Why Cells Are Small Essay Example For Students

Why Cells Are Small Essay annonCells are the basic structural and functional units of life. As life onearth has evolved into organisms of varying complexities, two basic lawsof nature have dictated why cells have remained so small. Shorter isfaster. This is true both in terms of diffusion and in terms of chemicaland electrical movement. By minimizing the the distance between a cellsnucleus and and the numerous proteins and organelles that it mustconstantly regulate , a cell is maximizing the speed in whichintercellular communications can take place while providing the idealconditions for diffusion: a vital function in the life of a cell. Likewise, the surface area and volume of a cell are directly influential inthe efficiency of the cells nutrient absorption and waste expulsionprocesses. Since the cell membrane of a eukaryotic cell is its onlysource of nutrition, its surface area must be large enough to allow thecells organelles to receive the materia ls it needs. This is done bymaximizing the surface area to volume ratio. By using the surface areaand volume equations for a sphere(4r2 and 4/3r3) you can estimate thesurface area of a small cell(5 m) to be nearly 1,200,000 : 1. Bymodeling the growth rate of the surface area and volume of a sphere on alinear graph its easily discernible that as the size of the sphereincreases the ratio of surface area to volume dramatically decreasesuntil finally the volume of the sphere surpasses the surf ace area. We will write a custom essay on Why Cells Are Small specifically for you for only $16.38 $13.9/page Order now Simply, by minimizing its size, a cell is maximizing the speed at whichit can communicate, the rate at which diffusion can occur, and the amountof surface area at its disposal. Daniel VeilleuxJune 17, 1976Period 5

Slowing Revelotion essays

Slowing Revelotion essays Technology, a progressive tool in the last decade! Every day technology influences many Americans in their daily living, from cell phones, microwaves, CD-players, home personal computers, to lap top computers technology has made the American standard of living easier and convenient. In the last decade technology has affected many components in our American culture. The President of the United States Bill Clinton has deemed one of these components as the New Economy. The New Economy is the information technology revolution that has changed the way America does business, and has changed our market and others around the world. Can the market depend on the information technology revolution to be as prosperous in the future? What factors contributed to the New Economy? In the early 1990s technology was knocking at the doors of every Americans home. Affordability and convenience is what lead to the rebirth of the economy. Personal computers or PCs for short were much more obtainable in the early 90s, with more Americans with computers in their homes Americans became one with technology. The growing popularity of PCs led to the biggest benefactor in our economic revolution, the Internet. Today the Internet is household terminology; daily business of all sorts is performed on the Internet by all ages in the world. Users can access personal mail through e-mail, read headline news, research anything, and shop for goods and services from the comfort of home. Around 1995 the Internet Boom was recognized, the Internet became a huge shopping mall for consumers. According to Paul Kedrosky writer for the Wall Street Journal, there is an estimate of 10 million web pages on the Internet. This immense amount of growth in the Internet industry has been a key element in our economic prosperity. Many businesses have had significant gains financially in the dot-com i...

How to Get a Job as an Online High School Teacher

How to Get a Job as an Online High School Teacher Teaching online high school courses can be a full-time profession or a rewarding way to supplement your income. New online high schools start up every year, and qualified online teachers are in high demand. Typically, virtual instructors are expected to monitor students in several courses, grade assignments, interact through message boards or emails, and be available when students have questions. The curriculum for online high school classes is often pre-determined by the school and online teachers are generally expected to follow a particular syllabus for each course. How to Qualify for Positions Teaching High School Online Online charter schools are publicly funded and must follow some state and federal guidelines. Generally, online teachers hired by charter schools must have a valid teaching credential for the state the school is based in. Private and college-sponsored schools have more flexibility in hiring, but they also tend to favor online teachers with credentials or an impressive work history. The best online high school teachers usually have classroom teaching experience, technological competency, and excellent written communication skills. Where to Find Online High School Teaching Jobs If you want to become an online high school teacher, start by looking for jobs locally. Contact the online charter schools in your district to see if they are hiring, send in your resume, and be prepared for an in-person interview.Next, take a look at online high schools that enroll students in multiple states. Large online charter and private schools generally accept applications through the internet. Programs such as K12 and Connections Academy have streamlined application processes. Finally, try applying individually to smaller online private schools throughout the nation. Some of these programs offer online job information; others require potential employees to research the appropriate contact info and make a few phone calls. How to Stand Out as a Potential Online High School Teacher Your application probably won’t be the only one sitting on the principal’s desk. Stand out from the crowd by emphasizing your teaching experience and your ability to work in an online environment.During the application process, keep deadlines and respond to phone calls and emails promptly. Keep emails professional but not overly formal or stuffy. Resolve any technical problems (such as email attachment issues or difficulty accessing online application materials) quickly. Since ​online teaching jobs are all about virtual communication, consider every interaction with the school an opportunity to prove yourself.

The Marketing Mix Research Paper Example | Topics and Well Written Essays - 500 words

The Marketing Mix - Research Paper Example This paper will describe the four Ps in the marketing mix for Sun Chips by Pepsi Company. The product is one of the critical elements of the marketing mix. It places emphasis on the product design and how it meets the needs of the customers. With increasing competition in the business world, companies focus on unique product designs with features that appeal to the customers. The Pepsi Company has relied on innovation to make healthy products that are environmentally friendly as well. Moreover, the Sun Chips are unique because they are made from corn and wheat using the solar energy. The fact that the Sun Chips define a healthy snack available for many Americans makes it a preferred product by customers who are aware of their healthy eating needs. Notably, the Sun Chips pack its products in bags of a material that decomposes easily (Ferrell and Hartline 61). This exhibits the company’s commitment to environmental sustainability. Since Pepsi’s Sun Chips are as general foods, they are available in retail shops in different states. The availability of the product in close proximity to the customers is an advantage for the company. This is because customers in need of the product can purchase it at once at the nearest retailer shops. Moreover, customers can interact with the sales and the marketing team on the company’s website. However, this is convenient for wholesale buyers who need the product in bulk. The company owns its distribution channels, a factor that ensures that it has en evident control over the availability of its products in different stores (68). The Pepsi Company as relied on television advertising for a long time. However, it seems to be embracing technology by venturing into e-marketing as well as online promotions available at the company’s web site. This ensures that more people are aware of the company’s products a factor that is likely to increase sales. Effective promotion is of critical importance in an effort to

Critically discuss the empirical evidence that there are sex Essay - 1

Critically discuss the empirical evidence that there are sex differences in intelligence - Essay Example Rather, it reflects a broader and deeper capability for comprehending our surroundings—"catching on", "making sense" of things, or "figuring out" what to do. (p.13) The complex factors that affect intelligence have fascinated researchers over the years, with the belief that gender plays a significant role in cognitive abilities. In an effort to settle controversies concerning gender and intelligence, empirical researches in the fields of psychology and learning have made attempts to identify how the two sexes perform in certain cognitive tasks. Based on the results of the standardized measures in cognitive batteries, increasing evidence from various studies confirm that men’s functioning and women’s functioning are in fact different. A study conducted by Jackson and Rushton (2005) investigated the sex differences in general mental ability. A Scholastic Assessment Test was given to 100,000 high school graduates where results showed that the male samples performed better with an average IQ score of 3.63 higher than the females. This finding was consistent with other factors across groups such as gender differences in gene ral mental ability for participants from different socioeconomic levels and ethnic groups. Likewise, the British Journal of Psychology published the findings of a study made by Lyn and Irwing (2005) on a big sample of university men and women. The controversial research that aroused public attention indicated that based on IQ, men’s average scores were higher between 3.3 and 5.0 than women. While outcomes of these research studies have favored the male sample, results of other studies revealed that although both male and females vary on average in how competently they function on different skill tests, cognitive skills are actually equally distributed between them (Halpern, D.,Benbow, C., Geary, D., Gur, R., Hyde, J., and Gernsbacher,M., 2007). For instance, women are likely to achieve higher scores on specific verbal

We Need an Amendment Outlawing Flag Desecration :: Argumentative Persuasive Argument Essays

We Need an Amendment Outlawing Flag Desecration In an attempt to make outrageous political statements, people often go to extremes: monks burn themselves to express freedom from religious intolerance, civilians stand in front of military tanks to stop them from destroying their city, and others burn or tear up flags to demonstrate their beliefs on issues from racism to war. Although flag desecration is the least violent of these three examples, it should be banned with an amendment because the flag is a symbol of freedom. Flag defilement is seen in many forms, such as- spitting on, tearing apart, or burning. During the 1960’s, a time of despair and revolution, flag vandalism proliferated. In effort to alter their lifestyle, Americans stampeded the streets ruining the symbol of freedom in the name of politics and racism. The violent array of insubordination created an immediate reaction. Each protest became more violent and ill mannered. Each time someone demolishes a flag, the act is not freedom of speech- it is an expression of an anti-American lifestyle. During the Vietnam War, activists ironically demolished the flag to bring back the men fighting overseas. The same men who were fighting for the freedoms of Americans and the symbol of America. These soldiers believed in America as a country and the flag as a badge of democracy and freedom so much, they risked their lives and almost 60,000 American soldiers died to preserve America’s freedoms. Those who have lost family members in a vicious battle will understand that it is not a sign of admiration to disgrace the icon for which these young men died to defend-- many between the ages of 17 to 24. In honor of those who may die for our country in the future, the Senate should pass an amendment outlawing flag desecration. As a daughter of an American soldier– who fought in both

Phi Delta Kappa

Phi Delta Kappa is an international organization for professional educators. The organization's mission is to promote quality education, with particular emphasis on publicly supported education, as essential to the development and maintenance of a democratic way of life. Each year Phi Delta Kappa conducts a Gallop Poll to see the publics view toward Public Schools. The poll tackles many different issues that are important in their own way, but the ones that interest me the, favoring or opposing a voucher system, zero tolerance polices, and school standards. One of the most controversial issues in the gallup poll is the usage of vouchers as a means of improving the quality of the public schools. It is suggested that doing so will promote competition between public and private schools and that competition will bring about improvement in the public schools. Opponents of the voucher plan believe that being able to use vouchers for religious schools will violate the separation of church and state established by the First Amendment to the U. S. Constitution. In addition, parents might be forced to send their children to a school of a different religion because no other schools are available. The result of the poll show that 47% favor vouchers, 48% oppose them and 5% don†t know. I am surprised that so many people support vouchers when there is no proof that private schools improve students academic achievement. Competition between public and private schools could affect the salaries of presevice teachers and whether or not a teacher can be hired in private schools because of their religion. The best public policy is to provide parents with even more choices within the public schools, which serve over 90% of children. Legislators should concentrate on making all public schools stronger, safer, more challenging, and accountable. Public tax dollars should be spent only to improve public schools – not to assist the limited numbers of parents who choose to enroll their children in private secular or religious schools. Concern over school crime and violence has also become a huge issue. It has prompted many public schools to take various measures to reduce and prevent drugs and violence and to ensure safety in schools. Such measures include adopting zero tolerance policies. The zero tolerance policies enact mandatory expulsion for violent or drug-related student misconduct. This forces preservice teachers to change the disciplinary structure of the classroom. The poll shows that 90% of the people favor zero tolerance and 10% oppose it. I feel that zero tolerance, as explained in the reading, is a fantastic thing. But when hearing about students suspended for having aspirin or even cough drops, leaves me to wonder whether zero tolerance policies are achieving their designated purpose. The response to zero tolerance by school districts is getting out of hand. Schools need to make sure that their focus is not on blind enforcement of a rule but on actively working to detect warning signs, counsel students and punish those involved with real drugs or weapons. A third critical issue is school standards. Achievement standards in the classroom is a very important thing. 57% of people think that the standards are about right and 33% think they are too low. Another issue about standards is social promotion. Social promotion means moving children from grade to grade in order to keep them with others in their age group. 2 % favored stricter standards for social promotion and 26% opposed. I agree with the majority in both these cases. School standard are about right but it is important for preservice teachers to know and keep up with the standards. It is also important for teachers to have stricter standards for social promotion even if more students are held back. It isn†t fair to send a slacking students to the next grade to another teacher that has to re-teach the curriculum of the previous grade just for a student to two. My view on vouchers is pretty clear. People who support them believe that it will improve public school because of competition. Competition is based on an even playing field; there is no fair competition when â€Å"competitors† play by different rules. Public schools have to accept all applicants; private schools don†t. Private schools are not required to provide transportation, special education, bilingual education, free and reduced lunches, and many other programs that public schools provide. I agree with zero tolerance but they are taking it too far. I can also understand the schools' rationale for zero tolerance. They are concerned about student safety and want to project the image that they are being tough on drugs and violence, but use some common sense. When it comes to the standards of student achievement I agree with the majority of the people polled, but many of the issues of the Phi Delta Kappa Gallup Poll I disagreed with because I feel that the people being polled are uneducated in the subject and don†t know how their opinion can affect schools.