1) The document discusses key concepts about metabolism from chapters 5.1-5.4 of a biology textbook, including how enzymes work to catalyze reactions and the roles of ATP, activation energy, and temperature and pH in metabolism.
2) It explains how alcohol is broken down by the liver enzyme alcohol dehydrogenase and how energy flows through biological systems in one direction according to the laws of thermodynamics.
3) The summary highlights that ATP couples exergonic and endergonic reactions to do cellular work and that enzymes lower activation energies to speed up metabolic reactions.
KEY CONCEPTS
8.1 An organism’s metabolism transforms matter and
energy, subject to the laws of thermodynamics
8.2 The free-energy change of a reaction tells us whether or not the reaction occurs
spontaneously
8.3 ATP powers cellular work by coupling exergonic reactions to endergonic reactions
8.4 Enzymes speed up metabolic reactions by lowering energy barriers
8.5 Regulation of enzyme activity helps control metabolism
1. Cells require a constant supply of energy to maintain their internal organization and carry out reactions through metabolism. Energy flows through ecosystems in a unidirectional manner as it is transformed and some is lost as heat.
2. ATP is the energy currency of cells that is regenerated through exergonic reactions and used to drive endergonic reactions. Metabolic pathways involve series of enzyme-catalyzed reactions that convert food into ATP.
3. Photosynthesis and cellular respiration are key redox reactions that allow the flow of energy from the sun through living things by cycling molecules between chloroplasts and mitochondria.
This document provides an overview of cellular respiration and metabolism. It defines key terms and outlines the metabolic pathways of aerobic and anaerobic respiration. Aerobic respiration uses oxygen to produce 36 ATP through glycolysis, the Krebs cycle, and oxidative phosphorylation. Anaerobic respiration produces 2 ATP through glycolysis and fermentation when oxygen is absent. Metabolism consists of both anabolic and catabolic processes, with anabolism requiring ATP to build molecules and catabolism releasing energy through ATP.
The document provides an overview of key concepts in metabolism. It defines the first and second laws of thermodynamics, and discusses how cells use ATP to do work through energy coupling. Enzymes lower the activation energy of reactions and work with specificity on substrates. Regulation allows cells to control metabolic pathways and switch enzyme activity on and off through mechanisms like feedback inhibition and allosteric regulation.
The document discusses key concepts related to cellular energy and metabolism. It covers forms of energy, the laws of thermodynamics, ATP as a carrier of chemical energy, metabolic pathways, enzymes, and the processes of photosynthesis and cellular respiration. ATP is constantly regenerated from ADP through coupled reactions, where exergonic reactions capture energy to drive endergonic reactions like cellular work functions. Enzymes lower the activation energy of reactions and catalyze metabolic pathways by binding substrates in their active sites.
This document discusses metabolism and energy transformations in living systems. It covers topics like thermodynamics, metabolic pathways, oxidation-reduction reactions, and experimental approaches to study metabolism. Key points include:
- ATP is used as the main "currency" of energy in cells and is generated by catabolic reactions and used by anabolic reactions.
- Electron transfer reactions and phosphorylation group transfers are two major mechanisms for energy transfer in biological systems.
- Metabolic pathways are organized series of chemical reactions that are regulated and sometimes compartmentalized within cells.
- Experimental techniques like isolating enzymes and studying genetic defects help uncover regulatory mechanisms and blocked steps in metabolism.
This document provides an overview of metabolism and oxidative phosphorylation. It defines oxidative phosphorylation as the formation of ATP using energy released by electron transfer through electron carriers in the mitochondrial inner membrane. A proton gradient couples ATP formation to electron transfer. Catabolic pathways break down molecules and release energy, while anabolic pathways use energy to build molecules. ATP powers cellular work by coupling exergonic reactions that release energy to endergonic reactions that require energy. Enzymes lower the activation energy of reactions and increase their rates.
Bioenergetics deals with energy changes in biochemical reactions, specifically the initial and final energy states without considering mechanisms. Energy rich compounds store energy that can be released, such as ATP which contains energy in its phosphate bonds and is used universally in metabolism. Cyclic AMP is synthesized from ATP by adenyl cyclase and acts as a second messenger in intracellular signal transduction such as regulating metabolism.
KEY CONCEPTS
8.1 An organism’s metabolism transforms matter and
energy, subject to the laws of thermodynamics
8.2 The free-energy change of a reaction tells us whether or not the reaction occurs
spontaneously
8.3 ATP powers cellular work by coupling exergonic reactions to endergonic reactions
8.4 Enzymes speed up metabolic reactions by lowering energy barriers
8.5 Regulation of enzyme activity helps control metabolism
1. Cells require a constant supply of energy to maintain their internal organization and carry out reactions through metabolism. Energy flows through ecosystems in a unidirectional manner as it is transformed and some is lost as heat.
2. ATP is the energy currency of cells that is regenerated through exergonic reactions and used to drive endergonic reactions. Metabolic pathways involve series of enzyme-catalyzed reactions that convert food into ATP.
3. Photosynthesis and cellular respiration are key redox reactions that allow the flow of energy from the sun through living things by cycling molecules between chloroplasts and mitochondria.
This document provides an overview of cellular respiration and metabolism. It defines key terms and outlines the metabolic pathways of aerobic and anaerobic respiration. Aerobic respiration uses oxygen to produce 36 ATP through glycolysis, the Krebs cycle, and oxidative phosphorylation. Anaerobic respiration produces 2 ATP through glycolysis and fermentation when oxygen is absent. Metabolism consists of both anabolic and catabolic processes, with anabolism requiring ATP to build molecules and catabolism releasing energy through ATP.
The document provides an overview of key concepts in metabolism. It defines the first and second laws of thermodynamics, and discusses how cells use ATP to do work through energy coupling. Enzymes lower the activation energy of reactions and work with specificity on substrates. Regulation allows cells to control metabolic pathways and switch enzyme activity on and off through mechanisms like feedback inhibition and allosteric regulation.
The document discusses key concepts related to cellular energy and metabolism. It covers forms of energy, the laws of thermodynamics, ATP as a carrier of chemical energy, metabolic pathways, enzymes, and the processes of photosynthesis and cellular respiration. ATP is constantly regenerated from ADP through coupled reactions, where exergonic reactions capture energy to drive endergonic reactions like cellular work functions. Enzymes lower the activation energy of reactions and catalyze metabolic pathways by binding substrates in their active sites.
This document discusses metabolism and energy transformations in living systems. It covers topics like thermodynamics, metabolic pathways, oxidation-reduction reactions, and experimental approaches to study metabolism. Key points include:
- ATP is used as the main "currency" of energy in cells and is generated by catabolic reactions and used by anabolic reactions.
- Electron transfer reactions and phosphorylation group transfers are two major mechanisms for energy transfer in biological systems.
- Metabolic pathways are organized series of chemical reactions that are regulated and sometimes compartmentalized within cells.
- Experimental techniques like isolating enzymes and studying genetic defects help uncover regulatory mechanisms and blocked steps in metabolism.
This document provides an overview of metabolism and oxidative phosphorylation. It defines oxidative phosphorylation as the formation of ATP using energy released by electron transfer through electron carriers in the mitochondrial inner membrane. A proton gradient couples ATP formation to electron transfer. Catabolic pathways break down molecules and release energy, while anabolic pathways use energy to build molecules. ATP powers cellular work by coupling exergonic reactions that release energy to endergonic reactions that require energy. Enzymes lower the activation energy of reactions and increase their rates.
Bioenergetics deals with energy changes in biochemical reactions, specifically the initial and final energy states without considering mechanisms. Energy rich compounds store energy that can be released, such as ATP which contains energy in its phosphate bonds and is used universally in metabolism. Cyclic AMP is synthesized from ATP by adenyl cyclase and acts as a second messenger in intracellular signal transduction such as regulating metabolism.
This document discusses bioenergetics and energy production through the TCA (Krebs) cycle. It defines bioenergetics as the part of biochemistry concerned with energy flow through living systems. It explains that living organisms obtain energy through breaking chemical bonds and oxidizing materials, often with oxygen. The energy is used to produce ATP, which acts as an energy battery. The TCA cycle is described as a series of chemical reactions that starts and ends with oxaloacetate, and produces 1 ATP, 3 NADH, and 1 FADH2 per turn to generate energy.
This document summarizes key concepts in bioenergetics and cellular respiration. It discusses how living organisms obtain and use energy through redox reactions and electron carriers like ATP. Photosynthesis and cellular respiration are introduced as the two main pathways of energy transformation. Photosynthesis uses energy from sunlight to synthesize glucose from carbon dioxide and water, while cellular respiration breaks down glucose to release energy through glycolysis, the Krebs cycle, and the electron transport chain. The document aims to explain the basic processes of how energy is transformed and utilized in living cells and organisms.
Organisms obtain energy through cellular processes like cellular respiration and photosynthesis. Cellular respiration breaks down food molecules to release energy, some as heat and some stored as ATP, which cells can use like money. Photosynthesis uses light energy from the sun to produce food molecules. Autotrophs like plants can produce their own food using photosynthesis, while heterotrophs must ingest food to get energy through cellular respiration.
The study of energy in living systems (environments) and the organisms (plants and animals) that utilize them.
I'm a st.Xavier's student . i think this ppt will be helpful to the others. Because this is needed in our daily life.
Bioenergetics is the study of energy transformations in living systems. Organisms need energy for physiological activities, which involve chemical reactions. Energy is utilized or generated in these reactions according to the laws of thermodynamics. Light provides energy for all organisms, as green plants capture light energy and convert it into chemical energy stored in glucose. Adenosine triphosphate (ATP) acts as the energy currency of cells, containing energy in its phosphate bonds. ATP transfers energy between energy-releasing and energy-consuming reactions through phosphorylation, the addition of phosphate groups. There are three types of phosphorylation: photophosphorylation using sunlight, and oxidative and substrate phosphorylation using energy from oxidation or substrate hydrolysis.
1) The document discusses light-dependent (photosynthetic) generators of proton potential, specifically focusing on the photosynthetic apparatus of purple bacteria.
2) Photosynthesis in purple bacteria involves a light-dependent cyclic redox chain where absorption of light by bacteriochlorophyll leads to electron transfer across the membrane, generating a proton gradient.
3) Key components of the redox chain include bacteriochlorophyll dimer and monomer, bacteriopheophytin, ubiquinone, cytochromes, and a nonheme iron-sulfur protein that facilitate electron transfer and proton pumping across the membrane.
The document summarizes key topics in biochemistry including metabolism, bioenergetics, and biochemical pathways. Specifically, it discusses [1] the principles of bioenergetics including thermodynamics, phosphoryl group transfers, and oxidation-reduction reactions; [2] how ATP and other phosphorylated compounds are used to drive cellular processes; and [3] how electrons flow through metabolic pathways and soluble electron carriers to provide energy for biological work. It concludes by outlining topics to be covered in the next chapter on glycolysis and carbohydrate catabolism.
Cellular respiration involves a series of reactions that transfer electrons from glucose and other fuels to oxygen to generate energy in the form of ATP. It includes glycolysis, where glucose is partially oxidized to pyruvate, producing a small amount of ATP. Glycolysis involves phosphorylation of glucose, lysis to break it into triose phosphates, and oxidation of the phosphates through electron removal by NAD+, generating NADH. The pyruvate then undergoes oxidative decarboxylation during later stages of cellular respiration.
This document provides an overview of the course content for BMB 2101: Metabolism and Human Nutrition. The 3-credit course covers topics related to bioenergetics including definitions, types of bioenergetic reactions, metabolism, laws of bioenergetics, free energy, entropy, the TCA cycle, ATP-ADP cycle, and ATP as an energy carrier. The course aims to explain how energy is transferred and involved in chemical bond formation in cells, tissues, and organisms. Key areas of study are cellular respiration, photosynthesis, and how food energy is released and converted to ATP.
The document discusses bioenergetics and the electron transport chain. It begins with an introduction to bioenergetics and its history. It then describes the electron transport chain, including the four complexes, carriers that transport electrons and protons, and how a proton gradient is generated. Iron-sulfur proteins and cytochromes are metalloproteins that transport electrons in the electron transport chain.
Energy flows through living cells in various forms and is used to drive important cellular functions. [1] All cells use energy for movement, synthesis of molecules, and maintaining homeostasis. [2] Energy enters cells through photosynthesis which captures light energy and converts it into chemical energy stored in glucose. [3] Cells release energy through cellular respiration which breaks down glucose and other molecules to generate ATP, the cell's immediate energy currency.
This presentation was prepared in order to take Lecture of students in a summarised way and to provide them with the short, sweet and concise notes. It is based on PCI syllabus and is meant for B. Pharm. Second Semester...
This document discusses bioenergetics and how cells obtain and use energy. It explains that life requires energy to perform functions like muscle movement and cell growth. Energy exists in kinetic or potential forms. Cells capture energy from exergonic reactions through ATP synthesis, then use that stored energy from ATP hydrolysis to drive endergonic reactions. The main energy pathways involve breaking down carbohydrates, lipids, and proteins to form acetyl-CoA, which feeds into the Krebs cycle to generate ATP. This allows cells to couple energy inputs from food molecules to the outputs required for cellular work.
This document provides an overview of chapter 8 from Campbell Biology, 9th edition, which discusses metabolism. It covers several key topics in 3 paragraphs or less:
Metabolism transforms matter and energy according to the laws of thermodynamics through metabolic pathways mediated by enzymes. Catabolic pathways release energy by breaking down molecules, while anabolic pathways use energy to build molecules. ATP powers cellular work by coupling exergonic reactions to endergonic reactions.
Enzymes speed up metabolic reactions by lowering activation energy. Each enzyme has a specific substrate that binds at its active site, orienting the reactants in a way that facilitates the reaction. Environmental factors like temperature and pH can impact an enzyme's activity by influencing its
This document provides an overview of metabolism and bioenergetics. It discusses how cells extract energy from reactions to perform work, and how metabolism involves thousands of chemical reactions catalyzed by enzymes. Metabolic pathways convert molecules through a series of steps, with catabolic pathways releasing energy and anabolic pathways requiring energy. The energy of reactions is discussed in terms of free energy, and how ATP powers cellular work by coupling exergonic reactions to endergonic processes through phosphorylation. Enzymes lower the activation energy of reactions to speed up metabolism.
Metabolism is the set of chemical reactions that occur in living organisms to sustain life. Energy from food fuels these reactions through the intermediary ATP. Enzymes catalyze reactions by lowering their activation energy. Regulation of enzyme activity controls metabolic pathways and maintains cellular homeostasis.
Microbial metabolism involves catabolic reactions that break down molecules and anabolic reactions that build them up. Enzymes catalyze these reactions and require energy from ATP hydrolysis. Cells generate ATP through glycolysis of glucose, the citric acid cycle, and oxidative phosphorylation during aerobic respiration. Fermentation pathways produce ATP without oxygen through alcohol or lactic acid production.
Metabolism refers to the chemical processes that take place inside cells, including anabolic pathways that build complex compounds and catabolic pathways that break them down. Energy transformations are studied in thermodynamics, with the first law stating energy is conserved and the second law that entropy increases. ATP is the main energy currency of cells, storing and transferring chemical energy through exergonic hydrolysis reactions. Enzymes speed up metabolic reactions by lowering their activation energy through selective binding to substrates in their active sites. Feedback inhibition controls metabolic pathways by turning them off when a product reaches a threshold concentration.
1. Metabolism transforms matter and energy through chemical reactions within organisms, subject to the laws of thermodynamics. 2. Metabolic pathways are organized into catabolic pathways that break down molecules and release energy, and anabolic pathways that use energy to build molecules. 3. ATP powers cellular work by coupling exergonic reactions like its own hydrolysis to drive endergonic reactions like protein synthesis.
This presentation discusses microbial metabolism. It begins by defining metabolism as the sum of all chemical reactions within a cell and separates metabolism into catabolism, which releases energy, and anabolism, which uses that energy for biosynthesis. The key points are that cells use exergonic reactions to power endergonic reactions, with ATP serving as the energy currency. Metabolic pathways involve enzymes, electron carriers like NADH, and precursor metabolites that can be used for biosynthesis or completely oxidized for energy. Central pathways discussed include glycolysis, the pentose phosphate pathway, and the tricarboxylic acid cycle.
This document discusses bioenergetics and energy production through the TCA (Krebs) cycle. It defines bioenergetics as the part of biochemistry concerned with energy flow through living systems. It explains that living organisms obtain energy through breaking chemical bonds and oxidizing materials, often with oxygen. The energy is used to produce ATP, which acts as an energy battery. The TCA cycle is described as a series of chemical reactions that starts and ends with oxaloacetate, and produces 1 ATP, 3 NADH, and 1 FADH2 per turn to generate energy.
This document summarizes key concepts in bioenergetics and cellular respiration. It discusses how living organisms obtain and use energy through redox reactions and electron carriers like ATP. Photosynthesis and cellular respiration are introduced as the two main pathways of energy transformation. Photosynthesis uses energy from sunlight to synthesize glucose from carbon dioxide and water, while cellular respiration breaks down glucose to release energy through glycolysis, the Krebs cycle, and the electron transport chain. The document aims to explain the basic processes of how energy is transformed and utilized in living cells and organisms.
Organisms obtain energy through cellular processes like cellular respiration and photosynthesis. Cellular respiration breaks down food molecules to release energy, some as heat and some stored as ATP, which cells can use like money. Photosynthesis uses light energy from the sun to produce food molecules. Autotrophs like plants can produce their own food using photosynthesis, while heterotrophs must ingest food to get energy through cellular respiration.
The study of energy in living systems (environments) and the organisms (plants and animals) that utilize them.
I'm a st.Xavier's student . i think this ppt will be helpful to the others. Because this is needed in our daily life.
Bioenergetics is the study of energy transformations in living systems. Organisms need energy for physiological activities, which involve chemical reactions. Energy is utilized or generated in these reactions according to the laws of thermodynamics. Light provides energy for all organisms, as green plants capture light energy and convert it into chemical energy stored in glucose. Adenosine triphosphate (ATP) acts as the energy currency of cells, containing energy in its phosphate bonds. ATP transfers energy between energy-releasing and energy-consuming reactions through phosphorylation, the addition of phosphate groups. There are three types of phosphorylation: photophosphorylation using sunlight, and oxidative and substrate phosphorylation using energy from oxidation or substrate hydrolysis.
1) The document discusses light-dependent (photosynthetic) generators of proton potential, specifically focusing on the photosynthetic apparatus of purple bacteria.
2) Photosynthesis in purple bacteria involves a light-dependent cyclic redox chain where absorption of light by bacteriochlorophyll leads to electron transfer across the membrane, generating a proton gradient.
3) Key components of the redox chain include bacteriochlorophyll dimer and monomer, bacteriopheophytin, ubiquinone, cytochromes, and a nonheme iron-sulfur protein that facilitate electron transfer and proton pumping across the membrane.
The document summarizes key topics in biochemistry including metabolism, bioenergetics, and biochemical pathways. Specifically, it discusses [1] the principles of bioenergetics including thermodynamics, phosphoryl group transfers, and oxidation-reduction reactions; [2] how ATP and other phosphorylated compounds are used to drive cellular processes; and [3] how electrons flow through metabolic pathways and soluble electron carriers to provide energy for biological work. It concludes by outlining topics to be covered in the next chapter on glycolysis and carbohydrate catabolism.
Cellular respiration involves a series of reactions that transfer electrons from glucose and other fuels to oxygen to generate energy in the form of ATP. It includes glycolysis, where glucose is partially oxidized to pyruvate, producing a small amount of ATP. Glycolysis involves phosphorylation of glucose, lysis to break it into triose phosphates, and oxidation of the phosphates through electron removal by NAD+, generating NADH. The pyruvate then undergoes oxidative decarboxylation during later stages of cellular respiration.
This document provides an overview of the course content for BMB 2101: Metabolism and Human Nutrition. The 3-credit course covers topics related to bioenergetics including definitions, types of bioenergetic reactions, metabolism, laws of bioenergetics, free energy, entropy, the TCA cycle, ATP-ADP cycle, and ATP as an energy carrier. The course aims to explain how energy is transferred and involved in chemical bond formation in cells, tissues, and organisms. Key areas of study are cellular respiration, photosynthesis, and how food energy is released and converted to ATP.
The document discusses bioenergetics and the electron transport chain. It begins with an introduction to bioenergetics and its history. It then describes the electron transport chain, including the four complexes, carriers that transport electrons and protons, and how a proton gradient is generated. Iron-sulfur proteins and cytochromes are metalloproteins that transport electrons in the electron transport chain.
Energy flows through living cells in various forms and is used to drive important cellular functions. [1] All cells use energy for movement, synthesis of molecules, and maintaining homeostasis. [2] Energy enters cells through photosynthesis which captures light energy and converts it into chemical energy stored in glucose. [3] Cells release energy through cellular respiration which breaks down glucose and other molecules to generate ATP, the cell's immediate energy currency.
This presentation was prepared in order to take Lecture of students in a summarised way and to provide them with the short, sweet and concise notes. It is based on PCI syllabus and is meant for B. Pharm. Second Semester...
This document discusses bioenergetics and how cells obtain and use energy. It explains that life requires energy to perform functions like muscle movement and cell growth. Energy exists in kinetic or potential forms. Cells capture energy from exergonic reactions through ATP synthesis, then use that stored energy from ATP hydrolysis to drive endergonic reactions. The main energy pathways involve breaking down carbohydrates, lipids, and proteins to form acetyl-CoA, which feeds into the Krebs cycle to generate ATP. This allows cells to couple energy inputs from food molecules to the outputs required for cellular work.
This document provides an overview of chapter 8 from Campbell Biology, 9th edition, which discusses metabolism. It covers several key topics in 3 paragraphs or less:
Metabolism transforms matter and energy according to the laws of thermodynamics through metabolic pathways mediated by enzymes. Catabolic pathways release energy by breaking down molecules, while anabolic pathways use energy to build molecules. ATP powers cellular work by coupling exergonic reactions to endergonic reactions.
Enzymes speed up metabolic reactions by lowering activation energy. Each enzyme has a specific substrate that binds at its active site, orienting the reactants in a way that facilitates the reaction. Environmental factors like temperature and pH can impact an enzyme's activity by influencing its
This document provides an overview of metabolism and bioenergetics. It discusses how cells extract energy from reactions to perform work, and how metabolism involves thousands of chemical reactions catalyzed by enzymes. Metabolic pathways convert molecules through a series of steps, with catabolic pathways releasing energy and anabolic pathways requiring energy. The energy of reactions is discussed in terms of free energy, and how ATP powers cellular work by coupling exergonic reactions to endergonic processes through phosphorylation. Enzymes lower the activation energy of reactions to speed up metabolism.
Metabolism is the set of chemical reactions that occur in living organisms to sustain life. Energy from food fuels these reactions through the intermediary ATP. Enzymes catalyze reactions by lowering their activation energy. Regulation of enzyme activity controls metabolic pathways and maintains cellular homeostasis.
Microbial metabolism involves catabolic reactions that break down molecules and anabolic reactions that build them up. Enzymes catalyze these reactions and require energy from ATP hydrolysis. Cells generate ATP through glycolysis of glucose, the citric acid cycle, and oxidative phosphorylation during aerobic respiration. Fermentation pathways produce ATP without oxygen through alcohol or lactic acid production.
Metabolism refers to the chemical processes that take place inside cells, including anabolic pathways that build complex compounds and catabolic pathways that break them down. Energy transformations are studied in thermodynamics, with the first law stating energy is conserved and the second law that entropy increases. ATP is the main energy currency of cells, storing and transferring chemical energy through exergonic hydrolysis reactions. Enzymes speed up metabolic reactions by lowering their activation energy through selective binding to substrates in their active sites. Feedback inhibition controls metabolic pathways by turning them off when a product reaches a threshold concentration.
1. Metabolism transforms matter and energy through chemical reactions within organisms, subject to the laws of thermodynamics. 2. Metabolic pathways are organized into catabolic pathways that break down molecules and release energy, and anabolic pathways that use energy to build molecules. 3. ATP powers cellular work by coupling exergonic reactions like its own hydrolysis to drive endergonic reactions like protein synthesis.
This presentation discusses microbial metabolism. It begins by defining metabolism as the sum of all chemical reactions within a cell and separates metabolism into catabolism, which releases energy, and anabolism, which uses that energy for biosynthesis. The key points are that cells use exergonic reactions to power endergonic reactions, with ATP serving as the energy currency. Metabolic pathways involve enzymes, electron carriers like NADH, and precursor metabolites that can be used for biosynthesis or completely oxidized for energy. Central pathways discussed include glycolysis, the pentose phosphate pathway, and the tricarboxylic acid cycle.
Cells require constant energy to maintain their internal organization and carry out metabolic reactions. This energy is primarily derived from food and is transformed and stored in ATP molecules, which act as the "energy currency" of cells. Enzymes catalyze metabolic reactions and help minimize energy loss. The chloroplasts and mitochondria work together to transfer energy from sunlight through photosynthesis into cellular respiration to power the energy needs of organisms.
This document discusses photosynthesis and cellular respiration. It explains that photosynthesis uses light energy, carbon dioxide, and water to produce glucose and oxygen through a series of reactions in chloroplasts. Cellular respiration uses glucose and oxygen to produce energy through breakdown of organic compounds. The rate of photosynthesis is affected by factors like light intensity, carbon dioxide levels, and temperature.
Metabolism involves the chemical processes that take place in organisms. There are two main types of metabolic pathways - catabolic pathways that break down molecules and release energy, and anabolic pathways that use energy to build molecules. Cellular respiration uses catabolic pathways to break down glucose and other food molecules, releasing energy that is captured in ATP. There are four main stages of cellular respiration: glycolysis, pyruvate oxidation, the citric acid cycle, and the electron transport chain. When oxygen is absent, cells carry out anaerobic respiration like lactic acid fermentation or alcoholic fermentation to regenerate NAD+ and allow glycolysis to continue producing a small amount of ATP.
This document discusses energy and key energy transformations in living things. It covers:
1) Energy transformations like cellular respiration and photosynthesis that convert energy from one form to another. Photosynthesis converts solar energy to glucose and cellular respiration converts glucose to ATP.
2) The two main types of energy - potential and kinetic. Potential energy is stored while kinetic energy is in use. Examples like chemical bonds in sugars store potential energy.
3) Metabolism and the metabolic pathways of catabolism and anabolism. Catabolism breaks down molecules and releases energy while anabolism uses energy to build molecules.
4) ATP (adenosine triphosphate) serves as a key source of energy for
This document provides an overview of cellular metabolism, including cellular respiration and photosynthesis. It discusses various topics such as metabolism, energy, endergonic and exergonic reactions, ATP, enzymes, cellular respiration, glycolysis, the Krebs cycle, the electron transport chain, and chemiosmosis. The key points covered are that cellular respiration converts glucose into ATP through glycolysis, the Krebs cycle, and the electron transport chain. Glycolysis produces 2 ATP per glucose and occurs in the cytoplasm, while the other stages occur in the mitochondria and produce much more ATP through oxidative phosphorylation as electrons are transferred through the electron transport chain.
The document provides an overview of metabolism and energy transformation in cells. It discusses key concepts including:
1) Metabolism transforms matter and energy through chemical reactions catalyzed by enzymes. Metabolic pathways are organized to either release or absorb energy through catabolic and anabolic reactions.
2) ATP powers cellular work by coupling exergonic reactions like ATP hydrolysis to endergonic reactions like biosynthesis. Enzymes lower the activation energy of reactions and speed up metabolic pathways.
3) The first and second laws of thermodynamics govern energy transformations in cells. Free energy changes determine whether reactions are spontaneous. While cells increase disorder, living organisms maintain local reductions in entropy.
A comprehensive coverage of Enzymes including basics, mechanisms of enzyme catalysis, enzyme inhibition and clinical applications, mostly based on Stryer- Biochemistry. The slides were intended for MBBS teaching, but should benefit the students of Biochemistry and allied sciences.
Prepared in Sept 2015
Metabolism refers to the chemical processes that take place inside cells, including thousands of reactions that build up or break down complex compounds. These anabolic and catabolic pathways are concerned with managing the cell's energy and resources. Metabolism involves the conversion of energy from one form to another, as governed by the laws of thermodynamics. ATP acts as the main energy currency, using energy released from its phosphate bonds to power cellular work through exergonic reactions. Enzymes are crucial to metabolism as they catalyze reactions and allow them to proceed faster by lowering their activation energy. Metabolic pathways are regulated through feedback inhibition which turns pathways off once a threshold of end products has been reached.
1. Cellular respiration is the process that releases energy from food in the presence of oxygen. It involves the breakdown of glucose and other food molecules, capturing some energy to produce ATP and other compounds while releasing carbon dioxide and water.
2. ATP is the "energy currency" of cells. It is used to store and transport chemical energy within cells to power energy-requiring cellular processes. ATP is regenerated through catabolic reactions when its phosphate bonds are broken.
3. NADH and FADH2 act as electron carriers that shuttle energy extracted from nutrients to sites of ATP production through oxidative phosphorylation. NADPH similarly transports energy but for biosynthesis rather than ATP production.
8 - Metabolism and Transfering Energy - Part OneAhmad V.Kashani
Metabolism involves the chemical reactions that take place in organisms to sustain life. These reactions occur along metabolic pathways and either break down molecules through catabolism to release energy, or build molecules through anabolism by consuming energy. Adenosine triphosphate (ATP) is used to power cellular work by storing and transferring energy from exergonic reactions through its phosphate bonds. Enzymes regulate metabolic reactions by lowering their activation energy and increasing reaction rates in their active sites. Environmental factors and feedback inhibition regulate enzymatic activity and metabolic pathways.
The document provides an overview of metabolism and energy transformations in cells. It discusses how (1) cells extract and use energy to perform work through thousands of chemical reactions organized into metabolic pathways, (2) the laws of thermodynamics govern energy transformations with energy being conserved but entropy increasing, and (3) ATP powers cellular work by coupling exergonic reactions like its hydrolysis to endergonic reactions like transport or synthesis through energy transfer.
Mitochondria & choloroplat- Energy Harness Final old microsoft version.pptJanzaib
This document discusses the functions of cell organelles in obtaining and utilizing energy from food. Mitochondria and chloroplasts play key roles. Mitochondria break down sugars and fats through glycolysis, the citric acid cycle, and the electron transport chain to generate ATP. Chloroplasts use photosynthesis to harness sunlight to produce sugars from CO2 and release oxygen. Photosynthesis involves light and dark reactions that generate ATP and NADPH to fix carbon and produce glucose that can be stored or used for energy. Both organelles breakdown and regenerate ATP to power cellular work through membrane-based mechanisms.
Photosynthesis is the process by which plants use energy from sunlight to convert carbon dioxide and water into glucose and oxygen. Chlorophyll in plant cells absorbs sunlight and transfers its energy to electrons. The light-dependent reactions use this energy to produce ATP, NADPH, and oxygen. The light-independent Calvin cycle then uses ATP and NADPH to produce glucose and regenerate the starting molecules to continue the cycle. Photosynthesis occurs in plant cell organelles called chloroplasts, within membranes called thylakoids that contain the light-dependent reactions, and the surrounding stroma that contains the light-independent Calvin cycle.
Digital Marketing Trends in 2024 | Guide for Staying AheadWask
https://www.wask.co/ebooks/digital-marketing-trends-in-2024
Feeling lost in the digital marketing whirlwind of 2024? Technology is changing, consumer habits are evolving, and staying ahead of the curve feels like a never-ending pursuit. This e-book is your compass. Dive into actionable insights to handle the complexities of modern marketing. From hyper-personalization to the power of user-generated content, learn how to build long-term relationships with your audience and unlock the secrets to success in the ever-shifting digital landscape.
Skybuffer SAM4U tool for SAP license adoptionTatiana Kojar
Manage and optimize your license adoption and consumption with SAM4U, an SAP free customer software asset management tool.
SAM4U, an SAP complimentary software asset management tool for customers, delivers a detailed and well-structured overview of license inventory and usage with a user-friendly interface. We offer a hosted, cost-effective, and performance-optimized SAM4U setup in the Skybuffer Cloud environment. You retain ownership of the system and data, while we manage the ABAP 7.58 infrastructure, ensuring fixed Total Cost of Ownership (TCO) and exceptional services through the SAP Fiori interface.
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
This presentation provides valuable insights into effective cost-saving techniques on AWS. Learn how to optimize your AWS resources by rightsizing, increasing elasticity, picking the right storage class, and choosing the best pricing model. Additionally, discover essential governance mechanisms to ensure continuous cost efficiency. Whether you are new to AWS or an experienced user, this presentation provides clear and practical tips to help you reduce your cloud costs and get the most out of your budget.
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfMalak Abu Hammad
Discover how MongoDB Atlas and vector search technology can revolutionize your application's search capabilities. This comprehensive presentation covers:
* What is Vector Search?
* Importance and benefits of vector search
* Practical use cases across various industries
* Step-by-step implementation guide
* Live demos with code snippets
* Enhancing LLM capabilities with vector search
* Best practices and optimization strategies
Perfect for developers, AI enthusiasts, and tech leaders. Learn how to leverage MongoDB Atlas to deliver highly relevant, context-aware search results, transforming your data retrieval process. Stay ahead in tech innovation and maximize the potential of your applications.
#MongoDB #VectorSearch #AI #SemanticSearch #TechInnovation #DataScience #LLM #MachineLearning #SearchTechnology
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
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HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
- Reducing license cost by finding and fixing misconfigurations and superfluous accounts
- How do CCB and CCX licenses really work?
- Understanding the DLAU tool and how to best utilize it
- Tips for common problem areas, like team mailboxes, functional/test users, etc
- Practical examples and best practices to implement right away
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During the hour, we’ll take you through:
Guest Speaker Segment with Hannah Barrington: Dive into the world of dynamic real estate marketing with Hannah, the Marketing Manager at Workspace Group. Hear firsthand how their team generates engaging descriptions for thousands of office units by integrating diverse data sources—from PDF floorplans to web pages—using FME transformers, like OpenAIVisionConnector and AnthropicVisionConnector. This use case will show you how GenAI can streamline content creation for marketing across the board.
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Driving Business Innovation: Latest Generative AI Advancements & Success Story
Chapter5 sections+1 4
1. Albia Dugger • Miami Dade College
Cecie Starr
Christine Evers
Lisa Starr
www.cengage.com/biology/starr
Chapter 5
Ground Rules of Metabolism
(Sections 5.1 - 5.4)
2. 5.1 A Toast to
Alcohol Dehydrogenase
• Metabolic processes build and break down organic molecules
such as ethanol and other toxins
• Alcohol breakdown directly damages liver cells, and interferes
with normal processes of metabolism
• Currently the most serious drug problem on college
campuses is binge drinking
3. Alcohol Metabolism
• The enzyme
alcohol
dehydrogenase
helps the liver
break down toxic
alcohols (ethanol)
4. 5.2 Energy and the World of Life
• There are many forms of energy:
• Kinetic energy, potential energy
• Light, heat, electricity, motion
• Energy cannot be created or destroyed (first law of
thermodynamics)
• Energy can be converted from one form to another and thus
transferred between objects or systems
5. Energy Disperses
• Energy tends to disperse spontaneously (second law of
thermodynamics)
• A bit disperses at each energy transfer, usually as heat
• Entropy is a measure of how dispersed the energy of a
system has become
6. Key Terms
• energy
• The capacity to do work
• kinetic energy
• The energy of motion
• entropy
• Measure of how much the energy of a system is dispersed
7. Key Terms
• first law of thermodynamics
• Energy cannot be created or destroyed
• second law of thermodynamics
• Energy tends to disperse spontaneously
9. Entropy
• Entropy tends to
increase, but the total
amount of energy in any
system always stays the
same
10. Fig. 5.3, p. 76
Entropy
Time
heat
energy
Stepped Art
Entropy
11. Work
• Work occurs as a result of an energy transfer
• A plant converts light energy to chemical energy in
photosynthesis
• Most other cellular work occurs by transfer of chemical energy
from one molecule to another (such as transferring chemical
energy from ATP to other molecules)
12. Energy’s One-Way Flow
• Living things maintain their organization only as long as they
harvest energy from someplace else
• Energy flows in one direction through the biosphere, starting
mainly from the sun, then into and out of ecosystems
• Producers and then consumers use energy to assemble,
rearrange, and break down organic molecules that cycle
among organisms throughout ecosystems
13. Energy Conversion
• It takes 10,000 pounds
of feed to raise a 1,000-
pound steer
• About 15% of energy in
food builds body mass;
the rest is lost as heat
during energy
conversions
14. Energy Flow
• Energy flows from the
environment into living
organisms, and back to
the environment
• Materials cycle among
producers and
consumers
15. Fig. 5.5, p. 77
Consumers
animals, most fungi,
many protists, bacteria
nutrient cycling
Producers
plants and other
self-feeding organisms
sunlight
energy
Energy Flow
17. Potential Energy
• Energy’s spontaneous dispersal is resisted by chemical bonds
• Energy in chemical bonds is a type of potential energy,
because it can be stored
• potential energy
• Stored energy
18. Key Concepts
• Energy Flow
• Organisms maintain their organization only by continually
harvesting energy from their environment
• ATP couples reactions that release usable energy with
reactions that require it
20. 5.3 Energy in the Molecules of Life
• Every chemical bond holds energy – the amount of energy
depends on which elements are taking part in the bond
• Cells store and retrieve free energy by making and breaking
chemical bonds in metabolic reactions, in which reactants
are converted to products
21. Key Terms
• reaction
• Process of chemical change
• reactant
• Molecule that enters a reaction
• product
• A molecule that remains at the end of a reaction
22. Chemical Bookkeeping
• In equations that represent chemical reactions, reactants are
written to the left of an arrow that points to the products
• A number before a formula indicates the number of molecules
• The same number of atoms that enter a reaction remain at
the reaction’s end
26. Energy In, Energy Out
• In most reactions, free energy of reactants differs from free
energy of products
• Reactions in which reactants have less free energy than
products are endergonic – they will not proceed without a
net energy input
• Reactions in which reactants have greater free energy than
products are exergonic – they end with a net release of free
energy
27. Key Terms
• endergonic
• “Energy in”
• Reaction that converts molecules with lower energy to
molecules with higher energy
• Requires net input of free energy to proceed
• exergonic
• “Energy out”
• Reaction that converts molecules with higher energy to
molecules with lower energy
• Ends with a net release of free energy
29. Fig. 5.7, p. 78
Freeenergy
energy out
energy in
2H2O
O22H2
1
2
2H2O
Energy In, Energy Out
30. Why Earth Does Not Go Up in Flames
• Earth is rich in oxygen—and in potential exergonic reactions;
why doesn’t it burst into flames?
• Luckily, energy is required to break chemical bonds of
reactants, even in an exergonic reaction
• activation energy
• Minimum amount of energy required to start a reaction
• Keeps exergonic reactions from starting spontaneously
32. Fig. 5.8, p. 79
O2
Freeenergy
2H2
Activation energy
Products: 2H2ODifference between
free energy of
reactants and products
Reactants:
Activation Energy
34. ATP—The Cell’s Energy Currency
• ATP is the main currency in a cell’s energy economy
• ATP (Adenosine triphosphate)
• Nucleotide with three phosphate groups linked by high-
energy bonds
• An energy carrier that couples endergonic with exergonic
reactions in cells
36. Fig. 5.9a, p. 79
A Structure of ATP.
ribose
adenine
three phosphate
groups
ATP
37. Phosphorylation
• When a phosphate group is transferred from ATP to another
molecule, energy is transferred along with the phosphate
• Phosphate-group transfers (phosphorylations) to and from
ATP couple exergonic reactions with endergonic ones
• phosphorylation
• Addition of a phosphate group to a molecule
• Occurs by the transfer of a phosphate group from a donor
molecule such as ATP
39. Fig. 5.9b, p. 79
B After ATP loses one phosphate group, the nucleotide is
ADP (adenosine diphosphate); after losing two phosphate
groups, it is AMP (adenosine monophosphate)
ribose
adenine
AMP
ATPADP
ATP and ADP
40. ATP/ADP Cycle
• Cells constantly use up ATP to drive endergonic reactions, so
they constantly replenish it by the ATP/ADP cycle
• ATP/ADP cycle
• Process by which cells regenerate ATP
• ADP forms when ATP loses a phosphate group, then ATP
forms again as ADP gains a phosphate group
42. Fig. 5.9c, p. 79
energy out
ADP + phosphate
energy in
C ATP forms by endergonic reactions. ADP forms again
when ATP energy is transferred to another molecule
along with a phosphate group. Energy from such
transfers drives cellular work.
ATP/ADP Cycle
44. 5.4 How Enzymes Work
• Enzymes makes a reaction run much faster than it would on
its own, without being changed by the reaction
• catalysis
• The acceleration of a reaction rate by a molecule that is
unchanged by participating in the reaction
• Most enzymes are proteins, but some are RNAs
45. Substrates
• Each enzyme recognizes specific reactants, or substrates,
and alters them in a specific way
• substrate
• A molecule that is specifically acted upon by an enzyme
46. Active Sites
• Enzyme specificity occurs because an enzyme’s polypeptide
chains fold up into one or more active sites
• An active site is complementary in shape, size, polarity, and
charge to the enzyme’s substrate
• active site
• Pocket in an enzyme where substrates bind and a reaction
occurs
49. Fig. 5.10a, p. 80
active site
enzyme
A Like other enzymes,
hexokinase’s active sites bind
and alter specific substrates. A
model of the whole enzyme is
shown to the left.
An Active Site
51. Fig. 5.10b, p. 80
reactant(s)
B A close-up shows glucose
and phosphate meeting inside
the enzyme’s active site. The
microenvironment of the site
favors a reaction between the
two substrate molecules.
An Active Site
53. Fig. 5.10c, p. 80
product(s)
C Here, the glucose has
bonded with the phosphate.
The product of this reaction,
glucose-6-phosphate, is
shown leaving the active site.
An Active Site
54. Lowering Activation Energy
• Enzymes lower activation energy in four ways:
• Bringing substrates closer together
• Orienting substrates in positions that favor reaction
• Inducing the fit between a substrate and the enzyme’s
active site (induced-fit model)
• Shutting out water molecules
• induced-fit model
• Substrate binding to an active site improves the fit
between the two
56. Fig. 5.11, p. 80
Freeenergy
Reactants
Products
Transition state
Activation energy
with enzyme
Activation energy
without enzyme
Time
Lowering Activation Energy
58. Effects of Temperature, pH, and Salinity
• Each type of enzyme works best within a characteristic range
of temperature, pH, and salt concentration:
• Adding heat energy boosts free energy, increasing
reaction rate (within a given range)
• Most human enzymes have an optimal pH between 6 and
8 (e.g. pepsin functions only in stomach fluid, pH 2)
• Too much or too little salt disrupts hydrogen bonding that
holds an enzyme in its three-dimensional shape
60. Fig. 5.12, p. 81
Temperature
Enzymeactivity
temperature-
sensitive
tyrosinase
normal
tyrosinase
40°C (104°F)30°C (86°F)20°C (68°F)
Enzymes and Temperature
64. Help From Cofactors
• Most enzymes require cofactors, which are metal ions or
organic coenzymes in order to function
• cofactor
• A metal ion or a coenzyme that associates with an enzyme
and is necessary for its function
• coenzyme
• An organic molecule that is a cofactor
65. Coenzymes and Cofactors
• Coenzymes may be modified by taking part in a reaction
• Example: NAD+
becomes NADH by accepting electrons
and a hydrogen atom in a reaction
• Cofactors are metal ions
• Example: The iron atom at the center of each heme
• In the enzyme catalase, iron pulls on the substrate’s
electrons, which brings on the transition state
66. Antioxidants
• Cofactors in some antioxidants help them stop reactions
with oxygen that produce free radicals (harmful atoms or
molecules with unpaired electrons)
• Example: Catalase is an antioxidant
• antioxidant
• Substance that prevents molecules from reacting with
oxygen
67. Key Concepts
• How Enzymes Work
• Enzymes tremendously increase the rate of metabolic reactions
• Cofactors assist enzymes, and environmental factors such as
temperature, salt, and pH can influence enzyme function
Figure 5.1 Alcohol metabolism. Alcohol dehydrogenase helps the body break down toxic alcohols such as ethanol. This enzyme makes it possible for humans to drink beer, wine, and other alcoholic beverages
Figure 5.2 Demonstration of a familiar type of energy: motion, or kinetic energy.
Figure 5.3 Entropy. Entropy tends to increase, but the total amount of energy in any system always stays the same
Figure 5.3 Entropy. Entropy tends to increase, but the total amount of energy in any system always stays the same
Figure 5.4 It takes more than 10,000 pounds of soybeans and corn to raise a 1,000-pound steer. Where do the other 9,000 pounds go? About half of the steer’s food is indigestible. The animal’s body breaks down molecules in the remaining half to access energy stored in chemical bonds. Only about 15% of that energy goes toward building body mass. The rest is lost during energy conversions, as heat.
Figure 5.5 Energy flows from the environment into living organisms, and then back to the environment. The flow drives a cycling of materials among producers and consumers.
Figure 5.6 Chemical bookkeeping. In equations that represent chemical reactions, reactants are written to the left of an arrow that points to the products. A number before a formula indicates the number of molecules. Atoms shuffle around in a reaction, but they never disappear: The same number of atoms that enter a reaction remain at the reaction’s end.
Figure 5.7 Energy inputs and outputs in chemical reactions. 1 Endergonic reactions convert molecules with lower energy to molecules with higher energy, so they require a net energy input in order to proceed. 2 Exergonic reactions convert molecules with higher energy to molecules with lower energy, so they end with a net energy output.
Figure 5.8 Activation energy. Most reactions will not begin without an input of activation energy, which is shown here as a bump in an energy hill. In this example, the reactants have more energy than the products. Activation energy keeps this and other exergonic reactions from starting spontaneously.
Figure 5.9 ATP, the energy currency of cells.
Figure 5.9 ATP, the energy currency of cells.
Figure 5.9 ATP, the energy currency of cells.
Figure 5.10 An example of an active site. This one is in a hexokinase, an enzyme that phosphorylates glucose and other six-carbon sugars.
Figure 5.10 An example of an active site. This one is in a hexokinase, an enzyme that phosphorylates glucose and other six-carbon sugars.
Figure 5.10 An example of an active site. This one is in a hexokinase, an enzyme that phosphorylates glucose and other six-carbon sugars.
Figure 5.10 An example of an active site. This one is in a hexokinase, an enzyme that phosphorylates glucose and other six-carbon sugars.
Figure 5.10 An example of an active site. This one is in a hexokinase, an enzyme that phosphorylates glucose and other six-carbon sugars.
Figure 5.10 An example of an active site. This one is in a hexokinase, an enzyme that phosphorylates glucose and other six-carbon sugars.
Figure 5.11 An enzyme enhances the rate of a reaction by lowering its activation energy.
Figure 5.12 Enzymes and temperature. Tyrosinase is involved in the production of melanin, a black pigment in skin cells. The form of this enzyme in Siamese cats is inactive above about 30ーC (86ーF), so the warmer parts of the cat’s body end up with less melanin, and lighter fur.
Figure 5.13 Enzymes and pH. Left, how pH affects three enzymes. Right, carnivorous plants of the genus Nepenthes grow in nitrogen-poor habitats. They secrete acids and protein-digesting enzymes into a fluid–filled cup that consists of a modified leaf. The enzymes release nitrogen from insects that are attracted to odors from the fluid and then drown in it. One of these enzymes functions best at pH 2.6.