The Giver Chapter four

Chapter 7 Study Guide Answers What does the Bill of Rights do? The Bill of Rights lists our basic rights. Who is the person mainly responsible for the Bill of Rights? James Madison is the person mainly responsible for the Bill of Rights. The Bill of Rights is part of which document? The Bill of Rights is part of the United States Constitution. Whose job is it to protect our rights listed in the bill of rights? It is the job of the federal courts (judicial branch) to protect our rights. What are the five rights listed in the first amendment? Freedom of speech: includes symbolic speech; does not include speech that could endanger the public safety. Religion: Right to believe whatever you want, but you can’t do whatever you want in the name of religion (can’t break the law). Press: The free flow of information and ideas; can’t print lies or information that could be helpful to an enemy in wartime. Assembly: Use public property for meetings and demonstrations (i.e. parades, protests, political rallies). Must be done legally and peaceably. Right to petition: Means you can appeal to the government if you’re unhappy about something or some policy. Give one example of speech NOT protected under the first amendment. An example of speech not protected under the first amendment would be crying “fire” in a crowded movie theater (anything that could potentially endanger the public safety). What does the second amendment give us the right to? The second amendment gives us the right to bear arms. What does the third amendment state we are not legally obligated to do? Under the third amendment, we are not obligated to quarter (or house) soldiers in our homes. What does the fourth amendment protect us from? The fourth amendment protects us from unreasonable search and seizure. What is needed in order to search or seize property? A warrant is needed, which must be issued by a judge, in order to search and seize property. What five rights are we guaranteed under the Fifth Amendment? Right to a grand jury: determines whether or not the government has enough evidence to bring someone to trial. Double jeopardy: Once a person has been found not guilty, he cannot be tried again for the same crime. Self incrimination: A person has the right to remain silent; he does not have to testify against himself. Due process: The government must follow a clear set of rules (a process) as it carries out the law and takes your life, liberty, or property. Just compensation: If the government has to take someone’s land, they will offer a fair price. What is the right stated in the “Miranda Warning”? The main right stated in the “Miranda Warning” is the right to remain silent. What are the four rights stated under the sixth amendment? Right to a speedy and public trial, and an impartial jury. Right to a jury of people that live in the defendant’s area (jury of your peers). To hear and question all witnesses Right to an attorney As stated in the seventh amendment, we have the right to which type of trial depending on how much money a person is being sued for? What can a judge NOT do? Under the seventh amendment, we have the right to a jury trial depending on how much money is at stake in a civil trial. A judge cannot overturn a decision made by a jury. What are the four things that are prohibited under the eighth amendment? The four things that are prohibited (or not allowed) under the eighth amendment are: excessive fines, excessive bail, cruel and unusual punishments, and poor prison conditions. Under the ninth amendment, rights not listed in the Bill of Rights belong to whom? According to the ninth amendment, rights not listed in the Bill of Rights belong to the people. The tenth amendment states that powers not given to the national government are reserved for whom? According to the tenth amendment, powers not specifically given to the national government are reserved for the people and the states. What is meant by the term “double jeopardy”? The term “double Jeopardy” refers to a person being retried for a crime in which he has already been acquitted, or found “not guilty”. What does it mean to be indicted by a grand jury? To be indicted by a grand jury means that a person will be going to trial and will retain all of the rights listed in the fifth, sixth, seventh, and eighth amendments.

Chapter One: Management Today The challenges of working in the new economy recognize: 1.1 Working Today Talent Talented people- What they know, what they learn and what they can achive The source of organisational performance Develop skills and improve What is intellectual capital The combined brain power and shared knowledge of an organization's employees TO orginzations: Intellectual capital resents a strategic asset as human creativity, insight and decision making can be converted into superior performance To individuals: Intellectual capital is a personal asset, one to be nurtured and continually updated Things evolve, make sure we keep updated Intellectual capital: The package on intellect skills and capabilities that set us apart making us valable to potential employers Maintaining your talent: There is no escaping the fact that your career success will require a lot of initiative, self awareness and continuous learning Technology Tech is in our everyday lives Latest developments Smart phone, smart apparel, smart cars, smart homes We struggle to keep up with social media ana staying connected with messaging, full of email and voicemail What happenings as younger workers advance into management Flexibility Work ethic It is critical to build and maintain a high Tech IQ! What is Tech IQ: The ability to use current technologies at work and in your personal life, combined with the commitment to keep yourself updated as technology continues to evolve Intellectual capi5la is a combination of: Commitment x Competency = Intellectual capital How to make the world a better place Globalisation The worldwide interdependence of resources flows, product markets and business competition Under the influence, government leaders worry and about the competitiveness of nations just as corporate leaders worry about business competitiveness Emerging markets will power global growth over the next 20 years. By 2025 overall global consumption is forecast to reach $62 trillion, twice its 2013 level and fully half of this increase will come from the emerging world Consequence: Going to fast in uses resources, inflation, corporate greed It's cheaper to have things made in different countries (wages are low and going down) Shamrock organization 1 leaf - full time employees- standard career paths 2 leaf - “freelancers” 3 leaf - Part times without benefits (first to lose their jobs when employers face economic difficulties) The rising of emerging markets Now account for 60% of all low and medium technology manufacturing worldwide Total value add in high tech manufacturing from a low 26% in the 1970s to 48% at present China strategy to upgrade its industries and move the manufacturing value ching by prioritising 10 sectors Information technology, robotic, aerospace, maritime equipment, modern railway equipment, alternative energy vehicles, power equipment, agriculture equipment, advanced materials, biopharma and medical products Ethics A code of moral principa;s that sets standards for conduct that is “good” and “right” as well as “bad” and “wrong” Enron company huge corruption even in elections same thing happened with The Mechanism 1.2 - Organizations Organizational Purpose An orgnizations is a collection of people working together to achieve a common purpose Unique social phenomenon that enables its members to perform tasks far beyond the reach of individual accomplishment (synergy) The broad purpose of any orginzation is to provide goods or services of value to customers and clients A clear sense of purpose tied to: Quality of products and services Customer satisfaction Social responsibility Can be an important source of organisational strength and performance advantage All organisations are open systems (Systems that interact with its environment for renewal and growth) Organizations as systems All organizations are open systems that interact with their environment Continual process of obtaining resource inputs-people, information, resources and capital- and transforming them into outputs in the form of finished goods and services for customers One simple way to assess the impact of any organisation is to ask the question: How is the world different because it existed Value Creation: Organisations create value when they use resources well to produce good products and take care of their customers One simple way to assess the impact of any organization is to ask the questions: How is the world different because it existed? The 3 Ps of organizational performance Profit - is the decision economically sound? People - Does the decision treat people with respect and dignity? Planet - Is the decision good for the environment? Productivity: An overall measure of the quantity and quality of work performance with recourse utilisation taken into account Performance effectiveness: An output measure of task or goal accomplishment Performance efficiency: An input measure of the resource costs associated with goal accomplishment. Workplace changes that impact management Focus on valuing human capital Demise of “Command and control” Emphasis on teamwork Pre-eminence of technology New workforce expectations Importance of networking Concern for sustainability 1.3 Managers Importance of human resources and manger People are not ‘costs to be controlled’ High performing organizations treat people as valuable strategic assets Three takeaways 1. Give leaders broad authority 2. Encourage them to think like CEO 3. Challenge strong performers ealy with big opportunities Direct support, supervise and help activate the work efforts of others The people who managers help are the ones whose contributions represent the real work of the organisation Types of managers Line managers are responsible for work activities that directly affect organization’s output Staff managers use technical expertise to advise and support the efforts of line workers Functional managers are responsible for a single area of activity Quality of work life (QWL) An indicator of the overall quality of human experiences in the workplace QWL Indicators Respect Fair pay Safe working conditions Opportunities to learn and use new skills Room to grow and progress in a career Protection of individuals rights The organization as an upside-down pyramid A manager’s job is to support worker’s efforts The best managers are known for helping and supporting Customers at the top served by worker who are supported by managers 1.4 The management Process Managers achieve high performance for their organizations by best utilizing its humans and material resources Management is the process of planning, organizing, leading and controlling the use of resources to accomplish performance goals All managers are responsible for the four functions The functions are carried on continually Characteristics of managerial work Long hours Intense pace Fragmented and varied tasks Many communication media Filled with interpersonal relationships Managerial agendas and networks Agenda setting Develops action priorities for accomplishing goals and plans Networking Process of building and maintaining positive relationships with people who can help advance agendas Social Capital Capacity to attract support and help from others Learning The change in a behaviour that results from experience Lifelong learning The process of continuously learning from daily experiences and opportunities

Chapter 7 - Review Data and Decision Making *Glow bus due at midnight, name and student number: answer questions using content in class People have created wonderful things for centuries, and management Management can be traced as far back as 500 bc when the ancient Sumerians used written records to improve government and business activities Why is it important to lean from the past Not to repeat our mistakes Classical management approaches Scientific management Administrative Principles Bureaucratic organisation Behavioural Management Approaches Follett’s Organizations as communities The Hawthorne studies Maslow’s theory of human needs Mcgregor’s Theory x and Theory Y Argyris Personality and organisation Modern Management foundations Organises as systems Contingency thinking Quality management Quantitative and analysis and tools Evidence-based management Contributions Frederick Taylor - Father of Scientific management He noticed that workers often did their jobs with wasted motions and without a constant approach. His resulted in inefficiency and low performance He believed the problem could be fixed if workers were taught to do their jobs in the best ways and ten were helped and guided by supervisors Four guiding principles of scientific management Rules of motion, standardized work and proper working conditions Select workers with the right abilities Train workers and give them incentives Support workers by planning and smoothing the way as they do their work Frank and Lillian Gilbreth Pioneered use of motitono studies as a management tool In one famous case, the gilbreaths cut down the number of motions used by bricklayers adn tripled their productivity Contributions from scientific management Make results-based compensation a performance incentive Carefully design jobs with efficient work methods Carefully select workers with the ability to perform the job Trian workers to execute activities to the best of their abilities Train supervisors to support workers so they can perform jobs to the best of their abilities Classical Management Adiminstative principle (Henro Fayol) 1919, after a career in French industry, Henri F published “adminisration Industrielle et Generale” (General and industrial management) in which we out like his views on the management of organiztion and workers Rules and duties in management Foresight - to complete a plan of action for the future Organization - To provide and mobilize resources to implement the plan Common- to lead, select and evaluate workers to get the best work toward the plan Coordination- to fit diverse efforts together and ensure information is shared and problems solved Control- to make sure things happen according to plan and to take necessary corrective action Classical management Bureacratic organiztion (Max Weber) Max weber (Bureaucrativ organization) - late 19th century German political economist who had a major impact in the fields of management and sociology Bureaucratic Organization An ideal, intentionally rational adn very efficient form of organization Based on the principles of logic, order and legitimate authority Characteristics of BO Clear division of labour Clear hierarchy of authority Formal rules and procedure Impersonality Careers based on merit What are some disadvantages of bureaucracy Takes a long time for problems to become solved bec there are procedures and there is a chain of people in command Having the power Rules have to follow Excessive paperwork or “red tape” Slowness in handling problems Rigidity in the face of shifting needs Resistance to change Employee apathy Behavioural Management Approaches (focus on understanding the elements that affect human behaviour in organisations) Follett’s Organizations as communites Mary park follett contributed to the transition from classical thinking inot behavioural management Groups and human cooperation Groups allow individuales too combine their talents for a greater good Organizations are cooperating “communites” of managers adn workers Managers job is to help people copperate and achive an integration of goals and intrests Forward-looking managment insight: Making every emploee an owner creates a sense of collective responsibility Prescursor of employrr ownership, profit sharing and gain sharing Buniess problems invovle a varity of inter realted factors Prescursor of systems thinking Private profits realtive to public good Precursor of managerial ethics and social respinsibility Hawthorne studies Took place at western electric chicago plan, a tran led by Harvards Elton Mayo set out to learn how econmic incentives and workplace conditions affected workers output Maing objective Intial study examined how ecomoin incentives adn physical conditions affected worker output (productivity) No consistent relationship found During experientmetn they had 2 groups The expertiant groups (impoved wokring ocnditions ) The control group ( no changes to original working conidtions) No consitant relationship found, perfomance in both groups increased even after removing incentives Social setting and human relations Concluded New “social setting” led workers to do good job Good “Human relations” = higher productivity The contect - The Great Depression (1929-1940) Employee attitudes and groups processes Osme thinsf satisifed some workers but not others People resticited output to adhere to groups norms (Avoid layoffs) Lessons from he hawthrone stufirs Social and human concerns are keys to prductivity Hawthrone effect - People who are singled out for special attention perform as expected Maslow’s Theory of human needs Human needs The work of psychologist Abraham Maslow in the area if human “needs,” also has had a major impact in the behavioual apporach to management Maslow’s hierarchy of human needs Self actualization needs Higherst level: need foe self fulfillment to grow and use abilites to fullest and most creative extent Esteem needs Needs fro esteem in eyes of others need for respect, prestige, recognition; need for self esteem, personal sense of competence, mastery Social needs Need for love, affection, sense of belongingness in ones relationship either other people Safett needs Need for security, protection and stability in teh events of day to day life Physiological needs Most basic of all human needs: need for biological maintence; food, water and phydical well being Principles Defict principle: A satidifed need is not a motivator of behaviour Progress principles: A need becomes a motivator once the preceding lower-level need is satisfied Both principles cease to operate at self actulilzation level McGregor’s Theories Thepry x assumes that workers; Dislike work Lack ambition Are irresponsible Resist change Prefer to be led Theoyry y assumes that workers are Willing to work Willing to accept responsibility Capable of self control Capable of self direction Imaginative and creative According to McGregor, Managers create: Self fulfilling prophecies Implications of Theory x and y Theory x managers: Create situations where workers become dependent, passive and reluctant Theory y managers create situations where workers respond with initiative and high performance Central to notions of empowerment and self management Argyris’s theory of adult personality Classical management principles and practices inhibit worker maturation and are inconsistent with the mature adult personality Management practices should accommodate the mature personality: Increasing task responsibility Increasing task variety Using participative decision making Modern Management Foundation Quantitative analysis and Tools Analytics: the use of large data bases and mathematics to solve problems and make informed decision using systematic analysis Organization as systems System Collection of interrelated parts that function together to achieve a common purpose Subsystem A smaller component of a larger system Open systems Organisations that interact with their environment Contingency thinking Tires to maths managerial responses with problem (situation) No “one best way” to manage The “appropriate way to to manage depends on the situations Quality management Qality anc competitive advantafe are linked Total quality managment (TQM) Comprehensive approach to contiou impovment on teh entire organization ISO certification Gloval quality management standards Refine and upgrade quality to meet ISO requirments Evidednce Based Managment Making management decision on “hard facts” about what really works

Commas Directions: Correct the sentences by adding commas where needed. 1. After the sound of the bell we realized it was a false alarm. 2. Mr. Yoshino the head of the department resigned yesterday. 3. The gentleman with the black umbrella who is an ambassador to the United States said hello to us as we were entering the hotel. 4. Even though we won the game the players unfortunately did not play their best. 5. Heather walked quickly up to the door and knocked hoping that someone would answer. Author’s Purpose 6. An author writes a story about a boy who saves his town from a flood by using his quick thinking. The author includes exciting descriptions of the boy's bravery. What is the author’s most likely purpose for writing this story? A. To inform readers about the dangers of floods B. To entertain readers with a heroic tale C. To explain how to prevent floods D. To persuade readers to prepare for emergencies 7. Which of the following is an example of an author writing to persuade? A. A science textbook chapter explaining the water cycle B. A commercial encouraging people to adopt shelter pets C. A short story about a girl who finds a magical necklace D. A recipe for making chocolate chip cookies 8. Read the following sentence: "Studies show that students who read for 20 minutes a day score higher on tests. Reading is one of the best habits you can develop for success in school and life." What is the author’s purpose in this passage? A. To entertain readers with a fun story B. To persuade readers to read more often C. To inform readers about how books are written D. To explain how to find books to read 9. An author writes a how-to guide titled 10 Easy Steps to Plant a Garden. What is the author’s primary purpose? A. To persuade readers to grow their own vegetables B. To inform readers how to plant a garden C. To entertain readers with funny garden tips 10. Read the excerpt: "Long ago, in a village surrounded by mountains, the people discovered a secret about their water well. Every full moon, the well water turned to gold for just one night. But no one knew why. This mystery brought travelers from far and wide, hoping to uncover the truth." What is the author’s purpose in this excerpt? A. To persuade readers to visit the village B. To inform readers about a historical event C. To entertain readers with a mysterious tale D. To explain the science behind the water Main Idea When I stepped out into the bright sunlight from the darkness of the movie house, I had only two things on my mind: Paul Newman and a ride home. I was wishing I looked like Paul Newman--- he looks tough and I don't--- but I guess my own looks aren't so bad. I have light-brown, almost-red hair and greenish-gray eyes. I wish they were more gray because I hate most guys that have green eyes, but I have to be content with what I have. My hair is longer than a lot of boys wear theirs, squared off in back and long at the front and sides, but I am a greaser and most of my neighborhood rarely bothers to get a haircut. Besides, I look better with long hair. 11. What is the main idea? The narrator likes movies. The narrator wishes he was Paul Newman. The narrator is content with his appearance. The narrator looks better with long hair. 12. The narrator believes. . . looks are important. he should get a haircut. green eyes are bad. that he has red hair. Once there were four girls who shared a pair of pants. The girls were all different sizes and shapes, and yet the pants fit each of them. You may think this is a suburban myth. But I know it's true, because I am one of them, one of the sisters of the Traveling Pants. We discovered their magic last summer, purely by accident. The four of us were splitting up for the first time in our lives. Carmen had gotten them from a secondhand place without even bothering to try them on. She was going to throw them away, but by chance, Tibby spotted them. First Tibby tried them; then me, Lena; then Bridget; then Carmen. By the time Carmen pulled them on, we knew something extraordinary was happening. If the same pants fit and I mean really fit the four of us, they aren't ordinary. They don't belong completely to the world of things you can see and touch. My sister, Effie, claims I don't believe in magic, and maybe I didn't then. But after the first summer of the Traveling Pants, I do. 13. What is the main idea? Four friends were connected through a special pair of pants. A pair of pants called the Traveling Pants. Carmen finding a pair of pants from a second-hand shop. The girls believing in magic. 14. The narrator included that the pants fit all of them to emphasize how the girls become friends. the girls are different sizes. why the pants are special. where the pants came from. If you are interested in stories with happy endings, you would be better off reading some other book. In this book, not only is there no happy ending, there is no happy beginning and very few happy things in the middle. This is because not very many happy things happened in the lives of the three Baudelaire youngsters. Violet, Klaus, and Sunny Baudelaire were intelligent children, and they were charming, and resourceful, and had pleasant facial features, but they were extremely unlucky, and most everything that happened to them was rife with misfortune, misery, and despair. I'm sorry to tell you this, but that is how the story goes. 15. What is the main idea? description about the story to come. A warning about the story and its sad content. A declaration about the Baudelaire family. A beginning for the end of the story. 16. The narrator believes the reader does not like sad stories. likes stories with happy endings. can’t enjoy the story. will find the story unhappy. 17. Read the following sentence: Of course you can exaggerate your story, but what you say must be based on truth. Which word means the same as exaggerate? repeat reveal overstate increase 18. What is the meaning of the word inaugurated, used in the following sentence: Less than two months after Abraham Lincoln was inaugurated President in 1861, he encountered one of the most difficult tasks ever experienced by a United States leader: civil war. elected by a vote brought into office identified by name viewed as an authority 19. What does the phrase “practice your presentation so much that you could do it in your sleep” suggest in the following sentence: The best advice is to practice your presentation so much that you could do it in your sleep. get plenty of sleep the night before giving a presentation give their presentations in front of a small audience first take advice from their teachers on how to write a presentation memorize their presentations before they give them 20. Read the following sentence: The Phoenix Mars Lander is a NASA spacecraft that landed on the Red Planet in May 2009 to study the history of water and potential for life on the planet. What is another word for potential? existence situation possibility qualification

CARBOHYDRATES Carbohydrates are organic compounds composed of carbon, hydrogen, and oxygen in a ratio of about one carbon atom to two hydrogen atoms to one oxygen atom. The number of carbon atoms in a carbohydrate varies. Some carbohydrates serve as a source of energy. Other carbohydrates are used as structural materials. Carbohydrates can exist as monosaccharides, disaccharides, or polysaccharides. Monosaccharides A monomer of a carbohydrate is called a monosaccharide (MAHN-oh-SAK-uh-RIED). A monosaccharide—or simple sugar— contains carbon, hydrogen, and oxygen in a ratio of 1:2:1. The gen- eral formula for a monosaccharide is written as (CH2O)n, where n is any whole number from 3 to 8. For example, a six-carbon mono- saccharide, (CH2O)6, would have the formula C6H12O6. The most common monosaccharides are glucose, fructose, and galactose, as shown in Figure 3-6. Glucose is a main source of energy for cells. Fructose is found in fruits and is the sweetest of the monosaccharides. Galactose is found in milk. Notice in Figure 3-6 that glucose, fructose, and galactose have the same molecular formula, C6H12O6, but differing structures. The different structures determine the slightly different properties of the three compounds. Compounds like these sugars, with a single chemical formula but different structural forms, are called isomers (IE-soh-muhrz). SECTION 2 OBJECTIVES ● Distinguish between monosaccharides, disaccharides, and polysaccharides. ● Explain the relationship between amino acids and protein structure. ● Describe the induced fit model of enzyme action. ● Compare the structure and function of each of the different types of lipids. ● Compare the nucleic acids DNA and RNA. VOCABULARY carbohydrate monosaccharide disaccharide polysaccharide protein amino acid peptide bond polypeptide enzyme substrate active site lipid fatty acid phospholipid wax steroid nucleic acid deoxyribonucleic acid (DNA) ribonucleic acid (RNA) nucleotide C HO H C H OH C OH H C CH2OH H C H OH O Glucose C OH C O H OH C OH H CH2OH C H CH2OH Fructose C H HO C OH H C OH H C CH2OH H C H OH O Galactose Glucose, fructose, and galactose have the same chemical formula, but their structural differences result in different properties among the three compounds. FIGURE 3-6 Copyright © by Holt, Rinehart and Winston. All rights reserved. 56 CHAPTER 3 Disaccharides and Polysaccharides In living things, two monosaccharides can combine in a condensa- tion reaction to form a double sugar, or disaccharide (die-SAK-e-RIED). For example in Figure 3-4, the monosaccharides fructose and glu- cose can combine to form the disaccharide sucrose. A polysaccharide is a complex molecule composed of three or more monosaccharides. Animals store glucose in the form of the polysaccharide glycogen. Glycogen consists of hundreds of glucose molecules strung together in a highly branched chain. Much of the glucose that comes from food is ultimately stored in your liver and muscles as glycogen and is ready to be used for quick energy. Plants store glucose molecules in the form of the polysaccha- ride starch. Starch molecules have two basic forms—highly branched chains that are similar to glycogen and long, coiled, unbranched chains. Plants also make a large polysaccharide called cellulose. Cellulose, which gives strength and rigidity to plant cells, makes up about 50 percent of wood. In a single cellu- lose molecule, thousands of glucose monomers are linked in long, straight chains. These chains tend to form hydrogen bonds with each other. The resulting structure is strong and can be broken down by hydrolysis only under certain conditions. PROTEINS Proteins are organic compounds composed mainly of carbon, hydrogen, oxygen, and nitrogen. Like most of the other biological macromolecules, proteins are formed from the linkage of monomers called amino acids. Hair and horns, as shown in Figure 3-7a, are made mostly of proteins, as are skin, muscles and many biological catalysts (enzymes). Amino Acids There are 20 different amino acids, and all share a basic structure. As Figure 3-7b shows, each amino acid contains a central carbon atom covalently bonded to four other atoms or functional groups. A single hydrogen atom, highlighted in blue in the illustration, bonds at one site. A carboxyl group, —COOH, highlighted in green, bonds at a second site. An amino group, —NH2, highlighted in yel- low, bonds at a third site. A side chain called the R group, high- lighted in red, bonds at the fourth site. The main difference among the different amino acids is in their R groups. The R group can be complex or it can be simple, such as the CH3 group shown in the amino acid alanine in Figure 3-7b. The differences among the amino acid R groups gives different proteins very different shapes. The different shapes allow pro- teins to carry out many different activities in living things. Amino acids are commonly shown in a simplified way such as balls, as shown in Figure 3-7c. (a) Many structures, such as hair and horns are made of proteins. (b) Proteins are made up of amino acids. Amino acids differ only in the type of R group (shown in red) they carry. Polar R groups can dissolve in water, but nonpolar R groups cannot. (c) Amino acids have complex structures, so, in this and other textbooks, they are often simplified into balls. FIGURE 3-7 (b) Alanine (an amino acid) (c) Simplified version of amino acid CH3 H N OH C C H O H (a) Copyright © by Holt, Rinehart and Winston. All rights reserved. BIOCHEMISTRY 57 H H N C C OH H O H CH3 H2O Glycine Alanine H N OH C C H O H H H N C C H O H CH3 N OH C C H O H (a) (b) (a) The peptide bond (shaded blue) that binds amino acids together to form a polypeptide results from a condensation reaction that produces water. (b) Poly- peptides are commonly shown as a string of balls in this textbook and elsewhere. Each ball represents an amino acid. FIGURE 3-8 Substrate Products Enzyme 1 2 3 In the induced fit model of enzyme action, the enzyme can attach only to a substrate (reactant) with a specific shape. The enzyme then changes and reduces the activation energy of the reaction so reactants can become products. The enzyme is unchanged and is available to be used again. 3 2 1 FIGURE 3-9 Dipeptides and Polypeptides Figure 3-8a shows how two amino acids bond to form a dipeptide (die-PEP-TIED). In this condensation reaction, the two amino acids form a covalent bond, called a peptide bond (shaded in blue in Figure 3-8a) and release a water molecule. Amino acids often form very long chains called polypeptides (PAHL-i-PEP-TIEDZ). Proteins are composed of one or more polypep- tides. Some proteins are very large molecules, containing hun- dreds of amino acids. Often, these long proteins are bent and folded upon themselves as a result of interactions—such as hydrogen bonding—between individual amino acids. Protein shape can also be influenced by conditions such as temperature and the type of solvent in which a protein is dissolved. For exam- ple, cooking an egg changes the shape of proteins in the egg white. The firm, opaque result is very different from the initial clear, runny material. Enzymes Enzymes—RNA or protein molecules that act as biological catalysts—are essential for the functioning of any cell. Many enzymes are proteins. Figure 3-9 shows an induced fit model of enzyme action. Enzyme reactions depend on a physical fit between the enzyme molecule and its specific substrate, the reactant being catalyzed. Notice that the enzyme has folds, or an active site, with a shape that allows the substrate to fit into the active site. An enzyme acts only on a specific substrate because only that substrate fits into its active site. The linkage of the enzyme and substrate causes a slight change in the enzyme’s shape. The change in the enzyme’s shape weakens some chemical bonds in the substrate, which is one way that enzymes reduce activation energy, the energy needed to start the reaction. After the reaction, the enzyme releases the products. Like any catalyst, the enzyme itself is unchanged, so it can be used many times. An enzyme may not work if its environment is changed. For example, change in temperature or pH can cause a change in the shape of the enzyme or the substrate. If such a change happens, the reaction that the enzyme would have catalyzed cannot occur.

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