the plant cell :: essays research papers

The Plant Cell Cell Wall Size: Around 1Â µ Basic Function: * Hold the shape of the cell. * Strengthen the cell. Covering the cell membrane of the plant cell, there is the cell wall. The cell wall is composed of two layers of rigid, hard cellulose embedded in compounds like pectin and lignin. Pores in the cell wall allow molecules to pass through. The cell wall has two parts. The primary cell wall is formed during the growth of the cell. After the cell has stopped growing, a secondary cell wall forms. This secondary wall is made of lignin and cellulose, woven together tightly, to prevent further growth and to form and strong protective barrier. Cytoplasm Size: Unmeasurable Basic Function: * Helps dissolve waste products * Creates a "medium" for vesicles to travel through * Aids in cell metabolism * Serves as a home for the cytoskeleton. The cytoplasm is the jelly-like material that makes up much of the cell. It is 80% water and usually clear in color. It also contains many salts. The liquid portion is referred to as cytosol. In fact, "cytoplasm" means "cell substance." The cytoplasm is also the home of the cytoskeleton, a network of cytoplasmic filaments that are responsible for the movement of the cell. The cytoplasm is constantly moving and churning due to cytoplasmic streaming. Golgi Apparatus Size: Between 2 and 3Â µ Basic Function: * Serves as "processing center" for cell. * Packages and processes new proteins. * Prepares proteins for secretion or storage. The Golgi Apparatus is a series of stacked membranes in the cytoplasm that packages proteins for secretion or storage in vesicles. Inside the membranes are sacs of fluid or gel-like substances. The Golgi Apparatus takes proteins in transport sacs from the endoplasmic reticulum and sends it through a series of these membranes. The proteins are then "modified"' as they pass from membrane to membrane. After the vesicle of proteins has finished its trip through the Golgi Apparatus, it buds off the organelle in a Golgi sac, ready to be stored or transported to other parts of the body. Cell Membrane Size: 7 to 8 NM (nanometers) Basic Function: * Controls what enters and exits the cell. * Separates cell from outer environment. On the outside of all cells, there is a layer of protein and lipid (fat) called the cell membrane or the plasma membrane. This membrane is found in ALL cells. The membrane is selectively permeable, meaning it allows some molecules to enter and some not to. The membrane allows molecules in through two forms

Does language affect thought? Essay

Thinking is possible without language because expressing a thought is often limited by words. As the famous saying says â€Å"a picture is worth a thousand words† this may also mean an idea a though or a picture in your mind, is worth a thousand words. Many times, people would like to express something they are imagining in their minds but do not have or know the right words to do so. Languages can create perspectives and be a mean to express and receive thoughts; however, thinking does not always require language. Language facilitates knowledge by not only giving us a way to express it but also providing us with a way of imagining something. It allows us to organize and simplify our ideas. For instance, it is easier to think in a table as the word â€Å"table† instead of imagining the entire three dimensional objects. A good example of this is a history book: through its words (language) it gives us a, sometimes clear, picture of a battle, a signing of a treaty or any historic event. Through its words the book is able to provide the reader with knowledge which is then transformed by the reader into an idea and a thought. The same can happen inversely, a though can be converted into language, as people do in everyday conversations. While this might be true, it does not mean that people cannot think, know, or have an idea without using language. A good example that proves this is a newborn; a baby that is hungry and wants milk, even though he does not know the words to express it, must be thinking â€Å"I am hungry† or â€Å"I want milk†. Some may argue that a baby’s hunger is an instinct, not a though, but in some cases kids do not learn how to speak until they are much older, does this mean they have lived on only instincts and not thoughts until they learned to speak. But children learn words little by little, not all at once which may lead the questions, where is the boundary? How much language must someone know to be able to think? Or, Can people only think the words you know? Is a baby’s first though â€Å"mommy† or â€Å"daddy†? Even though babies have not learnt any form of communication, they laugh think something is funny. Languages can extend knowledge and bring new perspectives together. To efficiently use 100% of language, you would have to know every single word of every single every language, but let’s keep it down to only English. English has an extensive vocabulary; the more English you know the more you expand your thoughts, since better use of language means thoughts can be expressed more accurately. Knowing the right words to put forth a thought is vital in order to let another person understand what you are thinking. This is evident when people struggle to say or write something because they cannot come up with the appropriate word or words to express their exact thoughts (as I have been doing while writing this paper). This leads us to further evidence that thinking without language is possible; when people fail to find appropriate words for any thought, it proves they their not able to put their thought into language. The thought is not put into language by its owner because it is not fully expressible through the language he knows, and even though he does not know the words the express his thought, he is still thinking it. Also, often, as time passes, new words are constructed to express new thoughts meaning the existing vocabulary is inadequate to express the thoughts you have. This indicates that language is created by thoughts, and to extend language, thoughts must already exist before they can be put into a language. As language is broadened by thoughts, people grow to become more restricted to language. Basically, once you know words, it is very difficult to think without using them; when you see the color white, you think â€Å"white†, when you see a ball, you think â€Å"ball†, when you see the sky, you think â€Å"air†, â€Å"blue†, â€Å"sun† and so on, all in the form of words. Language only restricts a thought to one way of thinking and limits it from expressing the thought to the full extent. While there is no limitation placed on thinking by language, because thinking does not necessarily require language. Thinking does not always require language; people are capable of thinking without language. When most people think rationally, they require language. When people think or even talk within themselves they do it through language. But when people think visually they do not need language to give them information about the visual world. For example; someone can look at a person’s face and know what they are feeling. Language is a mean of receiving or expressing though, it is not the though itself, thus if you do not have to receive or express a though, you do not need language, which leads to the conclusion that it is possible to think without language.

Francis Bacon on Youth and Age

Francis Bacon  was a true Renaissance man—statesman, writer, and philosopher  of science. He is considered the first major English essayist. Professor Brian Vickers has pointed out that Bacon could vary the tempo of argument in order to highlight important aspects. In the essay Of Youth and Age, Vickers notes in the introduction to the Oxford Worlds Classics 1999 edition of The Essays Or Counsels, Civil and Moral  that Bacon uses a most effective variation in tempo, now slowing down, now speeding up, together with syntactical parallelism, in order to characterize the two opposed stages of life.   Of Youth and Age A man that is young in years may be old in ​hours, if he have lost no time. But that happeneth rarely. Generally, youth is like the first cogitations, not so wise as the second. For there is a youth in thoughts, as well as in ages. And yet the invention of young men is more lively than that of old, and imaginations stream into their minds better, and as it were more divinely. Natures that have much heat and great and violent desires and perturbations, are not ripe for action till they have passed the meridian of their years; as it was with Julius Caesar, and Septimius Severus. Of the latter of whom it is said, Juventutem egit erroribus, imo furoribus, plenum1. And yet he was the ablest emperor, almost, of all the list. But reposed natures may do well in youth. As it is seen in Augustus Caesar, Cosmus Duke of Florence, Gaston de Foix, and others. On the other side, heat and vivacity in age is an excellent composition for business. Young men are fitter to invent than to judge; f itter for execution than for counsel; and fitter for new projects than for settled business. For the experience of age, in things that fall within the compass of it, directeth them; but in new things, abuseth them. The errors of young men are the ruin of business; but the errors of aged men amount but to this, that more might have been done, or sooner. Young men, in the conduct and manage of actions, embrace more than they can hold; stir more than they can quiet; fly to the end, without consideration of the means and degrees; pursue some few principles which they have chanced upon absurdly; care not to innovate, which draws unknown inconveniences; use extreme remedies at first; and that which doubleth all errors, will not acknowledge or retract them; like an unready horse, that will neither stop nor turn. Men of age object too much, consult too long, adventure too little, repent too soon, and seldom drive business home to the full period, but content themselves with a mediocrity of success. Certainly it is good to compound employments of both; for that will be good for the present, because the virtues of either age may correct the defects of both; and good for succession, that young men may be learners, while men in age are actors; and, lastly, good for extern accidents, because authority followeth old men, and favour and popularit y youth. But for the moral part, perhaps youth will have the pre-eminence, as age hath for the politic. A certain rabbin, upon the text, Your young men shall see visions, and your old men shall dream dreams, inferreth that young men are admitted nearer to God than old, because vision is a clearer revelation than a dream. And certainly, the more a man drinketh of the world, the more it intoxicateth; and age doth profit rather in the powers of understanding, than in the virtues of the will and affections. There be some have an over-early ripeness in their years, which fadeth betimes. These are, first, such as have brittle wits, the edge whereof is soon turned; such as was Hermogenes the rhetorician, whose books are exceeding subtle; who afterwards waxed stupid. A second sort is of those that have some natural dispositions which have better grace in youth than in age; such as is a fluent and luxuriant speech, which becomes youth well, but not age: so Tully saith of Hortensius, Idem man ebat, neque idem decebat2. The third is of such as take too high a strain at the first, and are magnanimous more than tract of years can uphold. As was Scipio Africanus, of whom Livy saith in effect, Ultima primis cedebant3. 1 He passed a youth full of errors, yea of madnesses.2 He continued the same, when the same was not becoming.3 His last actions were not equal to his first.