Architecture Of Renaissance Period - Free Essay Example

Sample details Pages: 6 Words: 1843 Downloads: 7 Date added: 2019/06/14 Category Art Essay Level High school Tags: Renaissance Essay Did you like this example? Location, Continent, Country/City Renaissance architecture originated in Florence Italy in the 15th century but once the style appeared in other Italian towns, it began to make appearances in France, Russia, England, and other parts of Europe. Although it moved to other countries, the influence was less significant than in Italy. Time Period and Related Artistic Styles The new style of architecture is known as the style that replaced medieval Gothic. Renaissance architects used the basic design element, order, and found a relationship between human proportions and buildings and this was a nod towards both Greek and Roman architecture. Using these proportions, the buildings became comprehensible spaces which is a distinguishing feature from the once known Gothic style. Don’t waste time! Our writers will create an original "Architecture Of Renaissance Period" essay for you Create order Environment Before the Renaissance Era, it was the Medieval Times. During the Dark Ages, famine broke out, war, and diseases. The Black Plague had spread throughout Europe killing about 60% of the continentrs population, but because of the disease, Italy made changes in their trades and businesses and sold leather goods, cheese, and wines. The working class became wealthy due to the trade and the Italian cities became widely popular. It was the men like Leonardo Da Vinci, Leon Battista Alberti, Cola da Caprarola, Donato Bramante, and Filippo Brunelleschi that came to the ideas of proportions, order, and balance of the existing world and incorporated it into the structural, architectural world. Culture As mentioned, it was various men who impacted and supported the new Renaissance Era. There were issues with the economy, the current architectural buildings (Gothic), and they believed there were better ways. Renaissance means rebirth and was created because of the corruption of the Catholic Church. The old ideas of the Greek and Roman provided the people with the answers that they believed the church could not and it was considered to be the reawakening of these ideas. Renaissance reconception of architecture was the return to the classical language, which had a vocabulary of elements based on orders, and a set of rules, and within the new Renaissance way of design thinking, the mind of the designer was equally apparent, so much so that his personality could, and even should, show through in his finished work (2). Politics Leon Battista Albertirs design of the church of S. Francesco, located in Rimini, was built in 1450. The church was a centrally planned and was inspired by ancient architectural philosophies, Greek and Roman. Alberti wrapped a previous building with a new wall to reconstruct a classical building utilizing arches, and a triumphal arch much like Roman Architecture. The architects, McKim, Mead, and White drew inspiration from Albertirs classical style when building the Boston Public Library, in the nineteenth century. The Boston Public Library was planned around a central courtyard, similar to S. Francesco and the exterior of McKim, Mead, and White also drew heavily upon the Albertirs idea heavily implementing the use of arches and vaults. The Renaissance style has been used in large cities such as San Francisco, New York, and has influenced various government buildings in Washington DC. Renaissance style and techniques used in these historic buildings can be seen in modern day buildings . Section II Architecture and Design Provide Three Characteristics Renaissance architecture is mainly derived from both Greek and Roman architecture. Humanism is the idea that you feel like you can aspire to do anything by learning and having a good education and this was very important to all three styles. Another big part of all three styles is the interaction between Man and structures. While Greek and Roman styles had the biggest influence on the Renaissance, Gothic architecture also played a role. Renaissance designers (much like Leon Battista Alberti) wanted to move away from the previous style, however, Gothic architecture also used man-like techniques to measure out space and materials; it is where the expressions a thumbnail, at arms length, and a foot derived from. Difference is, that Gothic architecture used someone different each time and there was no exact measurement for these sayings, but the Renaissance style took those sayings and made them into something specific. Specifically, Renaissance uses the arches, humanism, and corinthian columns that was used in both Greek and Roman architecture; there was no Renaissance building that is a copy of an ancient precedent, no painting or sculpture that looks like Roman or Greek. Details might be imitated, concepts rediscovered, but the Renaissance always generated new synthesis from the knowledge that came from study of ancient classism (1). Provide at Least Three Descriptors S. Maria della consolazione interior has a centralized square plan, with three polygonal apses and one semi circular. Each are capped by semi circles and the central square becomes a cube capped by a large interior dome. The church and the convent was built by Guiniforte Solari but was modified by Bramante in the late 15th century. Bramante enlarged the church by adding a large semi-circle apse, a cloistered a refectory, and a drum shaped come that is surrounded by columns. Furniture from Palazzo Davanti (bedroom) has been fully preserved and well taken care of. Most renaissance furniture is made of wood (oak, walnut, or cypress). Canopy beds were used for both warming reason and privacy, but these beds along with chairs, were not considered comfortable. In the renaissance convenience was more important than practical. Davanzati bedroom is elaborate. The ceiling has exposed wood which is covered in a decorative pattern and the floor is tiles. The walls are covered in frescors and the overall feeling of the room is warmth. Furniture if minimal but there are the essentials, bed, dresser, baby cradle, table, and chairs. The baby cradle is also made out of wood and could be moved throughout the room (either close of further away from the fireplace or master bed). The last pieces in the bedroom are two chars, a table and a dresser. Over the dresser is some painting of a significant religious characters and it was common that bedrooms had fireplaces in the co rner for the cold winter months. The table and chairs were used as a way to display and work on writing pieces and reading. During the Renaissance one could not brag about their wealth, therefore they would leave their studies out on tables as a way to demonstrate their intellect. Medicine and astronomy were common in households. Astronomy was used for telling time and the wealthier an individual was, the more access they had to these instruments. The armillary could be used to cast the horoscope at the birth of a child and astrology provides the link between health and the heavens, and not only through the predictive power of the horoscope / A physician was trained in consulting the heavens for predicting the course of disease and determining the most propitious time for therapeutic intervention (3) As mentioned, in furniture, wood was commonly used. However, these instruments were typically made of brass, gilt brass, and more rarely, silver. Provide Three Characteristics Renaissance design has influenced many pieces of architecture and interior designs since it became a style. French architect, designer, and inventor Philippe Starck is derived from Renaissance style. He focuses on how the essentials are important, the relationship between Man vs. nature, and he claims that everything should be organized to the needs of human bodys. As well as influencing specific designers as previously mentioned, the style has influenced the Boston Public Library, churches and cathedrals in large cities, Government buildings in Washington DC, and residential homes are sometimes decorated in the Renaissance style. Materials Furniture was commonly made out of wood. Chairs, beds, and chest would have wood carvings depicting a religious scene, and hints at its reflection on both Greek and Roman architecture. An example of a piece of furniture that is made of wood and has gilding is a Lacquered and gilded games table, with detachable top of lobed oval outline, painted with birds and flowers, with shaped frieze containing two drawers on bold cabriole legs painted and mounted (4). Along with furniture, Rosary beads were also made out of wood and gilded gold. Brass was used for the more expensive decorative arts. Motifs In the S. Maria della consolazione church interior on the north wall is The Last Supper painted by Leonardo da Vinci. The conversation that is depicted in Da Vincis photo is the moment right after Christ said One of you will betray me. Each of the 12 Apostles in the painting are depicted with different movements and expressions and therefore his painting is known as one of the masterpieces of the world and has had a great deal of influence over the figurative art style. The furniture from Palazzo Davanti bedroom does have carvings in the wood Construction Techniques Wood was a generally easy medium to work with and was the most common material used in Renaissance furniture. In the construction of cassones, chairs, tables, beds, corner cupboards, and game table, these walnut, cypress, and oak pieces were shaped, carved, and built into fabulous pieces that then were ornamented with gild, gold, ivory, frieze, scrolls, and more. One major item in minute detail After getting guidance from Brunelleschi, painter Masaccio created a fresco painted called the Holy Trinity at S. Maria Novella in Florence. Brunelleschi found the way to take a three dimensional object and replicate it exactly on a two dimensional surface, convincing the illusion of space. The painting depicts God standing on a sarcophagus holding the crucified Christ while S. John and Mary are standing in front of two kneeling donors. The donors were not allowed to be in the recessed space where the biblical characters are depicted near the cross, they were purposefully painted to appear in the space of the viewer. One-point linear perspective is the technique that gives the sense that the painting receded back into space. Renaissance art and architecture focus on proportions and symmetry, and the composition of this painting is in a pyramid shape, much like the panel of bronze doors competition Brunelleschi entered in for the Florence Baptistery. Renaissance style is a reflection of Roman and Greek classical architecture. In the painting a coffered ceiling, barrel vaults, columns, and pilasters are depicted which were substantial in Roman architecture specifically. Using the one-point perspective technique in the coffered ceiling, creates the vanishing point which is located at the bottom of the cross. This is what causes the painting to look as though it is receding into the chapel. Finally, at the bottom of the fresco is a skeleton in a tomb. Until recently, this part of the fresco was covered. The tomb was painted with the intentions to look as if it was three dimensional and coming at an outward projection. Above the tomb are words that have been translated to What you are I once was; what I am, you will be. This is a portrayal of death and that it is destined for everyone. Above the crucifiction there is a message of hope, freedom from death for believers. The complex painting is an example of a biblical story, science, and art all in one.

Essay on The Third Gender - 1662 Words

Kaleen Rodriguez ENC 1102 Exploratory Essay The Third Gender What is the role of the third gender in South Asia? How does Asian society identify the third gender? I walked into my best friend Joel’s room this morning extremely excited to have lunch with him after a long four months without seeing him and on my journey to his room I picked up a paper that was lying by his door. I picked it up and the title was â€Å"Hijra† as I continued to read this paper, it had me very intrigued, fast. It so happens that earlier that week I was talking to my mom about Pride Fest which is a LGBT festival here in South Florida. So, my question arose, how do others across the world view what we recognize as the LGBT community†¦show more content†¦I wanted to see Hijra’s what they looked like, their gestures and all. I decided to YouTube a video on them and I was able to find it and many different answers to my question above. It came to my attention that more than half of the Hijra’s documented have been att racted to men from a very young age, or so they say. The first Hijra in this YouTube video began her story by saying that she always admired the woman lifestyle, wearing the gem in the middle of their eyebrows the clothing attire also known as a saree and as she grew up her walk became more feminine and the way she spoke only followed, basically insisting that she was born in the wrong body. Although, the other small percent in this video mostly agreed that as they grew up and were raised as a male, they just wanted to be like a woman but they are clear on the fact that they were or are men (Ambujablues Channel). Becoming more engaged in the Hijra lifestyle I googled as a form of research and I simply typed in â€Å"Hijra Culture† the first thing that arose was a link to a slide show done in 2007. Here I found the history of Hijra’s regarding the Karma Sutra (an ancient Indian text), which is said to have mentioned a third gender (Gueste0d1c4). This to Hijra’s must mean the world, mostly because it somewhat proves that they’re not just getting the transgender idea from the western culture, but that it has existed in the Indian culture long before. Being a Hijra was said to be a disturbing viewShow MoreRelatedThird Gender1599 Words   |  7 Pagesjustification for aligning them with different social roles which restrict and mold their attitudes and behavior. Merriam-Webster defines gender as the behavioral, cultural, or psychological traits typically associated with one sex. Narrow minded society of today is not satisfied with the natural difference of sex, but eac h insist on adding a cultural difference of gender to it. The unsophisticated, ideal physical facts always become associated with the complex psychological qualities (Holter). It is notRead MoreAndrogyny And The Third Gender Essay1813 Words   |  8 PagesAndrogyny and the third gender are present in many cultures and each combination of masculine and feminine qualities make it a unique phenomenon that is on an individual basis. Since ancient times to present day, the idea of the third gender has been discussed by many scholars, as well as what gender truly can be defined as. It is undeniable that androgyny has become more mainstream as of recent, especially with help from the fashion industry in the early 2000s when they began to employ androgynousRead MoreMexican Culture and the Third Gender634 Words   |  2 Pages Summary Alejandro Taledo is known as Alex. Although Alejandro is a boys name, Alex is a girl. She was born a boy, but she identifies with being a girl and other people also see her now as her chosen gender. She works with her mother during the day, selling flowers. Alex is not alone in Juchitan. A town in Oaxaca, Mexico, Juchitan has a high concentration of transgendered individuals as well as gays and lesbians. The town is also known for its beautiful black pottery and traditional food. AlthoughRead MoreThe Third Sex in Eastern Civilization1357 Words   |  6 Pageslooking at certain topic such as Gender, sex and religion. Gender is defined as the cultural, behavioral, or psychological characteristics, typically belonging to one sex. Sex is the behavioral, functional and Structural characteristics that distinguish males from females; it is also the act of people (or animals) attempting to sexually reproduce. Western civilizations and religions have always been strict and less accepting when it comes to the conversation of gender and sex. It is usually somethingRead MoreThe Importance Of Language As A Tool For People995 Words   |  4 PagesBefore taking this class, I had some basic knowledge about genders and sexualities because I accidently took the junior cluster class instead of the sophomore inquiries when transferred to Portland State University. In the beginning of the quarter I was not interested because I thought I was going to be a repeat of junior cluste r but I was wrong. I got to learned a lot during this class. This class was more discussion based whereas my other class was all theory and tests. I really enjoyed this classRead MoreSexuality Is A Social Identity That Goes Beyond The Objectivity1636 Words   |  7 Pagesindividuals, which in turn fabricate the social constructivism of a nation. Classism, heterosexism, and cisgenderism are further reinforced within the institutionalization of heteronormativity, being the promotion of the gender binary and heterosexuality as the only valid form of gender expression and sexual orientation. The normalization of this system is not enforced as inconspicuously as one would believe, with both Western and Eastern countries visibly dictating social norms in regards to sexualityRead MoreShakespeare s Twelfth Night : Gift Exchange, Debt And The Early Modern Matrimonial Economy1321 Words   |  6 Pagesand gender identity became a more acceptable concept.However, even though it became accepta ble once again in the twenty first century. Literature throughout the ages depicted different sexual orientation and gender identification. The play Twelfth Night made produced by William Shakespeare discusses the topics of sexuality during the early 17th century. The articles Gender Trouble in ‘Twelfth Night by Casey Charles agrees that the main central theme of this play is associated with gender identificationRead MoreTransgenderin India - Gender Inequality Point Of View ..2514 Words   |  11 PagesTRANSGENDER IN INDIA - GENDER INEQUALITY POINT OF VIEW MR. ABILASH CHANDRAN Asst. Professor. Department of Social Work, Christ College (Autonomous) Irinjalakuda, Thrissur, Kerala, India. abilashmsw@gmail.com 9544214227 MS. KEERTHANA VIJAYAKUMAR Master of Social Work 3rd Semester, Department of Social Work, Christ College (Autonomous) Irinjalakuda, Thrissur, Kerala, India keerthanaviyyur@gmail.com 70250489 Paper abstract: Gender inequality perspectives of the third gender/ transgender in IndiaRead MoreThe National Legal Services Authority Essay1930 Words   |  8 Pagesnational legal services authority filed a case for violation of their legal rights. Then the supreme court of India passed a judgment regarding transgender community for the legal declaration of their legal rights. They pray that non-recognition of their gender identity violates article 14 and article 21of the constitution of India. CASE FACTS: This case is mainly concerned with transgender community and their issues. The national legal services authority constituted under the legal services authority actRead MoreProblems with the Gender Binary System2323 Words   |  10 PagesAcross the globe, gender systems vary in ways that often exclude individuals who don’t identify within their realms. From the binary structure of the West, to the ternary system of India, there are many ways in which societies conceptualize gender. Gender systems are generally considered inherent to humanity, and are seldom questioned or altered. This has led to the marginalization and discrimination of individuals who diverge from the implemented structure. The gender binary of Western culture

Metabolism Free Essays

The life support activity of even the most structurally simple organism involves a large number of complex biochemical reactions. Most, although not all, of the biochemical processes of bacteria also occur in eukaryotic microbes and in the cells of multicellular organisms, including humans. However, the reactions that are unique to bacteria are fascinating because they allow microorganisms to do things we cannot do (Neidhardt Holde, 1990). We will write a custom essay sample on Metabolism or any similar topic only for you Order Now For example, some bacteria (the chemoautotrophs) can grow on diets of such inorganic substances as carbon dioxide, iron, sulfur, hydrogen gas, and ammonia. This paper examines some representative chemical reactions that either produce energy (the catabolic reactions) or use energy (the anabolic reactions) in microorganisms. We will also look at how these various reactions are integrated within the cell. II. Discussion A. Catabolic and Anabolic Reactions We use the term metabolism to refer to the sum of all chemical reactions within a living organism. Because chemical reactions either release or require energy, metabolism can be viewed as an energy-balancing act. Accordingly, metabolism can be divided into two classes of chemical reactions—those that release energy and those that require energy. In living cells, the chemical reactions that release energy are generally the ones involved in catabolism, the breakdown of complex organic compounds into simpler ones. These reactions are called catabolic, or degradative, reactions. On the other hand, the energy-requiring reactions are mostly involved in anabolism, the building of complex organic molecules from simpler ones. These reactions are called anabolic or biosynthetic reactions (Neidhardt Holde, 1990). Anabolic processes often involve dehydration synthesis reactions (reactions that release water) and require energy to form a new chemical bonds. Examples of anabolic processes are the formation of proteins from amino acids, nucleic acids from nucleotides, and polysaccharides from simple sugars. These biosynthetic reactions generate the materials for cell growth. Catabolic reactions are generally hydrolytic reactions (reactions that use water to break chemical bonds). Chemical bonds store energy; when they are broken, chemical energy is released. An example of catabolism occurs when cells break down sugars into carbon dioxide and water. Catabolic reactions furnish the energy needed to drive anabolic reactions. This coupling of energy-requiring and energy-releasing reactions is made possible through the molecule adenosime triphospahte (ATP). ATP stores energy derived from catabolic reactions and releases it later to drive anabolic reactions and perform other cellular work. A molecule of ATP consists of an adenine, a ribose, and three phosphate groups. When the terminal phosphate group is split from ATP, adenosine diphosphate (ADP) is formed, and energy is released to drive anabolic reactions. Using P to represent a phosphate group, we can write this reaction as (ATP— ADP + P + energy). Then, the energy from catabolic reactions is used to combine ADP and a P to resynthesize ATP (ADP + P + energy— ATP). Thus, anabolic reactions are coupled to ATP breakdown, and catabolic reactions are coupled to ATP synthesis. This concept of coupled reactions is very important. For now, you should know that the chemical composition of a living cell is constantly changing; some molecules are being broken down while others are being synthesized. This balanced flow of chemicals and energy maintains the life of a cell (â€Å"Metabolism; What is it exactly and how fast or slow should it be?†). B. Enzymes Chemical reactions occur when chemical bonds are formed or broken. In order for reactions to take place, atoms, ions, or molecules must collide. Whether a collision produces a reaction depends on the speed of the particles, the amount of energy required to trigger the reaction (called activation energy), and the specific configuration of the particles. The physiological temperature and pressure of organisms are too low for chemical reactions to occur quickly enough to maintain the life of the organism. Raising the temperature and pressure and the number of reacting molecules can increase the frequency of collisions and the rate of chemical reactions. However, such changes could damage or kill the organism. The living cell’s solution to this problem is a class of proteins called enzymes. Enzymes can speed up chemical reactions in several ways. For example, an enzyme may bring two reactant molecules close together and may properly orient them to react. Whatever the method, the result is that the enzyme lowers the activation energy for the reaction without increasing the temperature or pressure inside the cell (â€Å"Immobilized Enzymes Can Check Bioterrorism, 2003). Substances that can speed up a chemical reaction without themselves being altered are called catalysts. In living cells, enzymes serve as biological catalysts. As catalysts, enzymes are specific. Each acts on specific substance, called the enzyme’s substrate (or substrates when there are two or more reactants), and each catalyzes only one reaction. For example, sucrose (table sugar) is the substrate of the enzyme sucrase, which catalyzes the hydrolysis of sucrose to glucose and fructose. The specificity of enzymes is made possible by their structures. Enzymes are generally globular proteins that range in molecular weight from about 10,000 to several million. Each of the thousands of known enzymes has a characteristics three-dimensional shape with a specific surface configuration as a result of its primary, secondary, and tertiary structures. The unique configuration of each enzyme enables it to â€Å"find† the correct substrate from among the large number of diverse molecules in the cell (â€Å"Immobilized Enzymes Can Check Bioterrorism, 2003). C. Factors Influencing Enzymatic Activity Several factors influence the activity of enzyme. Among the more important are temperature, pH, substrate concentration, and inhibitors.   a.) Temperature The rate of most chemical reactions increases as the temperature increases. Molecules move more slowly at low than at higher temperatures and may not have enough energy to cause a chemical reaction. For enzymatic reactions, however, elevation beyond a certain temperature drastically reduces the rate of reaction. This decrease is due to the enzyme’s denaturation, the loss of its characteristics three-dimensional structure (tertiary configuration). Denaturation of a protein involves breakage of hydrogen bonds and other noncovalent bonds (Neidhardt Holde, 1990). b.) pH Most enzymes have a pH optimum at which their activity is characteristically maximal. Above or below this pH value, enzyme activity, and therefore the reaction rate, declines. When the H+ concentration (pH) in the medium is changed, many of the enzyme’s amino acids are affected and the protein’s three-dimensional structure is altered. Extreme changes in pH can cause denaturation (Neidhardt Holde, 1990). c.) Substrate Concentration There is a maximum rate at which a certain amount of enzymes can catalyze a specific reaction. Only when the concentration of substrate(s) is extremely high can this maximum rate be attained. Under conditions of high substrate concentration, the enzyme is said to be saturated; that is, its active site is always occupied by substrate or product molecules. In this condition, a further increase in substrate concentration will not affect the reaction rate because all active sites are already in used. If a substrate’s concentration exceeds a cell’s saturation level for a particular enzyme, the rate of reaction can be increased only if the cell produces additional enzyme molecules (Neidhardt Holde, 1990). However, under normal cellular conditions, enzymes are not saturated with substrate (s). At any given time, many of the enzyme molecules are inactive for lack of substrate; thus, the rate of reaction is likely to be influenced by the substrate concentration. d.) Inhibitors An effective way to control the growth of bacteria is to control their enzymes. Certain poisons, such as cyanide, arsenic, and mercury, combine with enzymes and prevent them from functioning. As a result, the cells stop functioning and die. Enzyme inhibitors are classified according to their mechanism of action as competitive inhibitors and noncompetitive inhibitors. Competitive inhibitors fill the active site of an enzyme and compete with the normal substrate for the active site. The competitive inhibitor is able to do this because its shape and chemical structure are similar to those of the normal substrate. Noncompetitive inhibitors do not compete with the substrate for the enzyme’s active site; instead they interact with another part of the enzyme. In this process, called allosteric (â€Å"other space†) inhibition, an enzyme’s activity is reduced because of a change in shape caused by binding of an inhibitor at a site rather than substrate’s binding site. The change in shape can be either reversible or irreversible (Neidhardt Holde, 1990). III. Conclusion In conclusion, the sum of all chemical within a living organism is known as metabolism. Catabolism refers to chemical reactions that result in the breakdown of more complex organic molecules into simpler substances. Catabolic reactions usually release energy. Anabolism refers to chemical reactions in which simpler substances are combined to form more complex molecules. Anabolic reactions usually require energy. The energy of catabolic reaction is used to drive anabolic reactions. The energy for chemical reactions is stores in ATP. Moreover, the enzymes are proteins produced by living cells that catalyze chemical reactions. They are generally globular proteins with characteristic three-dimensional shapes. Reference: Neidhardt, F.C. and K.E. van Holde. Biochemistry. Redwood City, Calif: Benjamin/Cummings, 1990. A biochemistry test with chapters on metabolic pathways of energy production and biosynthesis. â€Å"Metabolism; What Is It Exactly and How Fast or Slow Should It Be?† The Washington Times, January 31, 2006. â€Å"Immobilized Enzymes Can Check Bioterrorism.† USA Today (Society for the Advancement of Education), Vol. 131, June 2003 How to cite Metabolism, Essay examples Metabolism Free Essays Now that you are familiar with the structure of prokaryotic cells, we can discuss the activities that allow these microbes to thrive. The life support activity of even the most structurally simple organism involves a large number of complex biochemical reactions. Most, although not all, of the biochemical processes of bacteria also occur in eukaryotic microbes and in the cells of multicellular organisms, including humans. We will write a custom essay sample on Metabolism or any similar topic only for you Order Now However, the reactions that are unique to bacteria are fascinating because they allow microorganisms to do things we cannot do (Neidhardt Holde, 1990). For example, some bacteria (the chemoautotrophs) can grow on diets of such inorganic substances as carbon dioxide, iron, sulfur, hydrogen gas, and ammonia. This paper examines some representative chemical reactions that either produce energy (the catabolic reactions) or use energy (the anabolic reactions) in microorganisms. We will also look at how these various reactions are integrated within the cell. II. Discussion A. Catabolic and Anabolic Reactions We use the term metabolism to refer to the sum of all chemical reactions within a living organism. Because chemical reactions either release or require energy, metabolism can be viewed as an energy-balancing act. Accordingly, metabolism can be divided into two classes of chemical reactions—those that release energy and those that require energy. In living cells, the chemical reactions that release energy are generally the ones involved in catabolism, the breakdown of complex organic compounds into simpler ones. These reactions are called catabolic, or degradative, reactions. On the other hand, the energy-requiring reactions are mostly involved in anabolism, the building of complex organic molecules from simpler ones. These reactions are called anabolic or biosynthetic reactions (Neidhardt Holde, 1990). Anabolic processes often involve dehydration synthesis reactions (reactions that release water) and require energy to form a new chemical bonds. Examples of anabolic processes are the formation of proteins from amino acids, nucleic acids from nucleotides, and polysaccharides from simple sugars. These biosynthetic reactions generate the materials for cell growth. Catabolic reactions are generally hydrolytic reactions (reactions that use water to break chemical bonds). Chemical bonds store energy; when they are broken, chemical energy is released. An example of catabolism occurs when cells break down sugars into carbon dioxide and water. Catabolic reactions furnish the energy needed to drive anabolic reactions. This coupling of energy-requiring and energy-releasing reactions is made possible through the molecule adenosime triphospahte (ATP). ATP stores energy derived from catabolic reactions and releases it later to drive anabolic reactions and perform other cellular work. A molecule of ATP consists of an adenine, a ribose, and three phosphate groups. When the terminal phosphate group is split from ATP, adenosine diphosphate (ADP) is formed, and energy is released to drive anabolic reactions. Using P to represent a phosphate group, we can write this reaction as (ATP— ADP + P + energy). Then, the energy from catabolic reactions is used to combine ADP and a P to resynthesize ATP (ADP + P + energy— ATP). Thus, anabolic reactions are coupled to ATP breakdown, and catabolic reactions are coupled to ATP synthesis. This concept of coupled reactions is very important. For now, you should know that the chemical composition of a living cell is constantly changing; some molecules are being broken down while others are being synthesized. This balanced flow of chemicals and energy maintains the life of a cell (â€Å"Metabolism; What is it exactly and how fast or slow should it be?†). B. Enzymes Chemical reactions occur when chemical bonds are formed or broken. In order for reactions to take place, atoms, ions, or molecules must collide. Whether a collision produces a reaction depends on the speed of the particles, the amount of energy required to trigger the reaction (called activation energy), and the specific configuration of the particles. The physiological temperature and pressure of organisms are too low for chemical reactions to occur quickly enough to maintain the life of the organism. Raising the temperature and pressure and the number of reacting molecules can increase the frequency of collisions and the rate of chemical reactions. However, such changes could damage or kill the organism. The living cell’s solution to this problem is a class of proteins called enzymes. Enzymes can speed up chemical reactions in several ways. For example, an enzyme may bring two reactant molecules close together and may properly orient them to react. Whatever the method, the result is that the enzyme lowers the activation energy for the reaction without increasing the temperature or pressure inside the cell (â€Å"Immobilized Enzymes Can Check Bioterrorism, 2003). Substances that can speed up a chemical reaction without themselves being altered are called catalysts. In living cells, enzymes serve as biological catalysts. As catalysts, enzymes are specific. Each acts on specific substance, called the enzyme’s substrate (or substrates when there are two or more reactants), and each catalyzes only one reaction. For example, sucrose (table sugar) is the substrate of the enzyme sucrase, which catalyzes the hydrolysis of sucrose to glucose and fructose. The specificity of enzymes is made possible by their structures. Enzymes are generally globular proteins that range in molecular weight from about 10,000 to several million. Each of the thousands of known enzymes has a characteristics three-dimensional shape with a specific surface configuration as a result of its primary, secondary, and tertiary structures. The unique configuration of each enzyme enables it to â€Å"find† the correct substrate from among the large number of diverse molecules in the cell (â€Å"Immobilized Enzymes Can Check Bioterrorism, 2003). C. Factors Influencing Enzymatic Activity Several factors influence the activity of enzyme. Among the more important are temperature, pH, substrate concentration, and inhibitors. a.) Temperature The rate of most chemical reactions increases as the temperature increases. Molecules move more slowly at low than at higher temperatures and may not have enough energy to cause a chemical reaction. For enzymatic reactions, however, elevation beyond a certain temperature drastically reduces the rate of reaction. This decrease is due to the enzyme’s denaturation, the loss of its characteristics three-dimensional structure (tertiary configuration). Denaturation of a protein involves breakage of hydrogen bonds and other noncovalent bonds (Neidhardt Holde, 1990). Most enzymes have a pH optimum at which their activity is characteristically maximal. Above or below this pH value, enzyme activity, and therefore the reaction rate, declines. When the H+ concentration (pH) in the medium is changed, many of the enzyme’s amino acids are affected and the protein’s three-dimensional structure is altered. Extreme changes in pH can cause denaturation (Neidhardt Holde, 1990). Substrate Concentration There is a maximum rate at which a certain amount of enzymes can catalyze a specific reaction. Only when the concentration of substrate(s) is extremely high can this maximum rate be attained. Under conditions of high substrate concentration, the enzyme is said to be saturated; that is, its active site is always occupied by substrate or product molecules. In this condition, a further increase in substrate concentration will not affect the reaction rate because all active sites are already in used. If a substrate’s concentration exceeds a cell’s saturation level for a particular enzyme, the rate of reaction can be increased only if the cell produces additional enzyme molecules (Neidhardt Holde, 1990). However, under normal cellular conditions, enzymes are not saturated with substrate (s). At any given time, many of the enzyme molecules are inactive for lack of substrate; thus, the rate of reaction is likely to be influenced by the substrate concentration. Inhibitors An effective way to control the growth of bacteria is to control their enzymes. Certain poisons, such as cyanide, arsenic, and mercury, combine with enzymes and prevent them from functioning. As a result, the cells stop functioning and die. Enzyme inhibitors are classified according to their mechanism of action as competitive inhibitors and noncompetitive inhibitors. Competitive inhibitors fill the active site of an enzyme and compete with the normal substrate for the active site. The competitive inhibitor is able to do this because its shape and chemical structure are similar to those of the normal substrate. Noncompetitive inhibitors do not compete with the substrate for the enzyme’s active site; instead they interact with another part of the enzyme. In this process, called allosteric (â€Å"other space†) inhibition, an enzyme’s activity is reduced because of a change in shape caused by binding of an inhibitor at a site rather than substrate’s binding site. The change in shape can be either reversible or irreversible (Neidhardt Holde, 1990). III. Conclusion In conclusion, the sum of all chemical within a living organism is known as metabolism. Catabolism refers to chemical reactions that result in the breakdown of more complex organic molecules into simpler substances. Catabolic reactions usually release energy. Anabolism refers to chemical reactions in which simpler substances are combined to form more complex molecules. Anabolic reactions usually require energy. The energy of catabolic reaction is used to drive anabolic reactions. The energy for chemical reactions is stores in ATP. Moreover, the enzymes are proteins produced by living cells that catalyze chemical reactions. They are generally globular proteins with characteristic three-dimensional shapes. Reference: Neidhardt, F.C. and K.E. van Holde. Biochemistry. Redwood City, Calif: Benjamin/Cummings, 1990. A biochemistry test with chapters on metabolic pathways of energy production and biosynthesis. â€Å"Metabolism; What Is It Exactly and How Fast or Slow Should It Be?† The Washington Times, January 31, 2006. â€Å"Immobilized Enzymes Can Check Bioterrorism.† USA Today (Society for the Advancement of Education), Vol. 131, June 2003 How to cite Metabolism, Essay examples

Animal Farm Essay Prompts Example For Students

Animal Farm Essay Prompts The story takes place on a farm somewhere in England. The action of this novel starts when the oldest pig on the farm, Old Major, calls all animals to a secret meeting. He tells them about his dream of a revolution against the Mr. Jones. Three days later Major dies, but the speech gives the more intelligent animals a new outlook on life. The pigs, which are considered the most intelligent animals, instruct the other ones. During the period of preparation two pigs can distinguish themselves, Napoleon and Snowball. Napoleon is big, and although he isnt a good speaker, he can assert himself. Snowball is a better speaker, he has a lot of ideas and he is very vivid. Together with another pig called Squealer, who is a very good speaker, they work out the theory of Animalism. The rebellion start some months later, when Mr. Jones comes home drunk one night, and forgets to feed the animals. They break out of the barns and run to the house, where the food is stored. When Mr. Jones recognizes this he takes out his shotgun, but it is to late for him, all the animals fall over him and drive him off the farm. The animals destroy all whips nose rings, reins, and all other instruments that have been used to suppress them. The same day the animals celebrate their victory with an extra ration of food. The pigs made up the seven commandments, and they write them above the door of the big barn. 1. Whatever goes upon two legs is an enemy. 2. Whatever goes upon four legs, or has wings is a friend. 3. No animal shall wear clothes. 4. No animal shall sleep in a bed. 5. No animal shall drink alcohol. 6. No animal shall kill another animal. 7. All animals are equal. The animals also agree that no animal shall ever enter the farmhouse, and that no animal shall have contact with humans. These commandments are summarized in the simple phrase: Four legs well, two legs bad. After some time Jones comes back with some other men from the village to recapture the farm. The animals fight brave, and they manage to defend the farm. Snowball and Boxer receive medals of honor for defending the farm so bravely. Also Napoleon who had not fought at all takes a medal. This is the reason why the two pigs, Snowball and Napoleon, often argue. When Snowball presents his idea to build a windmill, to produce electricity to the other animals, Napoleon calls nine strong dogs. The dogs drive Snowball from the farm, and Napoleon explains that Snowball was in fact working with Mr. Jones. He also explains that Snowball in reality never had a medal of honor, that Snowball was always trying to cover up that he was fighting at the side of Mr. Jones. The animals then start building the windmill, and as time passes on the working-time goes up, whereas the food ration reduces. Although the common animals dont have enough food, the pigs grow fatter and fatter. They tell the other animals that they need more food, for they are managing the whole farm. Some time later the pigs explain to the other animals that they have to trade with the neighbor farms. The common animals are very upset, because after the revolution, there has been a resolution that no animal shall make trade with a human. But the pigs ensured that there never has been such a resolution, and that this was a bad lie of Snowball. Short after this decision the pigs move to the farmhouse. .u79c864865e8911f6938587dde5cf1e6a , .u79c864865e8911f6938587dde5cf1e6a .postImageUrl , .u79c864865e8911f6938587dde5cf1e6a .centered-text-area { min-height: 80px; position: relative; } .u79c864865e8911f6938587dde5cf1e6a , .u79c864865e8911f6938587dde5cf1e6a:hover , .u79c864865e8911f6938587dde5cf1e6a:visited , .u79c864865e8911f6938587dde5cf1e6a:active { border:0!important; } .u79c864865e8911f6938587dde5cf1e6a .clearfix:after { content: ""; display: table; clear: both; } .u79c864865e8911f6938587dde5cf1e6a { 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; } .u79c864865e8911f6938587dde5cf1e6a:active , .u79c864865e8911f6938587dde5cf1e6a:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u79c864865e8911f6938587dde5cf1e6a .centered-text-area { width: 100%; position: relative ; } .u79c864865e8911f6938587dde5cf1e6a .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u79c864865e8911f6938587dde5cf1e6a .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u79c864865e8911f6938587dde5cf1e6a .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; } .u79c864865e8911f6938587dde5cf1e6a:hover .ctaButton { background-color: #34495E!important; } .u79c864865e8911f6938587dde5cf1e6a .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u79c864865e8911f6938587dde5cf1e6a .u79c864865e8911f6938587dde5cf1e6a-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u79c864865e8911f6938587dde5cf1e6a:after { content: ""; display: block; clear: both; } READ: Economic Indicators Essay The other animals remember that there has been a commandment that forbids sleeping in beds, and so they went to the big barn to look at the commandments. When they arrive there they cant believe their eyes, the 4th commandment has been changed to, No animal shall sleep in bed with sheets. And the other commandments were also changed, No animal shall kill another animal without reason, or No animal shall drink alcohol in excess. Some months there is a heavy storm, which destroys the windmill that is nearly finished. Napoleon accuses Snowball of destroying the