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MBA 525 Saint Leo University Top Three Skills to Improve Email Communication PPT

MBA 525 Saint Leo University Top Three Skills to Improve Email Communication PPT.

You will prepare a “Top 3” presentation on a topic of your choice that
has been covered in modules one through four. The format can be the “Top Three
Reasons…” or “The Top Three Skills For…” for example. Pick either Top three Reasons…. or The Top Three Skills…. I have upload everything you need including the chapter I want you to use for the presentation. You can only use scholarly references. APA format and cite all in text references also if you use something from the writer. Not too wordy on the slides, use pictures to reference what you have written on the slides, and add some notes on the bottom of the slide(speaking points for when I present) I will also upload the basic format for the slides from my professor and the grading rubric. Professional layout for the slides, use the same font throughout the slides. The book has to be one of your references. Again, everything is upload for you and besides the chapter, maybe you can add two more scholarly references
MBA 525 Saint Leo University Top Three Skills to Improve Email Communication PPT

CSR- History and Introduction Over the years, there has been contention among scholars and industry experts on what exactly CSR means. Unfortunately, the contention and the debate that ensues have not resulted in a standard definition yet. Consequently, different people have different definitions of the term, and some scholars have even accused some researchers of distorting the CSR concept, so much that, it has become “morally vacuous, conceptually meaningless, and utterly unrecognizable” (Orlitzky 48). Although scholars argue that CSR dates back to the 1920s, its first conceptualization in literature began in 1953, when Howard Bowen, an American Economist stated that organizations had a social obligation “to pursue those policies, to make those decisions, or to follow those lines of action which are desirable in terms of the objectives and values or our society” (Bowen cited by Maignan and Ferrell 4). Following the conceptualization of CSR by Bowen in the 1950s, other CSR-related concepts such as corporate citizenship, social audits and corporate stewardship came into focus (Maignan and Ferrell 4). From the 1960s onwards, scholars and researchers have been more concerned about defining the CSR concept. Defining Sustainability and CSR The 1987 Brundlandt report closely ties sustainability to the sustainable yields concept. Specifically, the report argues that “sustainable yields development meets the needs of the present without compromising the ability of future generations to meet their own needs”. In other words, the Brundlandt report argues that sustainability is possible if the organizations (and humankind in general) consider the social, economical and ecological aspects similarly. According to the report, organizations need to be responsible for their actions and inaction in both the short-term and long-term; if at all sustainability is to be attained. The report posits that the present action or inaction by organizations have an impact not only on its stakeholders, but also on the larger humankind with the inclusion of future generations. Even though there is no standard definition of CSR, a literature review conducted by Dahlsrud reveals that a definition by the Commission of the European Communities is the most prevalent in literature. The Commission defines CSR as “a concept whereby companies integrate social and environmental concerns in their business operations and in their interaction with their stakeholders on a voluntary basis” (Dahlsrud 7). Among other terms that are popular in CSR definition include adhering to ethical values, complying with legal requirements, respecting communities, the environment and people, and contributing to the quality of life of the stakeholders and the larger communities. Among the vital indicators that come out of the CSR literature is the fact that organizations should not just pursue profitability without paying attention to the effect that their activities have on the employees, shareholders, communities, and the environment. Get your 100% original paper on any topic done in as little as 3 hours Learn More The importance of CSR for Textile and Apparel Industry The textile and apparel industry has an infamous reputation for its use of cheap labor often sourced from overworked employees or underage workers. Most notable is the fact that most such industries are now in developing countries where labor laws are virtually non-existent, while unemployment rates are remarkably high. Such combination of factors means that organizations can maximize output by overworking employees who are desperate to eke out a living in whatever way, and compensating them with relatively low wages. The lack of legal and political frameworks in developing countries means that major players in the textile and apparel industry need to take the CSR initiatives a notch higher in order to cover for the management gap created by such legal and political inadequacies. After all, (Maignan and Ferrell 4) indicate that CSR operates outside the legal entitlement of an organization, and is usually voluntary in nature. Why is CSR needed? The need for CSR in the textile and apparel industry is underscored by the fact that in view of the lacking political, social and legal guidelines, the organizations operating in the industry have societal obligations that they need to meet. Notably, the need for such organizations to deliver societal values amidst high levels of poverty and insecurity where their business interests are located cannot be overemphasized. Besides, the CSR hype has alerted employees, government, consumers and larger societies of the social responsibilities that organizations have towards them. Hence, adopting CSR initiatives serves the strategic business interests of organizations operating in the apparel and textile industry since it enables organizations to forge good and beneficial relationships with not only the employees, but also governments, non-government organizations and consumers. The nature of fashion industry The nature of the fashion industry is such that there are high lead times that require organizations to produce fashionable clothes at relatively low costs. The CSR in the fashion industry is therefore more focused on the production processes whose end results are the clothes people dress in. To this end, (Dickson and Eckman 188) argues that CSR in the fashion industry is “an orientation encompassing the environment, its people, the apparel/textile products… and the systematic impact that production, marketing and consumption…has on multiple stakeholders and the environment”. Among the key factors that influence CSR in the fashion industry include the production of raw materials at the farm level, the production processes at the firm level, and the operational factors such as sweatshop and child labor. We will write a custom Term Paper on Corporate Social Responsibility and Apparel Industry specifically for you! Get your first paper with 15% OFF Learn More On the environmental front, the extensive exploitation of natural resources such as water and farm land, and the use of chemical products impact negatively on the environment. Companies that have embraced CSR in the fashion industry therefore seek to address such issues though responsible and sustainable initiatives. The background: conditions that propel companies to take sustainability into consideration In literature, there are two basic reasons that propel companies to take sustainability into consideration: (I) the need to look good in the eyes of the employees, the consumers and other stakeholders; and (II) A genuine need to do well, and contribute to the welfare of all stakeholders affected by what the organization does. In the first instance, organizations find adopting CSR initiatives necessary due to the reputational risk that comes with non-adoption. In the Nike case (explained elsewhere) for example, the firm was criticized for the use of child labor in its value chain, and the effect of such criticism in its sales volume in 2004 was far-reaching. Internally, companies with a good social responsibility reputation are able to attract and retain employees more, while investors are willing to invest in such firms. In the second instance however, organizations adopt CSR/sustainability simply because “it is the right thing to do”. The evolution of company’s initiatives- from merely safe guarding image to integrating it as part of their business strategy CSR is no longer part of public relations practices for organizations. Rather, CSR is now being incorporated as part of the business strategy that organizations take. In the past, firms focused more in corporate communications and corporate philanthropy; nowadays however, CSR is viewed as an important differentiation tool especially in the competitive markets. As Gildea notes, the consumers is at the middle of the revolution since contemporary purchasers boycott goods or services whose production harms the people, the society or the environmental resources (Gildea 21). Public pressure Non-governmental organizations (NGOs) have been on the fore front mobilizing and applying pressure on companies that violate what is considered as socially responsible/sustainable production or manufacturing processes. Among the most effective public pressure means are consumer boycotts. A 1990 article in the Economist, for example stated that “pressure groups are besieging American companies, politicizing business and often presenting executives with impossible choices. Consumer boycotts are becoming an epidemic for one simple reason: they work” (The Economist 69). The public pressure through boycott is usually marked by negative publicity focusing on what a firm did or failed to do, and such sentiments usually affect its sales volumes and profitability. The public pressure is intended to coerce targeted companies to change their policies regarding an issue; or to communicate displeasure regarding how the target firm is handling an issue. Not sure if you can write a paper on Corporate Social Responsibility and Apparel Industry by yourself? We can help you for only $16.05 $11/page Learn More Global Sourcing Shift The global sourcing shift is a product of globalization, where branded apparel manufacturers, lead firms, marketers and retailers in developed countries have all turned to bulk importation of their products from global suppliers, usually in developing countries (Gereffi 1). Social and economic impact on countries It has been argued that the relocation of apparel manufacturing industries to countries with cheap labor tantamount to moving jobs that would otherwise benefit local populations abroad. Incidentally, firms that have relocated their production to cheaper destinations usually have their largest markets in the same destinations they re-located from. On the counter side however, developing countries where such factories are located benefit from foreign direct investments that creates jobs and earns such countries foreign exchange revenue from exports. However, such countries are now being forced to play catch-up with the developed countries as far as labor and environment-related laws are concerned. Walmart The catalyst of the Walmart’s Sustainability strategy A report by the Stanford Graduate School of Business indicates that the Sustainable Value Networks (SVNs) adopted by Walmart acts as catalysts to the chain store’s sustainability strategy. Through the SVNs, Walmart is able to focus on specific areas in its supply chain such as food packaging, transportation or buildings among others. The chain store identifies and develops any change that may improve sustainability in focus areas. Through the SNVs, Walmart identifies areas where it can enhance efficiency and/or reduce waste either single handedly or through engagement with its suppliers and other stakeholders. The details of the strategy – specifically to textile and apparel In the textile and apparel industry, the SNVs strategy in Walmart entails extensive life-cycle analyses done on the apparel production processes with the intention of understanding the exact impact that such processes have on the environment. According to the report by the Stanford Graduate School of Business (6), it was found that “soap was responsible for an alarming level of greenhouse gas emissions, primarily due to the palm oil used in soap products”. Consequently, Walmart started working with suppliers in view of introducing the sustainable use of palm oil in soap products. Walmart and Patagonia In 2010, news broke that Walmart and Patagonia were partnering in order to help the former “move up the sustainable business learning curve fast” (Kimball n.pg.). Through the partnership, Patagonia would help Walmart in developing a sustainability index for its products like it (Patagonia) had done with other entities such as Nike and North Face. As Walmart sought to introduce a scorecard to rate all its products on social impact and eco-friendliness, Patagonia seemed like the most ideal partner (Kimball). It is worth noting that Patagonia is revered as a leader in sustainable business practices. Progress- result In just one year, the Walmart-Pantagonia partnership has opened up to include other players in the apparel industry leading to the formation of the Sustainable Apparel Coalition (SAC). SAC has 40 members, who include industry heavy weights such as Patagonia, Walmart, Nike, Gap, and JC Penney among others. Together, the 40 member in SAC came up with the Sustainable Apparel Index, which is defined as an “Industry-wide tool for measuring the environmental and social performance of apparel products and the supply chains that produces them” (Kirsten n.pg.). Through the index, the SAC members hope to promote efficient use of water and energy; less use of chemicals; less waste production; and enhance the working conditions in the apparel industry (Kirsten). Nike The initiatives that Nike have undertaken Ever since the 1990s when Nokia took a hit from consumer boycotts and other forms of public pressure for the alleged use of child labor and sweatshop conditions by some of its suppliers in Asia, the company has taken up CSR initiatives to remedy its dented image. Key among such initiatives was the introduction of a Code of Conduct, which the company demanded that all its suppliers should abide to (Locke, Qin and Brause 8). The company has further put the minimum age for workers to 18 years, and insists that the indoor air quality in all its supplier factories must meet the ‘Occupational Safety and Health Administration’ (OSHA) standards as used in the US. To boost compliance, (Locke et al. 9) observe that the company trains its suppliers, and has put together a team that monitors compliance in 21 countries. By 2008, Nike has a further 1,000 production specialists employed to work with its suppliers globally for purposes of enhancing compliance to the Code of Conduct. But perhaps the most significant CSR initiatives by Nike are in the auditing systems, which include: (I) ‘Environment, Safety and Health (SHAPE) audit’; (II) ‘Management and Working Conditions Audit (M-Audit)’; and (III) annual inspections by the ‘Fair Labor Association (FLA)’ (Locke et al. 9). The minimal impact in monitoring While monitoring is one way of ensuring compliance of CSR and sustainability initiatives along the supply chain, its impact is often cited as inadequate (May, Cheney and Roper 413). In the apparel industry for example, questions are raised about whether CSR should just stop at ensuring that underage labor is not used, or whether organizations should go a step further and ensure that children go back to school. Enforcing/ Monitoring CSR initiatives Enforcing and monitoring of CSR and sustainability initiatives have been the subject of countless debates, both at the organizational level and on other social levels (May et al. 413). The European Union for example founded the ‘Business Social Compliance Initiative (BSCI)’ for purpose of monitoring how organizations complied with established social standards. The monitoring is either scheduled or impromptu. While the enforcement of CSR initiatives especially in the Apparel industry is left to individual companies, monitoring is conducted by accredited monitors or independent monitoring agencies. Lack of effectiveness The lack of effectiveness in enforcement and monitoring of CSR initiatives is persistent in the apparel industry. Companies which shadow dress their production processes in order to create a positive feedback usually improve the working conditions whenever a scheduled audit is about to happen. To increase effectiveness in enforcement and monitoring of CSR initiatives it is recommended that auditors should make impromptu visit to companies, establish complaint procedures for employees and other stakeholders, establish contact with local government agencies, and check and audit the company records regularly. Conclusion Summary Generally, CSR initiatives lead to better working conditions for employees, cleaner production processes, energy efficiency and enhanced employee and consumer loyalty. Hence, organizations not only reap direct and indirect benefits from the CSR initiatives. Suppliers in the apparel industry are for example able to attract big clients and even financiers who are keen to protect their brand reputations. In the end, CSR becomes a business strategy, which effectively increases the gross returns in firms in the apparel industry. Challenges still faced One of the major challenges in CSR is contained in the fact that the concept is more of a fad than the reality in most contemporary firms. Hence, firms attempt to ‘look good’ by claiming to adopt CSR/sustainability initiatives, while the reality may be completely different. Additionally, the imprecise definition of the CSR concept may mean that different firms adopt different CSR initiatives, which as (May et al. 413) observe, may not be sufficient enough to address the contradictions caused by capitalism on societies. In the apparel industry for example, CSR may not be able to compensate indigenous people who have been of the receiving end of poor working environments, poor pay, long working hours and victimization at the work place. Recommendations Awareness creation regarding CSR practices and issues is needed if at all companies regardless of their sizes or financial positions are to benefit from the concept. Additionally, solutions to the different challenges facing the textile and apparel industry need to be found. For example, the competing codes of conducts need to be rationalized. Lastly, (May et al. 413) observe that implementation and evaluation of CSR initiatives is always done away from the public eye, and this may create room for organizations to whitewash their activities by initiating programs, which are never followed up, or implemented to the full. In future, the implementation and evaluation of such initiatives should be conducted in a transparent manner. Works Cited Dahlsrud, Alexander. “How Corporate Social responsibility is defined: an Analysis of 37 Definitions.” Corporate Social Responsibility and Environmental Management, 15 (2008): 1-13. Print. Dickson, Marsha and Eckman Molly. “Social Responsibility: The Concept as Defined by Apparel and Textile Scholars.” Clothing and Textiles Research Journal, 24 (2006): 178-191. Print. Gereffi, Gary. “Global Sourcing in the U.S. Apparel Industry.” Journal of Textile and Apparel, technology and Management, 2.1 (2001):1-5. Print. Gildea, Robert L. “Consumer Survey Confirms Corporate Social Action Affects Buying Decisions.” Public Relations Quarterly, 39 (1994-95): 20-22. Print. Kimball, Jay. “Walmart Partnering with Patagonia on Sustainable Business Practices.” 8020 Vision, 01 Jul. 2010. Web. Kirsten, Ann. “Promoting Sustainable Apparel.” Katerva, 2 Aug. 2011. Web. Locke, Richard, Qin Fei and Brause, Alberto. “Does Monitoring Improve Labor Standards? Lessons from Nike.” Industrial and Labor relations Review, 61.1(2007): 3-31. Print. Maignan, Isabell and Ferrell O.C. (2004). “Corporate Social Responsibility and Marketing: An Integrative Framework.” Journal of the Academy of Marketing Science, 32.1(2004): 3-19. Print. May, Steve Kent, Cheney George and Roper Juliet. The Debate over Corporate Social Responsibility. Oxford: Oxford University Press, 2007. Print. Orlitzky, Mark. “Payoffs to Social and Environmental Performance.” Journal of Investing, 14.3 (2005):48-51. Print. Stanford Graduate School of Business. “Walmart’s Sustainability Strategy (B): 2010 Update.” (2010):1-21. Print. The Economist. “Boycotting Corporate America.” The Economist, 26 May (1990): 69-70. Print.
Introduction There are several theories developed by philosophers to understand personality. According to Cervone (2001), dispositional theories can be described as a combination of numerous thoughts regarding the personality of human beings. These theories try to relate the character traits of an individual to personality. The most popular dispositional theories are; the individual psychology theory and the trait and factor theory. Individual psychology theory, developed by Gordon Allport, is rooted on the fact that human beings exist in uniqueness, diversity and permanence of personal growth. On the other hand, trait and factor theory give emphasis to the application of factor analysis, a mathematical procedure used in reducing many variables to a small number. This is useful since many traits of an individual can be cut down to particular traits that are used in describing an individual’s personality. One of the major drawbacks of Allport’s theory is that it is not grounded on scientific research. As such it can never be proved and does not explain the unconscious behaviors. Conversely, trait and factor theory embraces lots of research and believed to be accurate. However, it is more suitable to researchers than parents, educators, and counselors. Description of how dispositional theories affect individual personalities Dispositional theories help in understanding the diverse personality elements amongst individuals. The way an individual respond to different situations is based on his or her attitudes, feelings, perceptions, interests and other sensations. Dispositional theories explain how these behaviors are portrayed in different individuals. Primarily, the individual personality theory undertakes that different individuals have varied kinds of behaviors. Despite the fact that a group of persons may seem to have the same characters, each person portrays certain distinctive attributes. For example, different individuals have different views regarding life. While some people may have optimistic perceptions about life others may be cynical. Gordon Allport assumes that dispositional features of an individual appear as traits and causes of personality. According to the theory, some character traits of an individual are cardinal, which means that they can be observed by everybody and are not concealed. Nonetheless, some behaviors are more elusive and may be observed in some situations only, like when an individual is stressed (Feist

Immunity and the Lymphatic System, biology homework help

Immunity and the Lymphatic System, biology homework help.

Oh…My Crazy Stress Hormones!
Annie is a new district attorney (DA) for her county and she has her first day in court. She walks into the courtroom and sits at the plaintiff’s table. She feels pretty relaxed and is excited about her first case as a DA; but she is also nervous. The judge enters the courtroom, introduces the case and asks Annie to make her opening statement. As Annie begins to stand, she suddenly feels terror, her hands are trembling, her heart is racing, her mouth is dry and she thinks that she may faint. What is Annie experiencing? What are the three stages of General Adaptation Syndrome (GAS)? What stage is she currently experiencing? What hormone is released during this phase and how does it affect the body? What are the main organs involved in this response? What techniques do you recommend to help Annie calm down? Think about your own experiences. Describe an incident where your system activated the “fight or flight response.’ What caused this reaction? How did you feel? What was the outcome? Be sure to explain in your example how many of the GAS stages you experienced. What is post-traumatic stress disorder (PTSD)? What stage of GAS is affected in PTSD? What treatments are available for PTSD?
Immunity and the Lymphatic System, biology homework help

Critique of The Article Winged Barometers Impacted by A Changing Climate Essay

essay writer Critique of The Article Winged Barometers Impacted by A Changing Climate Essay.

Attached Files: Final Paper- MLA Birds.pdf (86.95 KB) Please read the student research paper called “Winged Barometers: How birds are impacted by a changing climate” and write a 250 word (1 full page) response to this paper. In this response, your job is not to debate this student. Your job is to first look at what this student does well in this paper, and discuss some of the SUCCESSFUL writing strategies, rhetorical techniques, and the types of evidence the author uses. You may select from this list, or you may find other strengths in this paper to discuss. If you do select from this list, provide examples of where the author accomplishes these positives. Then, looking at the same list, which of these areas could the author have improved upon to make this paper more persuasive?engaging introduction with clearly stated thesispersuasive stanceengaging conclusion with important final thoughtcredible sources, with source backgrounds providedcurrent sources that show recent researcha mix of emotion, logic, and ethicsconsideration of other viewpoints or perspectives on the issuewell written, careful editing and proofreading, MLA formatevidence plus analysis of evidencedirect quotes to support important pointsquotes are not too long – good combination of summary, quotation, and paraphrasegood combination of types of research sourcesprimary and secondary researchin text citations so reader knows where research comes fromworks cited page CORRECTLY organized
Critique of The Article Winged Barometers Impacted by A Changing Climate Essay

Computer Science homework help

Computer Science homework help. This following essay entails doing an Analysis on “The Cemex Way” case study and how it played a role in Globalization. Familiarize yourself with the Cemex case study, and how it played a major role in globalization.,Analysis on”The Cemex Way” case study – Role in globalization,Task 1,Firstly, critically evaluate the strategy used by Cemex to successfully manage their acquisitions. Also, analyse Cemexs approach to strategic change and consider how their organisational context may impact change. Consider the appropriateness and usefulness of at least one change model.,Secondly, how does the company measure growth? Use chapter 8 for core material and select relevant information.,Thirdly, When assessing growth of Cemex talk about 4-5 criteria, but only use 2 in depth. The criterion include as profit figures,current research,,share price, and growth between two competitive companies.,Lastly, how did Cemex diversify? In answering this question, expand geographically and acquisition driven. In addition, ensure concepts have been used within case study.,Task 2,In this task, first identify what has been the success factor of Cemex?,Some of the success factors to choose from include:,Organisational culture and strategic choices ,History and culture,Business units,Business models-value creation,Then, show evidence of critical analysis of strategy to manage acquisitions. Provide limitations of the sued models further guide to this question from case study. Use Chapter 7 -value creation. Additionally, evaluate critically and provide limitations to used theories., Task 3,This task involves identifying one change model that are related with the case study. You will use this change in conducting a comparison. Also, explain what change model entails. Lastly, why Cemex needed to use this model. Some other key aspects to focus on include:,What change is evident from the case study Chapter 15.,What is strategic change,Why is it important?,In conclusion, put emphasis on depth of the assignment and be problematic rather than width. An example being how has Cemex grown? Materials for such question can be found in Chapter 11.,Attachments,Click Here To Download,Computer Science homework help

Cell Membrane Structure Phospholipid Bilayer

Cell Membrane Structure Phospholipid Bilayer. A cell is the basic unit of life, and the cell membrane is an important structure present in all cells, irrespective of whether they are plant cells or animal cells. This structure is a vital component of any cell and it has a variety of important functions. Cell membrane functions include maintaining the boundaries of the cells, thus supporting the contents of the cell, maintaining proper cell to cell contact, regulating the entry and exit of molecules in and out of the cell, etc. Thus, to understand how the cell membrane manages to carry out this procedure, one needs to understand the cell membrane structure. Given below are the various components that comprise the structure of the cell membrane according to the Fluid Mosaic model. The first layer of cell membrane consists of a phosphid bilayer. The phosphate molecules are arranged in such a way that the hydrophilic heads are on the outside, while the hydrophobic fatty acid tails are on the inside, facing each other. The tails of the molecule are said to be hydrophobic and that is why they points inwardly towards each other. This specific arrangement of the lipid bilayer is for the purpose of preventing the entry of polar solutes, like amino acids, proteins, carbohydrates, etc. Thus, the phosphate lipid bilayer is one of the main factors responsible for regulating the entry and exit of molecules in and out of the cell. Integral Membrane Proteins Integral membrane proteins are those proteins that are a part of the cell membrane structure. They are present between consecutive molecules of phopholipids. These fibrous proteins present may span the entire length of the cell membrane. These molecules have important functions, as they serve as receptors for the cell. Some of the proteins of the cell membrane may also enter the cell. Sometimes, a part of the protein molecule is inside and some of it is outside. These kind of protein molecules act as carriers for active transport of substances in and out of the cell. Some of these protein molecules form pores and thus, allow fatty acids and other lipid insoluble in water molecules to pass through. Furthermore, other integral proteins serve as channel proteins as well to aid in selective transport of ions in and out of the cell. Such molecules are visible with the help of an electron microscopy. Other Elements Certain other elements may also be present along the length of the cell membrane, depending on the location and needs of the cell. These structures include globular proteins, which are peripherally placed and are only at times associated with the cell. These protein molecules may even be enzymes or glycoproteins. In such cases, either the cell will have special functions, or the location of the cell may require it to perform certain specific functions. When speaking of plant cell vs animal cell, there is one important structure that is additionally present most of the time in animal cells. These molecules are cholesterol molecules, which aid the phospholipids in making the membrane impermeable to water soluble substances. These cholesterol molecules also stabilize the membrane and provide the cell with a ‘cushion effect’, which prevents it from suffering any major injuries due to trauma and impact forces. Cell Membrane Function Cell membrane is the outer covering of a cell, which keep the ingredients of a cell intact. Apart from that, there are various other functions, that are carried out by this structure. Read on… It is a common fact that cells are the fundamental building blocks of life. These structures form the basic structural and functional unit of any living thing. While some organisms, like, bacteria are single-celled, most other living things are multicellular. In case of multicellular organisms like humans (an adult human has around 100 trillion cells in the body), there are various types of cells, which are assigned different functions. Each cell is made of intricate structures, which forms an interconnected network, which strives to carry out the function of that cell. As the nature of the function of the cells differ, the functions of various parts of the cells too differ. Let us take a look at the various parts of a cell, especially, the cell membrane and cell membrane function. Cell Membrane and Other Parts of a Cell Basically there are two types of cells – eukaryotic and prokaryotic. While plants, animals, fungi, protozoans, etc. possess eukaryotic cells, prokaryotic cells are found in bacteria only. The difference between the two types of cells lie in the fact that prokaryotic cells do not have nucleus (and/or some other organelles) and are comparatively smaller, as compared to eukaryotic ones. As far as eukaryotic cells are concerned, the basic structure includes parts like DNA, ribosomes, vesicle, endoplasmic reticulum (both rough and smooth), Golgi apparatus, cytoskeleton, mitochondria, vacuole, centrioles, lysosome, cytoplasm, plasma membrane and cell wall. While plant cells have a large vacuole and a definite cell wall, animal cells lack cell wall but some may have very small vacuoles. Animal cells do not have chloroplasts too. This article is about cell membrane, which is also known as plasma membrane or plasmalemma. Scroll down for information about cell membrane function. Read more on: Similarities Between Eukaryotic and Prokaryotic Cells Plant Cell vs Animal Cell Plant Cell Organelles What is a Cell Membrane? Cell membrane or plasma membrane is one of the vital parts of a cell that encloses and protects the constituents of a cell. It separates the interior of a cell from outside environment. It is like a covering that encloses the different organelles of the cell and the fluid that harbors these organelles. To be precise, cell membrane physically separates the contents of the cell from the outside environment, but, in plants, fungi and some bacteria, there is a cell wall that surrounds the cell membrane. However, the cell wall acts as a solid mechanical support only. The actual function of cell membrane is the same in both cases and it is not much altered by the mere presence of a cell wall. The cell membrane is made of two layers of phospholipids and each phospholipid molecule has a head and a tail region. The head region is called hydrophilic (attraction towards water molecules) and the tail ends are known as hydrophobic (repels water molecules). Both layers of phospholipids are arranged so that the head regions form the outer and inner surface of the cell membrane and the tail ends come close in the center of the cell membrane. Other than phospholipids, cell membrane contains lots of protein molecules, which are embedded in the phospholipid layer. All these constituents of the cell membrane work jointly to carry out its function. The following paragraph deals with cell membrane function. Read more on cell nucleus: structure and functions and cytoplasm function in a cell. What is the Function of the Cell Membrane? As mentioned above, one of the basic functions of a cell membrane is to act like a protective outer covering for the cell. Apart from this, there are many other important cell membrane functions, that are vital for the functioning of the cell. The following are some of the cell membrane functions. Cell membrane anchors the cytoskeleton (a cellular ‘skeleton’ made of protein and contained in the cytoplasm) and gives shape to the cell. Cell membrane is responsible for attaching the cell to the extracellular matrix (non living material that is found outside the cells), so that the cells group together to form tissues. Another important cell membrane function is the transportation of materials needed for the functioning of the cell organelles. Cell membrane is semi permeable and controls the in and out movements of substances. Such movement of substances may be either at the expense of cellular energy or passive, without using cellular energy. The protein molecules in the cell membrane receive signals from other cells or the outside environment and convert the signals to messages, that are passed to the organelles inside the cell. In some cells, the protein molecules in the cell membrane group together to form enzymes, which carry out metabolic reactions near the inner surface of the cell membrane. Read more on how do enzymes work. The proteins in the cell membrane also help very small molecules to get themselves transported through the cell membrane, provided, the molecules are traveling from a region with lots of molecules to a region with less number of molecules. Biological Membranes and the Cell Surface http://www.uic.edu/classes/bios/bios100/f06pm/plasmamemb.jpg Membrane Functions Form specialized compartments by selective permeability Unique environment Creation of concentration gradients pH and charge (electrical, ionic) differences Asymmetric protein distribution Cell-Cell recognition Site for receptor molecule biding for cell signaling Receptor binds ligand (such as a hormone) Induces intracellular reactions Controls and regulates reaction sequences Product of one enzyme is the substrate for the next enzyme Can “line up” the enzymes in the proper sequence Membrane Structure According to the Fluid Mosaic Model of Singer and Nicolson http://www.uic.edu/classes/bios/bios100/f06pm/fmm.jpg The membrane is a fluid mosaic of phospholipids and proteins Two main categories of membrane proteins – integral and peripheral Peripheral proteins – bound to the surface of the membrane Integral proteins – permeate the surface of the membrane Membrane regions differ in protein configuration and concentration Outside vs. inside – different peripheral proteins Proteins only exposed to one surface Proteins extend completely through – exposed to both surfaces Membrane lipid layer fluid Proteins move laterally along membrane Membrane Lipids Phospholipids most abundant Phosphate may have additional polar groups such as choline, ethanolamine, serine, inositol These increase hydrophilicity Cholesterol – a steroid Can comprise up to 50% of animal plasma membrane Hydrophilic OH groups toward surface Smaller than a phospholipid and less amphipathic (having both polar and non-polar regions of the molecule) Other molecules include ceramides and sphingolipds – amino alcohols with fatty acid chains These lipids distributed asymmetrically Bilayer Formation Membrane components are Amphipathic (having both polar and non-polar regions of the molecule) Spontaneously form bilayers Hydrophilic portions face water sides Hydrophobic core Never have a free end due to cohesion Spontaneously reseal Fuse Liposome – Circular bilayer surrounding water compartment Can form naturally or artificially Can be used to deliver drugs and DNA to cells Membrane Fluidity Membrane is Fluid Lipids have rapid lateral movement Lipids flip-flop extremely slowly Lipids asymmetrically distributed in membrane Different lipids in each side of bilayer Fluidity depends on lipid composition Saturated fatty acids All C-C bonds are single bonds Straight chain allows maximum interaction of fatty acid tails Make membrane less fliuid Solid at room temperature “Bad Fats” that clog arteries (animal fats) Unsaturated fatty acids Some C=C bond (double bonds) Bent chain keeping tails apart Make membrane more fluid Polyunsaturated fats have multiple double bonds and bends Liquid at room temperature “Good Fats” which do not clog arteries (vegetable fats) Cholesterol Reduces membrane fluidity by reducing phospholipid movement Hinders solidification at low (room) temperatures How Cells Regulate Membrane Fluidity Desaturate fatty acids Produce more unsaturated fatty acids Change tail length (the longer the tail, the less fluid the membrane) Membrane Carbohydrates – Glycolipids and Glycoproteins Face away from cytoplasm (on outside of cell) Attached to protein or lipid Blood antigens – Determine blood type – bound to lipids (glycolipids) Glycoproteins – Protein Receptors Provide specificity for cell-cell or cell-protein interactions (see below) Membrane Proteins Peripheral Proteins completely on membrane surface ionic and H-bond interactions with hydrophilic lipid and protein groups can be removed with high salt or alkaline Integral Proteins Possess hydrophobic domains which are anchored to hydrophobic lipids alpha helix more complex structure An Example – Asymetry of Intestinal Epithelial Cell Membranes Apical surface selectively absorbs materials Contains specific transport proteins Lateral surface interacts with neighboring cells Contains junction proteins to allow cellular communication Basal surface sticks to extracellular matrix and exchanges with blood Contains proteins for anchoring The Extracellular Matrix (ECM) and Plant Cell Walls In animal cells, the ECM is a mish-mash of proteins (usually collagen) and gel-forming polysaccharides The ECM is connected to the cytoskeletin via Integrins and Fibronectins Plant Primary Cell Walls for a rigid cross-linked network of cellulose fibers and pectin – a fiber composite Fiber composites resist tension and compression Plant Secondary Cell Walls are further strengthened w/ Lignin Secondary Cell Walls is basically what comprises wood Cell to Cell Attachments Tight Junctions and Desmosomes Tight Junctions are specialized proteins in the plasma membranes of adjacent animal cells they “stitch together” adjacent cells form a watertight cell Desmosomes are specialized connection protein complexes in animal cells they “rivet” cells together they are attached to the intermediate fibers of adjacent cells Cell Gaps PlasmodesmataCell Membrane Structure Phospholipid Bilayer