Wednesday, May 6, 2020
Teenager sexuality refers to sexual feelings, behavior and...
Teenager sexuality refers to sexual feelings, behavior and development in adolescence. It is a stage of human sexuality which is often a vital aspect of teenagersââ¬â¢ lives. Some people believe that sex is essential in every teenage life while other think that it is far better to avoid it till marriage. Studies show that teens are becoming sexually active at younger ages than ever before. This development raises moral, social and health issues as well as considerable controversy. Why this sudden transformation on sexual behavior has happened? What are the major problems and consequences that derive from teenagersââ¬â¢ sexual behavior? Is there a way we could assist to aware this teens about this issue? There are many influences for the increaseâ⬠¦show more contentâ⬠¦However, in some cultures, the media play a role in preventing teenagers to confront scenes related to sex. For example, some intimate scenes are censored in Arab TV channels such as mbc4 and fox movies. ââ¬Å"I believe that sex is a personal choice that one makes and it plays an important role in self discovery and maturity. Sexual experimentation is good experienceâ⬠-Bahij. Curiosity and experience push teens into being intimate with their partners, in that way they believe that they could have a much better understanding when talking about relationship. Sure they been hearing about all the risks or STDs pregnancy... but what is it really like? That is what both boys and girls want to discover and experience. Unfortunately, it is known that few teens have bad intentions since they are pressed to do something that they are not legally allowed to do. Part of it is to feel bad by breaking the law; it is a sort of a rebellion move for them. Teenage sexuality has risen and has become a standard phenomenal in societies. However, there are still some major problems that derive from this issue. These days, the task of teaching moral values has become increasingly difficult in todayââ¬â¢s materialistic, saturated-society. Most parents have the difficult job of preparing their children for conflictShow MoreRelatedThe Sexuality of Adolescent Americans in Juno1555 Words à |à 6 PagesThe Sexuality of Adolescent Americans: Juno Abstract Sexuality and sex in America is a complicated subject in that there is little consensus on the topic of sex in, and the American media sends many mixed messages regarding sex and sexuality to everyone, not just to adolescents. Americans are aware of sex primarily through advertising (print media, commercials, etc.) as sex is used to sell anything and everything. The media also bombards Americans with sexuality and sex on television and inRead MoreApplying Theory1698 Words à |à 7 PagesRunning head: APPLYING THEORY Applying Theory Dinah M. Creamer University of Washington-Tacoma Human Behavior and the Social Environment TSOCW402-Theodora A. Drescher November 24, 2008 OUTLINE This paper will focus on problems commonly linked to adolescents and their formation of relationships by applying attachment theory. INTRODUCTION PART ONE: Development milestones and tasks in adolescents (ages 13 to 18 years) â⬠¢ Attachment experiences â⬠¢ Trust Read MoreSexual Orientation And Identity Of An Individual2117 Words à |à 9 Pagesphysical ability, race and sexual orientation. This dispels out the confusion that exist between sexual orientation and identity of an individual. Sexual orientation is a branch of a personââ¬â¢s identity. Sexual orientation is a branch of personal identity that has existed for long though it is likely to be ignored by many people. From the past, in the peopleââ¬â¢s mindset, it was acceptable, normal and proper for men and women to enter into a sexual relationship. Traditionally, sexual attraction between peopleRead MoreDefinition of Adolescent Development14194 Words à |à 57 PagesDefinition of Adolescent development: The development of children ages 12 through 19 years old is expected to include predictable physical and mental milestones. Introduction Derived from the Latin verb adolescere (to grow into maturity), adolescence is the period of transition from childhood to adulthood. Adolescent is a distinct and dynamic phase of development in the life of an individual. It is a period of transition from childhood to adulthood and is characterized by spurts of physical, mentalRead MoreDefinition of Adolescent Development14200 Words à |à 57 PagesDefinition of Adolescent development: The development of children ages 12 through 19 years old is expected to include predictable physical and mental milestones. Introduction Derived from the Latin verb adolescere (to grow into maturity), adolescence is the period of transition from childhood to adulthood. Adolescent is a distinct and dynamic phase of development in the life of an individual. It is a period of transition from childhood to adulthood and is characterized by spurts of physicalRead MoreWomen s Objectification Of Women3147 Words à |à 13 Pagesactivities. However, along with retrieving a great amount of data from media, teenagers unconsciously adopt attitudes and views, that, to some extent, bias their perception of people around, as well as social roles assumed or believed to be assumed by these people. Thus, as an extensive body of research indicates, girls and women increasingly view themselves, as well as other women, as objects because of constant exposure to sexual objectification across multiple social contexts, including mass media. TheRead MoreImpact of Internet on Children1786 Words à |à 8 Pagesaggressive behaviour Desensitization A. Learning of aggressive behavior ï⠨ According to the social learning theory, children may imitate the acts of aggression as seen through the electronic media (Gunter McAleer 1997:103; Melville-Thomas 1985:9). Children may learn that violence is a useful and appropriate way of solving ones problems. Children can be encouraged to behave more aggressively following exposure to violent behavior. Children who strongly identify with aggressive characters andRead MoreAdolescent Development2890 Words à |à 12 Pagesinfants and children, development will subsequently progress into adolescence, followed by adult, and lastly elderly. The development occur in many fields, namely physical, perceptual, cognitive, moral and social. Adolescence Overview Adolescence is the developmental stage between childhood and adulthood. It generally refers to a period ranging from age 12 and 19. Adolescence has many psychological and social stages, as well as biological. The beginning of adolescence is usually markedRead MoreImpact of Socio-Economic and Cultural Changes on the Personality Development of Adolescents8858 Words à |à 36 PagesIMPACT OF SOCIO-ECONOMIC AND CULTURAL CHANGES ON THE PERSONALITY DEVELOPMENT OF ADOLESCENTS INTRODUCTION 1. The enormous socio-economic and cultural changes coupled with technological revolution have unfolded an urgency to address issues pertaining to grooming up of young personalities beyond the usual concerns of discipline and education in Bangladesh. This is because of the remarkable changes being marked in all the strata of the socio-economic system owing to the first moving cultural transformationRead MoreEffects of Media on Women and Children2408 Words à |à 10 Pagesunrealistic, unhealthy portrayals of female sexuality, sexual health, and shows unnecessary female sexuality and nudity on an immense level. The average woman is misrepresented in the media; this is unhealthy for many women and girls. Studies show viewing sexually objectifying material contributes to eating disorders, low self-esteem, depression and body dissatisfaction. In a 1992 study of female students at Stanford University, 70% of women reported feeling worse about themselves and their bodies
Online Dating Advantages Free Essays
Some advantages and disavantages in online dating. Now days online dating hvae become so commun that everyone know a site or two where can meet or interact with other people becoming making it easy to become part of the online dating trend. But veryb seldon anyone couciously stop to think and anlyze the advantages or disavantages in online dating. We will write a custom essay sample on Online Dating Advantages or any similar topic only for you Order Now In todayââ¬â¢s world everything goes so fast that it seemââ¬â¢s 24 hour days are over for ever, every one is short of time. People running to school, work, appointments, that realistically there is no time to just go out to socialized and interact with friends or just go out. Online Dating, have filled this human need to be loved or wanted by some one else by just flipping tha computer switch or pushing a button. Instantly you have complete access to online world that where you can shoose to be part of to share your momories, fotos,tastes, likes and dislikes to the world. There are two words that plays a key role to the online dating phenomenun; free and instantly. You can freely bacome part of a online community and instatly intereract with those that accept you all for free, bringing this interaction up to your creativity and inmagination to meet as many and different people you would like. Even though, it can be very advantegeous to meet new people online and date,there are deffenetelly some important disavantages to consider. Online dating make it for the most part very easy to interact with so many people at differente place at different time , that you are constantly bonbard with a lot of possibilities. You can date someone today and tomrrow you could date someone else. According to a survey done by fox news, 60 % of online dating participants are actually dating two or more person at the same time. According to the report most people that are engage in online dating, feel that online is just another world , another set of values, nothing like could be judge as real. Moral and values that tend to be pracitce when meeting someone on a local school or live occassion wouldnââ¬â¢t apply to those people met online. For one reason or another, online Dating keep beeing a growing trend, more youngster then ever have access to the internet and actually interacting with others on social sites and dating sites. With advantages and Disavantages today many online users are just so accostome to the online world that they have not even consider any dissavantages since its have just become a way of life. Online dating will continue benefiting those users that engage in an intelligente mature way or disgracing those that have poor judgment. How to cite Online Dating Advantages, Papers
Masks In The Twelfth Night Essay Example For Students
Masks In The Twelfth Night Essay In Ir?ne, Voltaire wrote, ?Shakespeare is a savage with sparks of genius which shine in dreadful darkness of night.? One of Shakespeares sparks of genius was in his use of masks. These masks put characters in a sort of ?darkness of night,? allowing them to become someone else. They are used for imagery, so one can discover who a person is?the inside of the mask. Masks are used throughout Shakespeares Twelfth Night to reveal characters true emotions, to carry the story and explain things to the reader, and to express the power of raw beauty. Shakespeare uses this imagery of a mask in many of his characters in the play, but mostly in two: Viola and Feste. Throughout the play the masks help the plot along. At the end, all masks are discarded for a great finale. The perfect example of the use of masking imagery can be seen in Feste the jester. In the play, Feste shows his many personalities in the disguise of masks. Acting as a wise man contrary to his role of the fool, Feste develops one mask. He tries to ?conceal for what is? (I.ii.52) because he knows that if the people realize his intelligence, he will not be called upon to work. These songs Feste sings serve as symbols of a well-formed conscience. People would stop coming to him for this sound advice he gives. Feste demonstrates a strong example of masking imagery because he shows what the play might be without masks. Later, the ?devil man? (IV.ii. 122) in him surfaces when talking to Malvolio. This is a mask because not only is Feste intelligent, not only is he a fool, he is also conniving. These masks appear all over the play, developing from scene to scene. Feste plays the role of a chameleon; changing masks to become what the necessary character for the given situation. Feste acts as ?an ass? (V.i.16) for his acquaintances. This pleases the people and allows Shakespeare to say outrageous but true things that no other character would say. Although characters wear masks, their true identities are always revealed. Feste says, ?Eyes show days?(II.iii.94). He demonstrates that one can remove a mask just as easily as one can put a mask on. Shakespeare develops all these different masks. Some are used only once or twice; others are used for nearly the duration of the play. Near the opening of the play, when Viola adopts her male identity, she creates another self, like two masks. She may decide to wear one or the other while swinging between the two identities in emotion and in character. She decides to take on this identity because she has more freedom in society in her Cesario mask, which is evident when Orsino accepts her, whereas, in her female identity she would not be. The mask of Cesario develops throughout the play. Violas mask pulls the comedy together. First, Violas mask serves her in getting a job to get back on her feet after nearly drowning. This mask helps other people too. The mask gets Olivia back on her feet. She escapes the mourning of her dead brother. Olivia realizes she has something to live for after seeing Cesarios mask. Falling in love with the male version of Viola works out well. The mask turns out to be a replica of something that does exist. Sebastian is there, married to Olivia, when all masks are removed. The mask, growing on Viola, shows importance all over the play. It continues to develop, and this leaves the reader an even more omniscient point of view. While Olivia, Sir Toby, and Sir Andrew are clueless as to what is going on, we know about the masks. Shakespeare wanted his readers to stand by and laugh. .u1b47f78125a8780cc46ab15a497aff37 , .u1b47f78125a8780cc46ab15a497aff37 .postImageUrl , .u1b47f78125a8780cc46ab15a497aff37 .centered-text-area { min-height: 80px; position: relative; } .u1b47f78125a8780cc46ab15a497aff37 , .u1b47f78125a8780cc46ab15a497aff37:hover , .u1b47f78125a8780cc46ab15a497aff37:visited , .u1b47f78125a8780cc46ab15a497aff37:active { border:0!important; } .u1b47f78125a8780cc46ab15a497aff37 .clearfix:after { content: ""; display: table; clear: both; } .u1b47f78125a8780cc46ab15a497aff37 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u1b47f78125a8780cc46ab15a497aff37:active , .u1b47f78125a8780cc46ab15a497aff37:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u1b47f78125a8780cc46ab15a497aff37 .centered-text-area { width: 100%; position: relative ; } .u1b47f78125a8780cc46ab15a497aff37 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u1b47f78125a8780cc46ab15a497aff37 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u1b47f78125a8780cc46ab15a497aff37 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u1b47f78125a8780cc46ab15a497aff37:hover .ctaButton { background-color: #34495E!important; } .u1b47f78125a8780cc46ab15a497aff37 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u1b47f78125a8780cc46ab15a497aff37 .u1b47f78125a8780cc46ab15a497aff37-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u1b47f78125a8780cc46ab15a497aff37:after { content: ""; display: block; clear: both; } READ: voting Essay Viola plays the right person at every point in the story to make a happy ending. She removes her mask at the perfect moment. Being both a ?maid? (V.i. 267) and a ?gentleman? (V.i.269) makes this plot what it is. She carries out the functions of both genders, and she is judged from both. The masks deceive. Thinking that Viola is a man, even her brother Sebastian is confused about Violas true identity. She makes her brother think he doesnt ?know by voice or any other feature.?(III. IV.325) This shows that she can fool even the closest of kin thorough the mask. At the end of the play, when all tricks and treacheries are revealed and all masks are lifted, Orsino falls in love with Viola. He first forgives her of her duty to him then says that she shall be her masters mistress as soon as she completely reverts to her female form. The imagery of masks in this play proves to be very well developed in both Feste and Viola. Developing the imagery created by the mask helps to make the whole play more understandable to the reader. Each mask is well developed and has a definite meaning to the reader. Masks are used to conform to ones own needs or to the needs of others, just as in real life. In the book, masks are used to hide something. Everyone eventually came out from that hiding. With masks removed, quality of life improved in the end and everyone became happy. Masks added a lot to Twelfth Night, but Shakespeare was trying to show his readers how much better the world could be if people took off masks. Shakespeare Essays
Monday, May 4, 2020
How to Forget Someone You Love free essay sample
How do we forget someone that has been a part of our lives for a quite some time? We find it hard at times when we actually want to forget them but still cant because theyve been something to us. Some get depressed, and some get stressed out with the things around them some get drunk and put their selves to trouble Just to forget the hurt that they feel. But where do they end up? Some In the Jail for their stupidity, some are stuck In the past and dont know how to get out and move out of the box that they are in, and some still cant stand up tall and sayVive finally moved Well, here are some effective tips for you Step one: Set aside all the things that can make you remember this person! How do you do It? In a big box, you put everything there. We will write a custom essay sample on How to Forget Someone You Love or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Pictures, stuff toys, or whatever this person gave you. After, you can put them away and put In the balcony or somewhere you wont be able to see it for a long period of time. Just be sure you will not go to that place and check everything out. Also, start removing and forgetting all the contact numbers you have connecting to this person.If possible, delete them in your personal accounts too like Backbone, Yahoo! Messenger, MS Live, Keep and all other social sites where you can see his or her updates. Step two: Be strongly Show this person that you can do it without them! Get all the confidence you could before you meet him the second time around after they leave you. Show him/her that its their lost, not yours! Theres going to be a big difference with the way they will treat you. Step three: Get busy! Focus yourself on other things like studies, friends, family and other happy things. Go on a arty with your awesome buddiesHAVE FUN! Drink if its going to ease the pain but remember not to get wasted. Its going to bring back all the pain and let you drag yourself down! Step four: Life must go on! Not Just because this someone special left you, you lose hope with everything. Remember: The most revengeful thing that you can do to the person who left you is to be happy. Put a big smile on your face and tell the world you can do it! Step five: Think of happy thoughts! Never let yourself down with the memories that will melt your heart and cry. Think of the stuffs that cake you happy even if youre all alone.Have yourself a treat at the mall or go on a shopping that will make you happy. Do the things that will make you happy even without accompany of others. NEVER watch romantic movies! Youll Just hurt yourself twice as much as you can remember. Step six: Stand up tall with chin up! Prove the people around you that you survived everything youve been through. When you see this person, walk in front of them with all the confidence you have! If theyll notice you, say Hal or hell for them not to feel that you were very affected with what they id to hurt you. After all that was said here, its still you whos going to decide on what to do. This might help, but everything is still up to you. Its going to be easy and yet, difficult. Just like math, X and Y are there but you still have to calculate it properly to get the answers correctly. Everything worth having is worth waiting. How to Forget Someone You Love By ohyiieeee because theyve been something to us. Some get depressed, and some get stressed to forget the hurt that they feel. But where do they end up?Some in the Jail for their tepidity, some are stuck in the past and dont know how to get out and move out of things that can make you remember this person! How do you do it? In a big box, you can put them away and put in the balcony or somewhere you wont be able to see his or her updates. Step two: Be strong! Show this person that you can do it to be a big difference with the way they will treat you. Step three: Get busy! Focus see this person, walk in front of them with all the confidence you have!
Tuesday, April 14, 2020
Sample Photo Essay Pitch
Sample Photo Essay PitchA sample photo essay is probably the most important element of a successful essay. It can make or break your chances of getting accepted for your thesis. Of course, you must have good essay skills to get your essay accepted. But the most important aspect of your essay is your ability to put your thoughts and ideas in a sentence that is brief and clear.There are several ways in which a writer can capture the reader's attention with their essay. But in order to get people to actually read your essay, your focus should be on making your essay stand out among other similar works that have been submitted.An article in a magazine is a great place to begin. Articles are usually short and provide a basic outline of your topic. Make sure your article is written in a professional and simple tone, but make sure you are capable of putting some emotion into your work.Another great source of material that will help your reader to identify with your essay is a television com mercial. These ads are easy to understand and they are usually about solving a common problem faced by millions of people each day.Use this as a springboard to write about something you know and something that is very personal to you. You can also choose to create a dramatic piece of writing by using images from your own life.The next best thing to use as a sample to write a photographic essay is a travel brochure. These types of brochures often feature images of fascinating locations and cities around the world. Use these as a basis for your work, but also make sure that the images are properly processed.However, one of the best things to use as a basis for your photo essay is still a personal article about something that you know well. Start by writing a simple article that you can then turn into a photograph.All of these forms of writing are examples of sample essays, and each one can form the basis of a complete thesis. The key to writing a successful photo essay is making sure you fully understand the concept that you are trying to express. You can do this by using different tools in order to get a feel for how to write your thesis.
Sunday, March 29, 2020
Baby Boomer and Health Care free essay sample
The change with the aging population has never been so high as before. As the demographics of the aging populations continues to grow society will be seing thesome growing pains. The cause for the aging population is due to the amount of baby boomer in this generation . The term baby boomers are people who were born from 1947 to 1964. These people were born doing the post-world war II baby boom. The impact of the baby boomers will be mostly felt in healthcare. With the aging population most of the population most of them will depend on medicare to cover health concerns , which will imact everyone in the united state. The demographic of the aging pouplation will also create a demand for more health care professionals. They will more needs for geriatric experts including physical therapy, and mental helahtcare workers. Those are profession who will end up neededing workers in the near future and it will only expand even more. We will write a custom essay sample on Baby Boomer and Health Care or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page The pupose of this paper is to dicuss the demographic impact of the aging population in Chicago illinios. The paper will dicuss The numbers related to the demographic population in Chicago Illinois. The impact of this demographic group on health care costs and services in Chicagds ommunity/region. The paper will discuss the major issues this population faces such as how will they pay for long-term care? What transportation is available and what other types of facilities are in their area?. and finally the paper will cover What is being done to ease the impact of the identified issue and future recommendations. demographic impact of the aging population in Chicago Illinios In the Chicago community balancing the budget is already difficult do to the current recession in over the next decades the cahlleges will get even worst the budget will become even larger. The first round of babboomers was eligible for retirement benefits social security in 2008 and will be eligible for medicare beginning of 2011. Managaging the budget efficiently should be a very important goal for law makers because later on most of the nation will be threaten. With the baby boomers becoming eligible for service such as social security, medicare and other government assistance . because of the aging population services will be cut for those who are not eligible for retirmane or medicare . government services will decrease because the federal government will face more challenges and a much higher budget. Cutting services in some regions in Illinois is going to increase the poverty rate. Regions such as the south side of Chicago over 50 percent of the population are relying on government assistance such as Medicaid,cash assistance, housing/shelters, WIC and Food assistance. With the aging population some of these services will be cut and the to be eligible for some of these service will become much more difficult. The impact of this demographic group on health care The healthcare field is definitely going to feel the the impact of the aging population. The number of healthcare professionals will decrease as they age and most of them find it challenging as some of their most reliable and knowledgeable employees are retiring. The aging of the population will greatly affect some of the skills and services the health care workforce must be equipped to provide, and the settings in which this care is provided. Theres already a shortage for healthcare professionals such as, Physicians, Nurses and other healthcare providers. The aging population is one of the cause for such shortages. With that beind said quality of care will worsen ecause not that many people is attending nursing school or medical school with the babyboomers retiring the healthcare workers who are left are going to be handling a work load of three nurses instead of one. One of the question often ask is who will take care of the aging population and who will pay for it. Older adults has more chances of getting ill, with health disease,and other chronic deseases. The aging population place more pressure on the Medicaid, medicare and pivate insures to contro healthcare cost. The federal government is know where near ready when it ome to fguring out the best way to care for the aging population. The aging population will aso reslt risng average paetin acuity, this will rewuire a higher nurse and physician staffing levels . it has beend said the future elderly may lower the disability rates than todays elderly controlling for age, that because it has been much of improvements in economic resources, medical technology education levels, public helath, lifestyle, and medical technology. The numbers related to demographic population in chicagos/region As the aging population know as the baby biimers move to retirement most of the opulation will skyrocket nationally not only in chiago Illinois the aging population was 12. 4 percent in 2000 by the year 2030 it will rise to 19. 7 percent that huge increase. In Illinois the aging puplation was 12. 1 percent in 2000; it is projected by 2030 it will become 18 percent. By the year 2050 seniors ages 85 and up will triple by the year 2050 nationwide which will cause nursing home impact.. The number of persons 60 years of age and older in the state of Illinois is expected to increase from 2 million today to over 3. 6 million by the year 2030. With the agingpopulation most of hem will end up having to receive long term care. Medicaid nursing home patients will continue to grow and the people paying for these baby boomers long-term care are working citixens. With that being said long-term care liabilities will increase even more. More seniors will start incorporating into community care program, and the cost to stay in the nursing home will increase. Metlife stated in 2006 to 20070n average a 3 percent increase in nursing homw cost by the year 2020 this number will triple. the aging population will not only impact citizens it will also impact state Medicaid, prescription drug, and aging programs. The aging population will cause high cost and higher demand of longterm/Medicaid, it will increase programs the Chicago region has for the elderly and loss of revenue because of senior tax breaks. The major issues the aging population faces One of the issues the aging population faces is not having enough resourseces or medical staff for care. With so many elderly on demand for care medical staff are going to be over worked which can lead to medical erros occurring. The weigh time enough supply to go around. Transportion will also be a major issue the aging opulation twill face specialy in the south side of Chicago half of the aging individuals are already without a vehicles. The Illinois department of aging report the major issues the aging population will face in Illinois is shortage of affordable housing, accessible housing, Longer wiat time for transportation pick up. They will face lack of Reliable and safe transportation. Most of the hospitals are far away from the south side of Chicago because of the high crime and violence i. b with hospital being so far away elderly will suffer and it may be to late by the time they make it to the hospital.
Saturday, March 7, 2020
Introduction to Monomers and Polymers in Chemistry
Introduction to Monomers and Polymers in Chemistry A monomer is a type of molecule that has the ability to chemically bond with other molecules in a long chain; a polymer is a chain of an unspecified number of monomers. Essentially, monomers are the building blocks of polymers, which are more complex type of molecules. Monomers- repeating molecular units- are connected into polymers by covalent bonds. Monomers The word monomer comes from mono- (one) and -mer (part). Monomers are small molecules which may be joined together in a repeating fashion to form more complex molecules called polymers. Monomers form polymers by forming chemical bonds or binding supramolecularly through a process called polymerization. Sometimes polymers are made from bound groups of monomer subunits (up to a few dozen monomers) called oligomers. To qualify as an oligomer, the properties of the molecule need to change significantly if one or a few subunits are added or removed. Examples of oligomers include collagen and liquid paraffin. A related term is monomeric protein, which is a protein that bonds to make a multiprotein complex. Monomers are not just building blocks of polymers, but are important molecules in their own right, which do not necessarily form polymers unless the conditions are right. Examples of Monomers Examples of monomers include vinyl chloride (which polymerizes into polyvinyl chloride or PVC), glucose (which polymerizes into starch, cellulose, laminarin, and glucans), and amino acids (which polymerize into peptides, polypeptides, and proteins). Glucose is the most abundant natural monomer, which polymerizes by forming glycosidic bonds. Polymers The word polymer comes from poly- (many) and -mer (part). A polymer may be a natural or synthetic macromolecule comprised of repeating units of a smaller molecule (monomers). While many people use the term polymer and plastic interchangeably, polymers are a much larger class of molecules which includes plastics, plus many other materials, such as cellulose, amber, and natural rubber. Lower molecular weight compounds may be distinguished by the number of monomeric subunits they contain. The terms dimer, trimer, tetramer, pentamer, hexamer, heptamer, octamer, nonamer, decamer, dodecamer, eicosamer reflects molecules containing 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and 20 monomer units. Examples of Polymers Examples of polymers include plastics such as polyethylene, silicones such as silly putty, biopolymers such as cellulose and DNA, natural polymers such as rubber and shellac, and many other important macromolecules. Groups of Monomers and Polymers The classes of biological molecules may be grouped into the types of polymers they form and the monomers that act as subunits: Lipids - polymers called diglycerides, triglycerides; monomers are glycerol and fatty acidsProteins - polymers are known as polypeptides; monomers are amino acidsNucleic Acids - polymers are DNA and RNA; monomers are nucleotides, which are in turn consist of a nitrogenous base, pentose sugar, and phosphate groupCarbohydrates - polymers are polysaccharides and disaccharides*; monomers are monosaccharides (simple sugars) *Technically, diglycerides, and triglycerides are not true polymers because they form via dehydration synthesis of smaller molecules, not from the end-to-end linkage of monomers that characterizes true polymerization. How Polymers Form Polymerization is the process of covalently bonding the smaller monomers into the polymer. During polymerization, chemical groups are lost from the monomers so that they may join together. In the case of biopolymers of carbohydrates, this is a dehydration reaction in which water is formed. Resources and Further Reading Cowie, J.M.G. and Valeria Arrighi. Polymers: Chemistry and Physics of Modern Materials, 3rd ed. Boca Taton: CRC Press, 2007.Ã Sperling, Leslie H. Introduction to Physical Polymer Science, 4th ed. Hoboken, NJ: John Wiley Sons, 2006.Ã Ã Young, Robert J., and Peter A. Lovell. Introduction to Polymers, 3rd ed. Boca Raton, LA: CRC Press, Taylor Francis Group, 2011.
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