outsourcing, networking and the virtual organization (Needle, 2010, p. 188). Marks and Spencer has previously layered its organization into several groups and thus considered an elaborate structure, but has recently eliminated a number of layers through the process of de-layering and adopted ââ¬Ëflat organizational structureââ¬â¢. A flat organization structure is a form of organization with relatively few layers of management and is less bureaucratic (DuBrin, 2011, p. 274). Flat organization structure combine s a number of elements such as low degree of job specialization, loose departmentalization, few levels of management, wider control span, decentralized decision-making and shorter chain of command (Gitman and McDaniel, 2008, p. 190). Marks and Spencer recently reduced many numbers management layers resulting that employees have more responsibility for everything they do. A significant result of flat organization is that remaining managers become highly responsible with larger span of control with more numbers of employees reporting to a particular manager. The Economic situation of Marks and Spencer Marks and Spencer operates more than 700 stores across the UK and more than 400 stores in around 44 countries across the Europe, Middle East and Asia (Corporate.marksandspencer.com, 2013). Out of its stores in the UK, around 350 stores are department stores that sell mid-priced apparel, food and household items under the M&S private label brands, including Autograph, Classic and Portfoli o. About 90 percent of its total revenues and profits derive from its home country- UK. Marks and Spencer is the market leader of women-wear, lingerie and menswear. Its market is rigorously competitive as it faces extremely fierce competition from its market players such as Tesco, Next Plc and Asda Plc. Marks and Spencer is a public limited company that sells medium-prices clothes, apparel, and food and home products. Since the 2008 economic downturn, the UK market place was turbulent as UKââ¬â¢s Gross Domestic Product in recent years was revised down, and the government faced difficult to tackle the deficit. Consumers across the UK have relatively better understanding of how to manage their household and spending in difficult times. Marks and Spencer, considering consumersââ¬â¢ concern about spending, implemented certain strategic steps such as promotions, and has found significant rise in its total revenues (Annual Report, 2012). Some factors like quality, value, longevity a nd versatility impacted the general responses to products and services offered by marks and Spencer in recent years. Consumers were found to continually invest in certain staple items looking for products that have longevity and ver
Sunday, November 17, 2019
Life of John Milton Essay Example for Free
Life of John Milton Essay Milton continued to write poetry during this period of study: his Arcades and Comus were both commissioned for masques composed for noble patrons, connections of the Egerton family, and performed in 1632 and 1634 respectively. Comus argues for the virtuousness of temperance and chastity. He contributed his pastoral elegy Lycidas to a memorial collection for one of his Cambridge classmates. Drafts of these poems are preserved in Miltonââ¬â¢s poetry notebook, known as the Trinity Manuscript because it is now kept at Trinity College, Cambridge. Family Milton and his first wife, Mary Powell (1625ââ¬â1652) had four children: * Anne (born 7 July 1646) * Mary (born 25 October 1648) * John (16 March 1651 ââ¬â June 1652) * Deborah (2 May 1652 ââ¬â ?) Mary Powell died on 5 May 1652 from complications following Deborahs birth. Miltons daughters survived to adulthood, but he had always a strained relationship with them. On 12 November 1656, Milton was married again, to Katherine Woodcock. She died on 3 February 1658, less than four months after giving birth to a daughter, Katherine, who also died. Milton married for a third time on 24 February 1662, to Elizabeth Mynshull (1638ââ¬â1728), the niece of Thomas Mynshull, a wealthy apothecary and philanthropist in Manchester. Despite a 31-year age gap, the marriage seemed happy, according to John Aubrey, and was to last more than 11 years until Miltons death. (A plaque on the wall of Mynshulls House in Manchester describes Elizabeth as Miltons 3rd and Best wife.) Two nephews, John Phillips and Edward Phillips, were well known as writers. They were sons of Miltons sister Anne. John acted as a secretary, and Edward was Miltons first biographer. Blindness But in the course of his work for the government, his eyesight had begun to fail, and by 1651 (43) he was completely blind. Death He ended his days in a small house near Bunhill Fields, alone with his wife and a maid. He died in ++1674 (66) without pain or emotion, according to testimony at the time no one in the room noticing his passing. - Published poetry Milton is the author of dramas such as Samson Agonistes (1671) as well as lyrical sonnets, of which the finest were in fact inspired the the death of his second wife. Altogether John Milton would write twenty- three sonnets. In a very real sense therefore these can be considered as exceptions. He uses such moments to express his thoughts and feelings on specific events, historical or personal. In his lifetime, moreover, he was mainly known for his political pamphlets. As a poet during the age of Shakespeare, he was born less than a decade after the death of this one. Milton might have been less appealing than such a master of the English language but he was nonetheless destined to become one of the best writers England would ever know. Having sided with the parliamentarians against the monarchists, Milton would begin a political career with responsibilities comparable to that today of an undersecretary of state for foreign affairs. However the restoration of the monarchy in 1660 will mean that he is both fined and imprisoned in the famous still standing today Tower of London. Eventually pardoned, Milton would from then on lead a rather retired life devoted entirely to writing until his death in 1674. Miltons poetry was slow to see the light of day, at least under his name. His first published poem was On Shakespear (1630), anonymously included in the Second Folio edition of Shakespeare. In the midst of the excitement attending the possibility of establishing a new English government, Milton collected his work in 1645 Poems. The anonymous edition of Comus was published in 1637, and the publication of Lycidas in 1638 in Justa Edouardo King Naufrago was signed J. M. Otherwise the 1645 collection was the only poetry of his to see print, until Paradise Lost appeared in 1667. Paradise Lost Main article: Paradise Lost Miltonââ¬â¢s magnum opus, the blank-verse epic poem Paradise Lost, was composed by the blind and impoverished Milton from 1658 to 1664 (first edition) with small but significant revisions published in 1674 (second edition). As a blind poet, Milton dictated his verse to a series of aides in his employ. It reflects his personal despair at the failure of the Revolution, yet affirms an ultimate optimism in human potential. Milton encoded many references to his unyielding support for the Good Old Cause.[31] Milton followed up Paradise Lost with its sequel, Paradise Regained, published alongside the tragedy Samson Agonistes, in 1671. Both these works also resonate with Miltonââ¬â¢s post-Restoration political situation. Just before his death in 1674, Milton supervised a second edition of Paradise Lost, accompanied by an explanation of why the poem rhymes not and prefatory verses by Marvell. Milton republished his 1645 Poems in 1673, as well a collection of his letters and the Latin pr olusions from his Cambridge days. A 1668 edition of Paradise Lost, reported to have been Miltons personal copy, is now housed in the archives of theUniversity of Western Ontario. Paradise Lost is an epic poem in blank verse by the 17th-century English poet John Milton. It was originally published in 1667 in ten books, with a total of over ten thousand individual lines of verse. A second edition followed in 1674, changed into twelve books (in the manner of the division of Virgils Aeneid) with minor revisions throughout and a note on the versification.[1] The poem concerns the Biblical story of the Fall of Man: the temptation of Adam and Eveby the fallen angel Satan and their expulsion from the Garden of Eden. Miltons purpose, stated in Book I, is to justify the ways of God to men.[2] Paradise Lost is widely considered one of the greatest literary works in the English language.[3] The poem begins strong as follows: Of Mans first disobedience, and the fruit of that forbidden tree, whose mortal taste brought death into the world, and all our woe (with loss of Eden, till one greater Man restore us, and regain the blissful seat) Some of the famous verses from Paradise Lost include: The mind is its own place, and in itself Can make a heavââ¬â¢n of hell, a hell of heavââ¬â¢n. The context of this passage is that of Satan not yet really considering revenge. At that point he is instead deciding to make the most of the situation. This is confirmed only a few lines later when he makes the very famous utterance: Better to reign in hell, than serve in heavââ¬â¢n. The following quote is from a point in the work when God is talking with his son and angels about the fact that since angels and man were given free will, it would have been meant changing their nature to have intervened and prevented their sin: The first sort by their own suggestions fell, Self-tempted, self-depraved: man falls deceived By the other first: man therefore shall find grace, The other none Finally, let us consider the following quote where Milton tells us about Eve having been deceived: Greedily she engorged without restraint, And knew not eating death; It interesting to note that even though Paradise Lost was to become considered as a major influential work, it did not meet immediate success when it was first published in 1667. It was not until 1688, a little over ten years after Miltonââ¬â¢s death that the poem would start to be widely recognized. Perhaps such late recognition has partly to do with the fact that by the time of his death Milton was not only broke, but he had been alienated out of intellectual life in his own country. In 1670 he would publish his controversial The History of Britain, and in 1671 Paradise Regained, dealing with the temptation of Christ. Milton would die in London on November 8 1674. The same year would appear the second edition of Paradise Lost. - Characters Satan Satan is the first major character introduced in the poem. Formerly the most beautiful of all angels in Heaven, hes a tragic figure who describes himself with the now-famous quote Better to reign in Hell than to serve in Heaven. He is introduced to Hell after he leads a failed rebellion to wrestle control of Heaven from God. Satans desire to rebel against his creator stems from his unwillingness to be subjugated by God and his Son, claiming that angels are self-begot, self-raised,[4] thereby denying Gods authority over them as their creator. Adam Adam is the first human created by God. Though initially alone, Adam demands a mate from God. Considered Gods prized creation, Adam, along with his wife, rules over all the creatures of the world and reside in the Garden of Eden. He is more intelligent and curious about external ideas than Eve. He is completely infatuated with Eve, which while pure in and of itself, eventually contributes to his reasons for joining Eve in disobedience to God. Eve Eve is the second human created by God, taken from one of Adams ribs and shaped into a female form of Adam. In her innocence, she is the model of a good wife, graceful and submissive to Adam. Though happy, she longs for knowledge and, more specifically, self-knowledge. Her first act in existence is to turn away from Adam and look at and ponder her own reflection. Eve is extremely beautiful and thoroughly in love with Adam, though may feel suffocated by his constant presence. One day, she convinces Adam that it would be good for them to split up and work different parts of the Garden. In her solitude, she is tempted by Satan to sin against God. Adam shortly follows along with her. The Son of God The Son of God is the spirit that will become Jesus Christ, though he is never named explicitly, since he has not yet entered human form. The Son of God shares total union with God, and indeed is understood to be a person of the Godhead, along with the Father and the Spirit. He is the ultimate hero of the epic and infinitely powerful, singlehandedly defeating Satan and his followers when they violently rebel against God and driving them into Hell. The Son of God tells Adam and Eve about Gods judgment after their sin. However, he sacrificially volunteers to eventually journey to the World, become a man himself, and redeem the Fall of Man through his own death and resurrection. In the final scene, a vision of Salvation through the Son of God is revealed to Adam by Michael. Still, the name, Jesus of Nazareth, and the details of Jesus story are not depicted in the poem.[7] God the Father God the Father is the creator of Heaven, Hell, the World, and of everyone and everything there is. He desires glory and praise from all his creations. He is an all-powerful, all-knowing, infinitely good being who cannot be overthrown by even the great army of angels Satan incites against him. The poem begins with the purpose of justifying the ways of God to men, so God often converses with the Son of God concerning his plans and reveals his motives regarding his actions. The poem portrays Godââ¬â¢s process of creation in the way that Milton believed it was done, that God created Heaven, Earth, Hell, and all the creatures that inhabit these separate planes from part of Himself, not out of nothing.[8] Thus, according to Milton, the ultimate authority of God derives from his being the author of creation. Satan tries to justify his rebellion by denying this aspect of God and claiming self-creation, but he admits to himself this is not the case, and that God deserved no such return/ Fr om me, whom He created what I was.[9][10] Raphael Raphael is an angel who is sent by God to warn Adam about Satans infiltration of Eden and to warn him that Satan is going to try to curse Adam and Eve. He also has a lengthy discussion with the curious Adam regarding creation and events which transpired in Heaven. Michael Michael is a mighty archangel who fought for God in the Angelic War. In the first battle, he wounds Satan terribly with a powerful sword that God designed to even cut through the substance of angels. After Adam and Eve disobey God by eating from the Tree of Knowledge, God sends the angel Michael to visit Adam and Eve. His duty is to escort Adam and Eve out of Paradise. But before this happens, Michael shows Adam visions of the future which cover an outline of the Bible, from the story of Cain and Abel in Genesis, up through the story of Jesus Christ in the New Testament. Interpretation and criticism The Creation of Man, engraving from the 1688 edition, by John Baptist Medina The writer and critic Samuel Johnson wrote that Paradise Lost shows off [Miltons] peculiar power to astonish and that [Milton] seems to have been well acquainted with his own genius, and to know what it was that Nature had bestowed upon him more bountifully than upon others: the power of displaying the vast, illuminating the splendid, enforcing the awful, darkening the gloomy, and aggravating the dreadful.
Thursday, November 14, 2019
Dwight D Eisenhower Essay -- essays research papers
He was born in a small town called Deniso in western Texas in the year 1890 (Hargrove 22).Then he and his family moved to a railroad town called Abilene in the state of Kansas. Here Dwight Eisenhower grew upwith his 13 other family members. (Hargrove 19). Dwight David Eisenhower is one of Americas greatest heroes with his military career to his two terms as President of the United States. Dwight Eisenhower had many accomplishments to and from West Point through World War One. Ike Eisenhower wanted to serve his country in any way he could. He found the idea of being a sailor in the U.S Navy intriguing, but when he later applied for entering he found that he was too old at the age of 20. Then after studying hard Eisenhower was accepted atthe West Point Military Academy with the help of a U.S senator (Hargrove33). At college Ike showed himself as a hero on the Army Football team asan end (Hargrove 34). He also found an easier procedure for working advanced calculus (Hargrove 36). At the end of his college career in 1915,Eisenhower graduated number 61 out of a class of 164 (Hargrove 38). Eisenhower's military journey began during World War One. When he graduated college World War One was still raging through Europe. Instead of fighting in the infantry overseas Eisenhower was to stay home on U.Sbases (Hargrove 41). After being promoted to a Lieutenant Colonel, Eisenhower was sent to Camp Colt to train soldiers about tanks (Hargrove42). Then in the year 1933 he became one of the ...
Tuesday, November 12, 2019
Seed Germination
The time that a seed germinates, and whether or not it actually does germinate, depends on many factors. These factors include; the chemical environment, which must be the right conditions; oxygen must be present, and inhibitory chemicals must not be present. Germination also depends on the physical environment. Temperatures must be suited to the seed, and light quality and quantity must also be suited to the needs of the seed. In some cases, all these conditions are met, and still, the seed fails to germinate. This is because the seed is said to be dormant (Bewley and Black 1985). Seed dormancy is a short-lived deficiency, or block of an able seed to complete germination under suitable conditions. There are two different types of dormancy, embryo, and coat dormancy (Kucera et al.2005). Embryo dormancy is mostly common in woody species, but can also be found in blossoming plants as well. Coat dormancy is when the tissues that enclose the seed are too tight and the seed cannot overcome the constraint. Seeds can be released from dormancy through being chilled, sometimes for several weeks, or sometimes even months, at temperatures of one to five degrees Celsius. This means that seeds that rely on such ways of dormancy must wait for the cold seasons to pass before they can germinate (Bewley and Black 1985). Many seeds can germinate with, or without light, but the plants that require light, are called photoblastic, and are controlled by the phytochrome (Kendrick and Russell 1975). Phytochrome has two descriptions, the first one, Phytochrome red (Pr), is transformed by red light, to the second form, phytochrome far red (Pfr). Far red radiation can reverse the whole process. Phytochrome far red absorbs far red light (730nm), and phytochrome red absorbs red light (660nm) (Toyomasu et al. 1997). Seeds that are grown in darkness donââ¬â¢t germinate unless they are exposed to red light for a short period of time. For a red light to be effective, water content in the seed must be at 15%, because dry seeds do not respond to red light. In lettuce seeds that are matured naturally, phytochrome is most commonly in the form of phytochrome red, and in the dehydrated form, the conversion to phytochrome for red light is not possible (Kendrick and Russell 1975). Lettuce is an important vegetable cultivated worldwide, and requires high quality seeds. Lettuce seeds are unable to germinate in the dark, and are unable to germinate at high temperatures. These characteristics affect the rates that new seeds are developed (Metzger et al. 2009). Light is a very important factor in releasing seeds from dormancy. Seeds can be affected by being exposed to white light from just a few seconds, to or even minutes, others require intermittent light. The light frequency that is required depends on the temperature. Lettuce seeds that are bought in stores are usually treated to improve the germination process, even when lots of light is unavailable. Although, light sensitive leaves need a lot higher levels of phytochrome far red light to bring the seed out of dormancy (Kendrick and Russell 1975). Using all the information I have gathered, I hypothesised that the red light and white light would cause a greater percentage of germination than the other lights, because they produced more far red light. Methods The lettuce seeds that we used (Lactuca sativa L.cv Tango), were dried and stored at 22oC until we used them. We used gibberellin acid (GA3) of âⰠ¥ 90% purity, at the following concentrations; 10-3, 10-4, 10-5, and 10-6. The red light source we used was gathered by filtering white light that came from a twenty-five watt fluorescent bulb, through two layers of dark red cellophane paper. We got the far red light by a forty watt incandescent bulb. The light was then filtered through a container containing 10cm of water, which was placed above the two layers or red and blue cellophane. The white light we obtained was taken from a sixty watt light bulb. Twenty to thirty-five lettuce seeds were placed on two layers of whatman No. 1 filter paper, and all seeds were equally controlled in a room with a green light bulb. In each dish, 5ml of distilled water was added, along with 5ml of its appropriate GA3 solution. The dishes were wrapped in one layer of tin foil, and put in a darkened box. A control was also prepared. The seeds were added to a dish with distilled water. All the experiments were conducted at the same temperature, 24oC. When everything was ready, to figure out how many seeds were germinating, we counted how many seeds in each petri dish had a white radical coming out if it. When we were done, we recorded our results, and pooled them with the rest of the class (Migabo 2011). Seed Germination The time that a seed germinates, and whether or not it actually does germinate, depends on many factors. These factors include; the chemical environment, which must be the right conditions; oxygen must be present, and inhibitory chemicals must not be present. Germination also depends on the physical environment. Temperatures must be suited to the seed, and light quality and quantity must also be suited to the needs of the seed. In some cases, all these conditions are met, and still, the seed fails to germinate. This is because the seed is said to be dormant (Bewley and Black 1985). Seed dormancy is a short-lived deficiency, or block of an able seed to complete germination under suitable conditions. There are two different types of dormancy, embryo, and coat dormancy (Kucera et al.2005). Embryo dormancy is mostly common in woody species, but can also be found in blossoming plants as well. Coat dormancy is when the tissues that enclose the seed are too tight and the seed cannot overcome the constraint. Seeds can be released from dormancy through being chilled, sometimes for several weeks, or sometimes even months, at temperatures of one to five degrees Celsius. This means that seeds that rely on such ways of dormancy must wait for the cold seasons to pass before they can germinate (Bewley and Black 1985). Many seeds can germinate with, or without light, but the plants that require light, are called photoblastic, and are controlled by the phytochrome (Kendrick and Russell 1975). Phytochrome has two descriptions, the first one, Phytochrome red (Pr), is transformed by red light, to the second form, phytochrome far red (Pfr). Far red radiation can reverse the whole process. Phytochrome far red absorbs far red light (730nm), and phytochrome red absorbs red light (660nm) (Toyomasu et al. 1997). Seeds that are grown in darkness donââ¬â¢t germinate unless they are exposed to red light for a short period of time. For a red light to be effective, water content in the seed must be at 15%, because dry seeds do not respond to red light. In lettuce seeds that are matured naturally, phytochrome is most commonly in the form of phytochrome red, and in the dehydrated form, the conversion to phytochrome for red light is not possible (Kendrick and Russell 1975). Lettuce is an important vegetable cultivated worldwide, and requires high quality seeds. Lettuce seeds are unable to germinate in the dark, and are unable to germinate at high temperatures. These characteristics affect the rates that new seeds are developed (Metzger et al. 2009). Light is a very important factor in releasing seeds from dormancy. Seeds can be affected by being exposed to white light from just a few seconds, to or even minutes, others require intermittent light. The light frequency that is required depends on the temperature. Lettuce seeds that are bought in stores are usually treated to improve the germination process, even when lots of light is unavailable. Although, light sensitive leaves need a lot higher levels of phytochrome far red light to bring the seed out of dormancy (Kendrick and Russell 1975). Using all the information I have gathered, I hypothesised that the red light and white light would cause a greater percentage of germination than the other lights, because they produced more far red light. Methods The lettuce seeds that we used (Lactuca sativa L.cv Tango), were dried and stored at 22oC until we used them. We used gibberellin acid (GA3) of âⰠ¥ 90% purity, at the following concentrations; 10-3, 10-4, 10-5, and 10-6. The red light source we used was gathered by filtering white light that came from a twenty-five watt fluorescent bulb, through two layers of dark red cellophane paper. We got the far red light by a forty watt incandescent bulb. The light was then filtered through a container containing 10cm of water, which was placed above the two layers or red and blue cellophane. The white light we obtained was taken from a sixty watt light bulb. Twenty to thirty-five lettuce seeds were placed on two layers of whatman No. 1 filter paper, and all seeds were equally controlled in a room with a green light bulb. In each dish, 5ml of distilled water was added, along with 5ml of its appropriate GA3 solution. The dishes were wrapped in one layer of tin foil, and put in a darkened box. A control was also prepared. The seeds were added to a dish with distilled water. All the experiments were conducted at the same temperature, 24oC. When everything was ready, to figure out how many seeds were germinating, we counted how many seeds in each petri dish had a white radical coming out if it. When we were done, we recorded our results, and pooled them with the rest of the class (Migabo 2011).
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