This document summarizes key aspects of photosynthesis. It begins by explaining that life is powered by the sun through photosynthesis and that organisms obtain energy and carbon either through autotrophy or heterotrophy. It then describes the two stages of photosynthesis - the light reactions which convert solar energy to ATP and NADPH and the Calvin cycle which uses this energy to fix carbon from CO2 into sugars. The document provides details on chloroplast structure, the electron transport chain, and mechanisms like cyclic and noncyclic electron flow. It also discusses C3, C4, and CAM carbon fixation pathways and the importance of photosynthesis for providing oxygen and energy to living things globally.
1) Photosynthesis converts light energy to chemical energy stored in glucose through two stages: the light-dependent reactions and light-independent reactions.
2) In the light-dependent reactions, light energy is absorbed by antennae pigments and transferred through photosystems I and II to excite electrons, which is used to generate ATP and NADPH via electron transport. Water is also split to release protons and oxygen.
3) The ATP and NADPH produced in the light-dependent reactions will then be used in the light-independent reactions to convert carbon dioxide into glucose.
The document discusses light and shadows. It defines light as a form of energy and light sources as objects that produce light. Light sources can be natural, like the sun, or artificial, like lamps. When a light source shines on an opaque object, it creates a shadow on the surface behind the object by blocking the light's path. Reflection occurs when light hits the surface of an object and bounces off in the same or different directions depending on whether the surface is smooth or rough.
The document summarizes the process of photosynthesis. It describes the structure of chloroplasts, including the chloroplast envelope, internal tykaloids, stroma, and grana. It explains that photosynthesis uses light energy from the sun to produce chemical energy in the form of ATP and NADPH, and that this process occurs in the chloroplasts. It lists several factors that affect the rate of photosynthesis, including temperature, light intensity, and carbon dioxide concentration.
The document summarizes water transport through plants. It describes how water is absorbed through root hairs into the xylem and transported upwards. Water moves from root hair cells to the cortex and endodermis by osmosis. In the stem, water is transported through xylem vessels by tension from the leaves. Water then diffuses out of xylem cells in the leaves down a concentration gradient to be used in photosynthesis.
This document provides an overview of bioenergetics and the flow of energy through living systems. It defines key terms like bioenergetics, energy, producers, consumers, and energy-giving molecules. Producers, or autotrophs, are able to produce their own food through photosynthesis and provide energy for other organisms. Consumers, or heterotrophs, consume producers or other consumers. Glucose and ATP are important energy-giving molecules, with ATP storing and transferring energy within cells. The document also briefly discusses the early history of experiments conducted to understand photosynthesis.
TRANSPORTATION IN PLANTS AND CIRCULATION IN ANIMALS.pptAvi's Micro World
Plants transport water and nutrients throughout their bodies using specialized tissues. Water and minerals are absorbed by root hairs and transported through the xylem from roots to stems and leaves. Food synthesized in the leaves is distributed throughout the plant via the phloem. Substances move between plant cells via diffusion, active transport, and osmosis according to concentration gradients. Root hairs, xylem, and phloem tissues allow nutrients and water to reach all parts of multicellular plants.
The document provides information about photosynthesis including:
1. Photosynthesis is the process by which plants, some bacteria, and some protistans use the energy from sunlight to produce sugar.
2. The primary product of photosynthesis is glucose, which is the source of carbohydrates like cellulose, starches, etc. Photosynthesis also produces oxygen, fats, proteins, and water soluble sugars.
3. Photosynthesis takes place in the chloroplasts of plant leaves. The chloroplasts contain chlorophyll and other pigments that absorb sunlight to drive a series of reactions that produce ATP and NADPH.
Cellular respiration involves the breakdown of glucose or other molecules to extract energy through a series of redox reactions. These reactions take place in the mitochondria, which contain an inner and outer membrane. The inner membrane contains cristae and enzymes that make up the electron transport chain (ETC), which pumps protons into the intermembrane space. This generates a proton gradient that is used by ATP synthase to produce ATP through oxidative phosphorylation. Glycolysis produces pyruvate and ATP in the cytosol. Pyruvate then enters the mitochondria and is converted to acetyl-CoA to feed into the Krebs cycle. The Krebs cycle produces NADH, FADH2, and GTP. These electron carriers are
1) Photosynthesis converts light energy to chemical energy stored in glucose through two stages: the light-dependent reactions and light-independent reactions.
2) In the light-dependent reactions, light energy is absorbed by antennae pigments and transferred through photosystems I and II to excite electrons, which is used to generate ATP and NADPH via electron transport. Water is also split to release protons and oxygen.
3) The ATP and NADPH produced in the light-dependent reactions will then be used in the light-independent reactions to convert carbon dioxide into glucose.
The document discusses light and shadows. It defines light as a form of energy and light sources as objects that produce light. Light sources can be natural, like the sun, or artificial, like lamps. When a light source shines on an opaque object, it creates a shadow on the surface behind the object by blocking the light's path. Reflection occurs when light hits the surface of an object and bounces off in the same or different directions depending on whether the surface is smooth or rough.
The document summarizes the process of photosynthesis. It describes the structure of chloroplasts, including the chloroplast envelope, internal tykaloids, stroma, and grana. It explains that photosynthesis uses light energy from the sun to produce chemical energy in the form of ATP and NADPH, and that this process occurs in the chloroplasts. It lists several factors that affect the rate of photosynthesis, including temperature, light intensity, and carbon dioxide concentration.
The document summarizes water transport through plants. It describes how water is absorbed through root hairs into the xylem and transported upwards. Water moves from root hair cells to the cortex and endodermis by osmosis. In the stem, water is transported through xylem vessels by tension from the leaves. Water then diffuses out of xylem cells in the leaves down a concentration gradient to be used in photosynthesis.
This document provides an overview of bioenergetics and the flow of energy through living systems. It defines key terms like bioenergetics, energy, producers, consumers, and energy-giving molecules. Producers, or autotrophs, are able to produce their own food through photosynthesis and provide energy for other organisms. Consumers, or heterotrophs, consume producers or other consumers. Glucose and ATP are important energy-giving molecules, with ATP storing and transferring energy within cells. The document also briefly discusses the early history of experiments conducted to understand photosynthesis.
TRANSPORTATION IN PLANTS AND CIRCULATION IN ANIMALS.pptAvi's Micro World
Plants transport water and nutrients throughout their bodies using specialized tissues. Water and minerals are absorbed by root hairs and transported through the xylem from roots to stems and leaves. Food synthesized in the leaves is distributed throughout the plant via the phloem. Substances move between plant cells via diffusion, active transport, and osmosis according to concentration gradients. Root hairs, xylem, and phloem tissues allow nutrients and water to reach all parts of multicellular plants.
The document provides information about photosynthesis including:
1. Photosynthesis is the process by which plants, some bacteria, and some protistans use the energy from sunlight to produce sugar.
2. The primary product of photosynthesis is glucose, which is the source of carbohydrates like cellulose, starches, etc. Photosynthesis also produces oxygen, fats, proteins, and water soluble sugars.
3. Photosynthesis takes place in the chloroplasts of plant leaves. The chloroplasts contain chlorophyll and other pigments that absorb sunlight to drive a series of reactions that produce ATP and NADPH.
Cellular respiration involves the breakdown of glucose or other molecules to extract energy through a series of redox reactions. These reactions take place in the mitochondria, which contain an inner and outer membrane. The inner membrane contains cristae and enzymes that make up the electron transport chain (ETC), which pumps protons into the intermembrane space. This generates a proton gradient that is used by ATP synthase to produce ATP through oxidative phosphorylation. Glycolysis produces pyruvate and ATP in the cytosol. Pyruvate then enters the mitochondria and is converted to acetyl-CoA to feed into the Krebs cycle. The Krebs cycle produces NADH, FADH2, and GTP. These electron carriers are
The document outlines a lesson plan on aerobic respiration that includes three main steps: glycolysis, the Krebs cycle, and the electron transport chain. The teacher will motivate students with a puzzle activity and divide them into groups to research and present on each step. An evaluation asks students to identify the processes, steps, and important molecules in aerobic respiration using an illustration. The lesson aims to help students understand and appreciate the importance of aerobic respiration for animals and plants.
Cellular respiration involves three main stages to break down glucose and produce ATP as energy. [1] Glycolysis converts glucose to pyruvate in the cytoplasm, producing a small amount of ATP. [2] The pyruvate then enters the mitochondrion, where the citric acid cycle further oxidizes it and produces more ATP and electron carriers. [3] Finally, the electron transport chain uses these carriers to pump protons across a membrane and produce a large amount of ATP through chemiosmosis. Overall, the process fully oxidizes one glucose molecule into 6 carbon dioxide molecules and produces 38 ATP.
Cellular respiration is a catabolic process that uses oxygen to break down glucose and other organic molecules to extract energy in the form of ATP. It occurs in four main stages: 1) glycolysis in the cytosol, 2) transport of pyruvate into the mitochondria, 3) the Krebs cycle in the mitochondrial matrix, and 4) the electron transport chain and oxidative phosphorylation on the inner mitochondrial membrane. The overall process produces 38 ATP molecules from complete oxidation of one glucose molecule.
1) The document provides a lesson on cellular respiration that uses simulations to explore the pathways of glycolysis, the Krebs cycle, and the electron transport chain.
2) Students will learn about the key molecules and enzymes involved in each pathway, how they extract energy from glucose, and the relative energetic content of molecules like ATP.
3) The lesson assesses student understanding with embedded questions and is designed to be used with TI-Nspire technology for interactive simulations and monitoring of student progress.
Cellular respiration is the process that releases energy from glucose in the presence of oxygen. It involves three main stages: glycolysis, the Krebs cycle, and the electron transport chain. Glycolysis breaks down glucose and produces a small amount of ATP. The Krebs cycle further breaks down the products of glycolysis and produces more ATP and electron carriers. During the electron transport chain, electrons are passed along a chain which pumps hydrogen ions across a membrane. This creates a proton gradient that is used by ATP synthase to produce large amounts of ATP from ADP and phosphate. The overall equation is that glucose and oxygen are broken down to produce carbon dioxide, water, and a large amount of ATP as energy.
The document discusses several topics related to population biology and human population growth, including:
1) Factors that influence population growth such as birth rates, death rates, and environmental limits. Populations exhibit either rapid exponential growth or slow steady growth depending on these factors.
2) Techniques scientists use to estimate population sizes such as sampling and mark-recapture when it is difficult to count all individuals.
3) Human population growth has increased rapidly over the past 150 years from 1 billion to over 7 billion currently due to declining death rates from improvements in health, education, and sanitation.
This document defines and describes different biomes, including terrestrial biomes like tundra, taiga, desert, grassland, temperate forest, and tropical rainforest as well as aquatic biomes like marine environments with photic and aphotic zones, estuaries, and freshwater biomes. It provides details on characteristic climate, plants, soils, and common animal species for each biome.
Cell cycle reproduction lecture with turning pointtas11244
Prokaryotes like bacteria reproduce through binary fission, where the cell duplicates its DNA and other components and then divides into two daughter cells. Eukaryotes undergo the cell cycle of interphase and mitosis, where interphase involves cell growth and DNA replication, followed by mitosis where the cell divides through the stages of prophase, metaphase, anaphase and telophase resulting in two identical daughter cells.
Photosynthesis is the process by which plants, algae and some bacteria use sunlight, water and carbon dioxide to produce oxygen and energy in the form of glucose. It takes place in two stages: the light-dependent reactions that use energy from sunlight to make ATP and NADPH, and the light-independent reactions known as the Calvin cycle that use ATP and NADPH to produce glucose from carbon dioxide. Chlorophyll, located in chloroplasts, absorbs sunlight and drives the light-dependent reactions that split water to produce oxygen, protons and electrons. The electrons are used to produce ATP and NADPH, which are then used in the Calvin cycle to reduce carbon dioxide to glucose.
The document describes a lesson plan activity where students act out the steps of cellular respiration. In the activity, students move between three tables representing the cytosol and mitochondria. At each table, they break down a glucose molecule and track the production of ATP, NADH, FADH2, carbon dioxide, and hydrogen ions. The goal is for students to demonstrate their understanding of aerobic respiration and how glucose and oxygen are used to produce ATP through glycolysis, the Krebs cycle, and the electron transport chain.
Meiosis gamete production with turning pointtas11244
Meiosis is a type of cell division that produces gametes, such as sperm or egg cells, with half the number of chromosomes. It involves two cell divisions: Meiosis I and Meiosis II. In Meiosis I, homologous chromosomes pair and may exchange genetic material through crossing over. The homologous chromosomes then separate, reducing the chromosome number by half. Meiosis II then separates the sister chromatids, resulting in four haploid daughter cells each with a single set of chromosomes.
The cell membrane controls what enters and exits the cell to maintain homeostasis. It is a selectively permeable bilayer made of phospholipids and embedded proteins. Small hydrophobic molecules and gases can pass through by diffusion down their concentration gradients, but most ions and larger molecules require transport proteins. Active transport uses ATP to move substances against their concentration gradients, such as the sodium-potassium pump. Endocytosis and exocytosis allow cells to ingest and secrete larger particles and molecules.
The document discusses cellular respiration, which is the process by which cells break down food molecules to produce energy in the form of ATP. It describes the three main stages of cellular respiration: glycolysis, the citric acid cycle, and the electron transport chain. Glycolysis breaks down glucose and occurs in the cytoplasm, producing a small amount of ATP. The citric acid cycle further breaks down molecules in the mitochondria, producing more ATP and electrons. The electron transport chain uses these electrons and oxygen to produce the most ATP through oxidative phosphorylation. Aerobic respiration requires oxygen while anaerobic respiration occurs without oxygen through fermentation.
1. This document describes experiments to study the effect of pH on the rate of fermentation in yeast. Students will set up solutions with yeast in buffers of varying pH and measure the amount of carbon dioxide produced over time.
2. The results will be recorded and two graphs will be made: one showing gas production over time for each pH, the other showing gas produced at 40 minutes for each pH. This will help determine the effect of pH on the rate of fermentation.
3. The effect of pH and possible mechanisms will be discussed, drawing on cell biology and metabolic knowledge.
This document summarizes the history and process of photosynthesis. It describes key discoveries such as Priestley observing that plants give off oxygen, and van Niel determining the reaction equation for photosynthesis in purple bacteria. It then explains the light and dark reactions of photosynthesis in detail, including Calvin's discovery of the Calvin cycle where carbon dioxide is incorporated into carbohydrates. The document also discusses different types of plants, including C3, C4, and CAM plants, and how they regulate photosynthesis through pathways like the Hatch-Slack cycle.
ATP, Photosynthesis, and Cellular Respirationlkocian
This document discusses energy flow through photosynthesis and cellular respiration. It begins by defining energy and the different forms it can take, including chemical energy stored in ATP. Photosynthesis uses light energy to convert carbon dioxide and water into glucose and oxygen through two reactions - the light-dependent reaction where ATP is produced, and the Calvin cycle where glucose is formed. Cellular respiration breaks down glucose and uses oxygen to release the energy stored in ATP through three stages - glycolysis, the Krebs cycle in the mitochondria, and the electron transport chain where a large amount of ATP is generated to store energy from food.
This document provides information about Module 5 of an alternative secondary education biology course on cellular respiration. The module contains 5 lessons that discuss how living organisms harvest energy stored in foods through cellular respiration. Key points covered include:
- Cellular respiration is the process where stored chemical energy in foods is converted to ATP in organisms.
- The mitochondria are where cellular respiration occurs in eukaryotic cells. They have inner and outer membranes with cristae infoldings containing protein complexes.
- Glycolysis is the first step where glucose is broken down, producing some ATP and NADH.
- An activity demonstrates how yeast cells respire and produce carbon dioxide from sugar, showing cellular respiration.
Cellular respiration occurs in three main stages to harvest energy from glucose and produce ATP. Stage 1 is glycolysis in the cytoplasm, which oxidizes glucose to pyruvate and generates 2 ATP and 2 NADH. Stage 2 is the citric acid cycle in the mitochondria, which completes glucose oxidation and generates more NADH and FADH2. Stage 3 is oxidative phosphorylation in the inner mitochondrial membrane, where electrons are transferred through an electron transport chain to generate ATP through chemiosmosis. Fermentation enables some ATP production without oxygen through glycolysis alone.
Cellular respiration involves the breakdown of glucose and other organic molecules to extract energy in the form of ATP. It occurs in three main stages: glycolysis, the Krebs cycle in the mitochondria, and oxidative phosphorylation along the electron transport chain. During aerobic respiration, glucose breakdown yields about 38 ATP molecules total. Without oxygen, anaerobic respiration produces less ATP but allows glycolysis to continue by converting pyruvate into other waste products like lactic acid.
Photosynthesis is the process by which plants, algae, and some bacteria use sunlight, water, and carbon dioxide to produce oxygen and energy in the form of glucose. It takes place in chloroplasts, which contain chlorophyll and other photosynthetic pigments. The light-dependent stage uses energy from sunlight to produce ATP and NADPH through photophosphorylation. The light-independent stage, also called the Calvin cycle, uses ATP and NADPH to fix carbon from carbon dioxide into organic molecules like glucose. Photosynthesis provides a critical energy source and oxygen for living organisms.
Photosynthesis occurs in chloroplasts within plant cells. Light energy is absorbed by chlorophyll and other pigments in the thylakoid membranes and used to convert water and carbon dioxide into oxygen and energy-rich glucose. The light reactions use photosystems to produce ATP and NADPH from water, while the Calvin cycle fixes carbon into glucose using these products in the stroma.
The document outlines a lesson plan on aerobic respiration that includes three main steps: glycolysis, the Krebs cycle, and the electron transport chain. The teacher will motivate students with a puzzle activity and divide them into groups to research and present on each step. An evaluation asks students to identify the processes, steps, and important molecules in aerobic respiration using an illustration. The lesson aims to help students understand and appreciate the importance of aerobic respiration for animals and plants.
Cellular respiration involves three main stages to break down glucose and produce ATP as energy. [1] Glycolysis converts glucose to pyruvate in the cytoplasm, producing a small amount of ATP. [2] The pyruvate then enters the mitochondrion, where the citric acid cycle further oxidizes it and produces more ATP and electron carriers. [3] Finally, the electron transport chain uses these carriers to pump protons across a membrane and produce a large amount of ATP through chemiosmosis. Overall, the process fully oxidizes one glucose molecule into 6 carbon dioxide molecules and produces 38 ATP.
Cellular respiration is a catabolic process that uses oxygen to break down glucose and other organic molecules to extract energy in the form of ATP. It occurs in four main stages: 1) glycolysis in the cytosol, 2) transport of pyruvate into the mitochondria, 3) the Krebs cycle in the mitochondrial matrix, and 4) the electron transport chain and oxidative phosphorylation on the inner mitochondrial membrane. The overall process produces 38 ATP molecules from complete oxidation of one glucose molecule.
1) The document provides a lesson on cellular respiration that uses simulations to explore the pathways of glycolysis, the Krebs cycle, and the electron transport chain.
2) Students will learn about the key molecules and enzymes involved in each pathway, how they extract energy from glucose, and the relative energetic content of molecules like ATP.
3) The lesson assesses student understanding with embedded questions and is designed to be used with TI-Nspire technology for interactive simulations and monitoring of student progress.
Cellular respiration is the process that releases energy from glucose in the presence of oxygen. It involves three main stages: glycolysis, the Krebs cycle, and the electron transport chain. Glycolysis breaks down glucose and produces a small amount of ATP. The Krebs cycle further breaks down the products of glycolysis and produces more ATP and electron carriers. During the electron transport chain, electrons are passed along a chain which pumps hydrogen ions across a membrane. This creates a proton gradient that is used by ATP synthase to produce large amounts of ATP from ADP and phosphate. The overall equation is that glucose and oxygen are broken down to produce carbon dioxide, water, and a large amount of ATP as energy.
The document discusses several topics related to population biology and human population growth, including:
1) Factors that influence population growth such as birth rates, death rates, and environmental limits. Populations exhibit either rapid exponential growth or slow steady growth depending on these factors.
2) Techniques scientists use to estimate population sizes such as sampling and mark-recapture when it is difficult to count all individuals.
3) Human population growth has increased rapidly over the past 150 years from 1 billion to over 7 billion currently due to declining death rates from improvements in health, education, and sanitation.
This document defines and describes different biomes, including terrestrial biomes like tundra, taiga, desert, grassland, temperate forest, and tropical rainforest as well as aquatic biomes like marine environments with photic and aphotic zones, estuaries, and freshwater biomes. It provides details on characteristic climate, plants, soils, and common animal species for each biome.
Cell cycle reproduction lecture with turning pointtas11244
Prokaryotes like bacteria reproduce through binary fission, where the cell duplicates its DNA and other components and then divides into two daughter cells. Eukaryotes undergo the cell cycle of interphase and mitosis, where interphase involves cell growth and DNA replication, followed by mitosis where the cell divides through the stages of prophase, metaphase, anaphase and telophase resulting in two identical daughter cells.
Photosynthesis is the process by which plants, algae and some bacteria use sunlight, water and carbon dioxide to produce oxygen and energy in the form of glucose. It takes place in two stages: the light-dependent reactions that use energy from sunlight to make ATP and NADPH, and the light-independent reactions known as the Calvin cycle that use ATP and NADPH to produce glucose from carbon dioxide. Chlorophyll, located in chloroplasts, absorbs sunlight and drives the light-dependent reactions that split water to produce oxygen, protons and electrons. The electrons are used to produce ATP and NADPH, which are then used in the Calvin cycle to reduce carbon dioxide to glucose.
The document describes a lesson plan activity where students act out the steps of cellular respiration. In the activity, students move between three tables representing the cytosol and mitochondria. At each table, they break down a glucose molecule and track the production of ATP, NADH, FADH2, carbon dioxide, and hydrogen ions. The goal is for students to demonstrate their understanding of aerobic respiration and how glucose and oxygen are used to produce ATP through glycolysis, the Krebs cycle, and the electron transport chain.
Meiosis gamete production with turning pointtas11244
Meiosis is a type of cell division that produces gametes, such as sperm or egg cells, with half the number of chromosomes. It involves two cell divisions: Meiosis I and Meiosis II. In Meiosis I, homologous chromosomes pair and may exchange genetic material through crossing over. The homologous chromosomes then separate, reducing the chromosome number by half. Meiosis II then separates the sister chromatids, resulting in four haploid daughter cells each with a single set of chromosomes.
The cell membrane controls what enters and exits the cell to maintain homeostasis. It is a selectively permeable bilayer made of phospholipids and embedded proteins. Small hydrophobic molecules and gases can pass through by diffusion down their concentration gradients, but most ions and larger molecules require transport proteins. Active transport uses ATP to move substances against their concentration gradients, such as the sodium-potassium pump. Endocytosis and exocytosis allow cells to ingest and secrete larger particles and molecules.
The document discusses cellular respiration, which is the process by which cells break down food molecules to produce energy in the form of ATP. It describes the three main stages of cellular respiration: glycolysis, the citric acid cycle, and the electron transport chain. Glycolysis breaks down glucose and occurs in the cytoplasm, producing a small amount of ATP. The citric acid cycle further breaks down molecules in the mitochondria, producing more ATP and electrons. The electron transport chain uses these electrons and oxygen to produce the most ATP through oxidative phosphorylation. Aerobic respiration requires oxygen while anaerobic respiration occurs without oxygen through fermentation.
1. This document describes experiments to study the effect of pH on the rate of fermentation in yeast. Students will set up solutions with yeast in buffers of varying pH and measure the amount of carbon dioxide produced over time.
2. The results will be recorded and two graphs will be made: one showing gas production over time for each pH, the other showing gas produced at 40 minutes for each pH. This will help determine the effect of pH on the rate of fermentation.
3. The effect of pH and possible mechanisms will be discussed, drawing on cell biology and metabolic knowledge.
This document summarizes the history and process of photosynthesis. It describes key discoveries such as Priestley observing that plants give off oxygen, and van Niel determining the reaction equation for photosynthesis in purple bacteria. It then explains the light and dark reactions of photosynthesis in detail, including Calvin's discovery of the Calvin cycle where carbon dioxide is incorporated into carbohydrates. The document also discusses different types of plants, including C3, C4, and CAM plants, and how they regulate photosynthesis through pathways like the Hatch-Slack cycle.
ATP, Photosynthesis, and Cellular Respirationlkocian
This document discusses energy flow through photosynthesis and cellular respiration. It begins by defining energy and the different forms it can take, including chemical energy stored in ATP. Photosynthesis uses light energy to convert carbon dioxide and water into glucose and oxygen through two reactions - the light-dependent reaction where ATP is produced, and the Calvin cycle where glucose is formed. Cellular respiration breaks down glucose and uses oxygen to release the energy stored in ATP through three stages - glycolysis, the Krebs cycle in the mitochondria, and the electron transport chain where a large amount of ATP is generated to store energy from food.
This document provides information about Module 5 of an alternative secondary education biology course on cellular respiration. The module contains 5 lessons that discuss how living organisms harvest energy stored in foods through cellular respiration. Key points covered include:
- Cellular respiration is the process where stored chemical energy in foods is converted to ATP in organisms.
- The mitochondria are where cellular respiration occurs in eukaryotic cells. They have inner and outer membranes with cristae infoldings containing protein complexes.
- Glycolysis is the first step where glucose is broken down, producing some ATP and NADH.
- An activity demonstrates how yeast cells respire and produce carbon dioxide from sugar, showing cellular respiration.
Cellular respiration occurs in three main stages to harvest energy from glucose and produce ATP. Stage 1 is glycolysis in the cytoplasm, which oxidizes glucose to pyruvate and generates 2 ATP and 2 NADH. Stage 2 is the citric acid cycle in the mitochondria, which completes glucose oxidation and generates more NADH and FADH2. Stage 3 is oxidative phosphorylation in the inner mitochondrial membrane, where electrons are transferred through an electron transport chain to generate ATP through chemiosmosis. Fermentation enables some ATP production without oxygen through glycolysis alone.
Cellular respiration involves the breakdown of glucose and other organic molecules to extract energy in the form of ATP. It occurs in three main stages: glycolysis, the Krebs cycle in the mitochondria, and oxidative phosphorylation along the electron transport chain. During aerobic respiration, glucose breakdown yields about 38 ATP molecules total. Without oxygen, anaerobic respiration produces less ATP but allows glycolysis to continue by converting pyruvate into other waste products like lactic acid.
Photosynthesis is the process by which plants, algae, and some bacteria use sunlight, water, and carbon dioxide to produce oxygen and energy in the form of glucose. It takes place in chloroplasts, which contain chlorophyll and other photosynthetic pigments. The light-dependent stage uses energy from sunlight to produce ATP and NADPH through photophosphorylation. The light-independent stage, also called the Calvin cycle, uses ATP and NADPH to fix carbon from carbon dioxide into organic molecules like glucose. Photosynthesis provides a critical energy source and oxygen for living organisms.
Photosynthesis occurs in chloroplasts within plant cells. Light energy is absorbed by chlorophyll and other pigments in the thylakoid membranes and used to convert water and carbon dioxide into oxygen and energy-rich glucose. The light reactions use photosystems to produce ATP and NADPH from water, while the Calvin cycle fixes carbon into glucose using these products in the stroma.
Photosynthesis occurs in chloroplasts and involves two phases - the light-dependent and light-independent reactions. The light-dependent reactions use energy from light to convert water to oxygen and produce ATP and NADPH. This occurs through the absorption of light by photosystems in the thylakoid membranes which creates a proton gradient, driving ATP synthase to produce ATP. The light-independent reactions then use ATP and NADPH to fix carbon from CO2 into glucose.
Chloroplasts are organelles found in plant cells and other eukaryotic cells that are the site of photosynthesis. They contain chlorophyll and have a double membrane structure, with stacks of internal membranes called thylakoids that are the site of the light-dependent reactions of photosynthesis. During photosynthesis, chloroplasts capture energy from sunlight and use it to convert carbon dioxide and water into oxygen and energy-rich molecules like glucose through a two-stage process of light-dependent and light-independent reactions.
mechanism of photosysthesis PPT, SSC AP srinivas nallapuSrinivas Nallapu
Photosynthesis uses light energy from the sun to convert carbon dioxide and water into oxygen and energy-rich organic compounds, especially glucose. This process involves two stages: the light-dependent reactions where ATP and NADPH are produced, and the light-independent reactions (Calvin cycle) where carbon is incorporated into organic compounds. The light reactions occur in the thylakoid membranes of the chloroplast and use chlorophyll to drive the production of ATP and NADPH. These products are then used in the Calvin cycle to reduce carbon dioxide into glucose.
Photosynthesis has two phases: the light-dependent reaction and the light-independent reaction. In the light-dependent reaction, chlorophyll uses energy from sunlight to split water molecules and produce oxygen, ATP, and NADPH. These products are then used in the light-independent Calvin-Benson cycle to convert carbon dioxide into glucose using ATP and NADPH as an energy source. The oxygen, glucose, and regeneration of ATP/NADPH are essential for sustaining life.
Photosynthesis is the process by which plants use carbon dioxide, water, and sunlight to produce glucose and oxygen. It involves two stages: the light-dependent reactions where ATP and NADPH are produced, and the light-independent reactions of the Calvin cycle where glucose is produced from carbon dioxide using ATP and NADPH. The light reactions take place in the thylakoid membranes of chloroplasts and use energy from sunlight to drive the synthesis of ATP and NADPH via photophosphorylation.
1. Photosynthesis uses energy from sunlight, water, and carbon dioxide to produce oxygen and energy-rich organic compounds like glucose.
2. It occurs in two phases - the light-dependent reaction uses sunlight to produce ATP and NADPH, while the light-independent Calvin-Benson cycle uses these products to incorporate carbon from CO2 into sugars like glucose.
3. The rate of photosynthesis is affected by light intensity, carbon dioxide levels, and temperature, with an optimal temperature range for plant growth. Alternative pathways allow some plants to adapt to different climates.
This document provides an overview of photosynthesis, including:
- The two pathways of photosynthesis (light reactions and Calvin cycle) that convert solar energy to chemical energy.
- The structure and function of chloroplasts, where the light reactions take place in the thylakoid membranes and the Calvin cycle occurs in the stroma.
- The light-dependent reactions that use photon energy to produce ATP and NADPH via photosystems and electron transport chains, and the light-independent Calvin cycle that fixes carbon into glucose using ATP and NADPH.
1. Photosynthesis is the process by which plants use sunlight, carbon dioxide and water to produce oxygen and energy in the form of glucose.
2. Early experiments by Priestley and Ingenhousz showed that plants release oxygen and restore air contaminated by animals, with Ingenhousz showing sunlight is required.
3. Later experiments determined the sites of photosynthesis within plants (chloroplasts and leaves), identified pigments like chlorophyll, and established the basic chemical equation of photosynthesis involving carbon dioxide, water, oxygen and glucose.
Photosynthesis is the process by which plants, algae, and some bacteria use sunlight, water and carbon dioxide to produce oxygen and energy in the form of ATP and NADPH. It occurs in two stages - the light-dependent reactions where energy from sunlight is captured and converted to chemical energy in ATP and NADPH, and the light-independent reactions where carbon dioxide is incorporated into organic compounds like glucose. There are different pathways for photosynthesis including C3, C4 and CAM which have evolved strategies to prevent the wasteful process of photorespiration.
The document summarizes photosynthesis, including:
1) Photosynthesis uses light energy, water, carbon dioxide to produce glucose and oxygen through two phases - the light reactions and dark reactions.
2) The light reactions use light to produce ATP and NADPH using chlorophyll and a series of electron carriers in the thylakoid membranes.
3) The dark reactions use ATP and NADPH to fix carbon from carbon dioxide into glucose through the Calvin cycle in the chloroplast stroma.
- Photosynthesis is the process by which plants use sunlight, water and carbon dioxide to produce oxygen and energy in the form of glucose.
- Early experiments by Joseph Priestley and Julius von Sachs helped reveal that plants restore oxygen to the air that animals remove and that glucose is produced through a process involving sunlight, chlorophyll and carbon dioxide.
- Photosynthesis takes place in the chloroplasts of plant leaves. The light reactions use energy from sunlight to produce ATP and NADPH, while the carbon reactions use these products to fix carbon and produce sugars like glucose.
1. The documents discuss photosynthesis, explaining that it is the process by which plants use sunlight, carbon dioxide, and water to produce glucose and oxygen.
2. It describes the light reactions and Calvin cycle, noting that the light reactions produce ATP and NADPH using energy from sunlight which is then used in the Calvin cycle to produce glucose from carbon dioxide.
3. The documents focus on explaining why plants appear green, noting that chlorophyll a absorbs mostly blue and red light while reflecting green light, making plants appear green.
1. The documents discuss photosynthesis, explaining that it is the process by which plants use sunlight, carbon dioxide, and water to produce glucose and oxygen.
2. It describes the light reactions and Calvin cycle, noting that the light reactions produce ATP and NADPH using energy from sunlight which is then used to fix carbon in the Calvin cycle.
3. The documents focus on explaining why plants are green, noting that chlorophyll a absorbs mostly blue and red light while reflecting green light, making plants appear green.
This presentation summarizes key aspects of photosynthesis, including:
1) Autotrophs like plants use photosynthesis to produce oxygen and energy-rich molecules like glucose from carbon dioxide, water, and sunlight.
2) Photosynthesis occurs in leaves through the light-dependent reactions that capture solar energy and produce ATP and NADPH, and the light-independent Calvin cycle that uses these products to fix carbon from carbon dioxide into organic molecules.
3) The structure of leaves and chloroplasts facilitates photosynthesis through specialized tissues, membranes, and pigments that absorb sunlight and drive the light reactions.
The document outlines the key processes and components of photosynthesis. It discusses how chloroplasts use light energy from the sun to transform carbon dioxide and water into oxygen and energy-rich glucose through two stages - the light-dependent reactions which generate ATP and NADPH, and the light-independent Calvin cycle which uses these products to fix carbon into sugars. Chlorophylls and other pigments play a crucial role in absorbing sunlight for photosynthesis, which is why plants appear green.
Photosynthesis PPT FOR CLASS 9,10 and 11Th studentsKumarlalit750
The document outlines the key processes and components of photosynthesis. It discusses how chloroplasts use light energy harvested by pigments like chlorophyll to drive photophosphorylation, producing ATP and NADPH through electron transport chains. The Calvin cycle then uses these products to fix carbon from CO2 into sugars, providing the basic energy currency and building blocks for life. Plants appear green because chlorophyll predominantly absorbs wavelengths other than green.
Photosynthesis is the process by which plants, algae, and some bacteria use sunlight, water and carbon dioxide to produce oxygen and energy in the form of glucose. It occurs in chloroplasts through two stages - the light reactions where sunlight is absorbed to make ATP and NADPH, and the Calvin cycle where carbon dioxide is fixed using these products to make glucose. Chloroplasts contain chlorophyll and other pigments which absorb light and drive the transfer of electrons to generate a proton gradient and ultimately ATP through chemiosmosis. Oxygen is released as a byproduct of splitting water during the light reactions.
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This document provides an Ohm's Law worksheet with 6 practice problems calculating voltage, current, and resistance using the equations: I = V/R, R = V/I, and V = IR. Students are asked to use these equations to find the missing value in each circuit scenario, such as calculating the voltage applied to a light bulb with a known current and resistance.
This document discusses resistance and Ohm's Law. It describes the key parts of Ohm's Law including volts, amps, and resistance. It also explains how to calculate an unknown value using two known values and Ohm's Law. Examples are provided to demonstrate calculating current and resistance using Ohm's Law. The document also discusses how resistance affects current and electric shock, and provides examples of calculating current through the body at different resistances and voltages.
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1. CHAPTER 10-Photosynthesis
• Life on Earth is solar powered
• Photosynthesis nourishes almost all the living world directly or indirectly
° All organisms use organic compounds for energy and for carbon skeletons.
° Organisms obtain organic compounds by one of two major modes: autotrophic or heterotrophic
AUTOTROPHS (=producers)
• produce organic molecules from CO2 and other inorganic raw materials obtained from the environment
• ultimate source of organic compounds for heterotrophs
Photoautotrophs use light as a source of energy to synthesize organic compounds.
• Photosynthesis occurs in plants, algae, some other protists, and some prokaryotes.
Chemoautotrophs
• harvest energy from oxidizing inorganic substances, such as sulfur and ammonia
• unique to prokaryotes
HETEROTROPHS (=consumers)
• live on organic compounds produced by other organisms
• dependent on photoautotrophs for food and for oxygen (by-product of photosynthesis)
PHOTOSYNTHESIS:
• converts light energy to the chemical energy of food
6CO2 + 6H2O + light energy ◊ C6H12O6 + 6O2
• Happens in all green parts of plants but leaves = major site
~ about half a million chloroplasts/mm2 of leaf surface
• Color of leaf due to green pigment chlorophyll
Chloroplasts mainly in mesophyll cells in the interior of the leaf
30–40 chloroplasts/typical mesophyll cell
O2 and water vapor exits and CO2 enters leaf through microscopic
pores on underside of leaf = stoma (pl. stomata)
GUARD CELLS control openings- OPEN if TURGID; CLOSED if FLACCID
VEINS bring water from the roots and carry off sugar from mesophyll cells to nonphotosynthetic areas of plant
XYLEM-carries water/PHLOEM carries sugar/nutrients
CHLOROPLAST:
• Surrounded by DOUBLE membrane
• Central fluid filled space = STROMA
• System of interconnected membranous sacs = THYLAKOIDS
• Stack of thylakoids = GRANUM (pl. GRANA)
• Fluid filled compartment inside thylakoid
=THYLAKOID SPACE (lumen)
• Chlorophyll is located in membranes of thylakoid sacs
Photosynthetic prokaryotes lack chloroplasts
- photosynthetic membranes = infolded regions of the plasma membrane
LIGHT
= form of electromagnetic radiation
Energy = inversely related to its wavelength
(ie, shorter wavelengths pack more energy)
Visible light = 380-750 nm
2. PIGMENTS = light absorbing molecules
• Only chlorophyll a participates directly in the light
reactions;
• Other pigments have different absorption spectra;
funnel energy to chlorophyll a
Chlorophyll a (the dominant pigment)
• ABSORBS best in the red & violet-blue wavelengths;
• REFLECTS green wavelengths = reason plants “look”
green
Chlorophyll b- slightly different structure
• funnels energy to chlorophyll a
CAROTENOIDS = accessory pigments (red, yellow,
orange);
• Include: CAROTENES (orange) and XANTHOPHYLLS
(yellow)
• funnel the energy to chlorophyll a
• photoprotection- protect chlorophyll from excessive light
CHLOROPHYLL
Porphorin ring with MAGNESIUM cofactor in center
Plants have a and b forms- slight difference in functional groups
Chlorophyll a is universal
Other forms found in algae and cyanobacteria
SPECTROPHOTOMETER
•measures the ability of pigment to absorb various wavelengths of light
•beams narrow wavelengths of light through a solution containing the pigment
•measures the fraction of light transmitted at each wavelength
•Absorption spectrum plots a pigment’s light absorption versus wavelength.
EXCITING ELECTRONS:
When a molecule absorbs a photon of light an electron is elevated to an orbital with more potential energy
Electron moves from ground state → excited state
Excited electrons are unstable
They drop to their ground state in a billionth of a second, releasing heat energy
Some pigments, including chlorophyll, can also release a photon of light when excited (= FLUORESCENCE)
Outside of chloroplasts, if chlorophyll is illuminated, it will fluoresce and give off heat
PHOTOSYSTEMS in thylakoid membranes
• reaction center containing chlorophyll a and “primary electron acceptor”
• surrounded by a light-harvesting complex of other pigments and proteins (chlorophyll b, carotenoids)
• act as “antenna” to collect light energy → chlorophyll a → “primary electron acceptor”
Photosystem I (PS I) reaction center absorption peak at 700 nm (P700)
Photosystem II (PS II) reaction center absorption peak at 680 nm (P680)
TWO STAGES OF PHOTOSYNTHESIS:
1) LIGHT REACTIONS (Light dependent reactions)
convert solar energy to the chemical energy of ATP and NADPH
2) CALVIN CYCLE (Light independent reactions)
uses energy from the light reactions to incorporate CO2 from the atmosphere into sugar.
3. Named for Melvin Calvin (Got Nobel in 1961 for figuring out pathway)
LIGHT REACTIONS:
• Use solar power to store chemical energy in ATP and reducing power in electron carrier NADPH
• REQUIRE sunlight
•Two possible routes
1) NONCYCLIC ELECTRON FLOW (= predominant route) produces both ATP and NADPH
- Photosystem II absorbs a photon of light
- One of the electrons of P680 reaction center is excited to a higher energy state
- Electron is captured by the primary electron acceptor, leaving the reaction center oxidized
- Electrons are replaced by splitting a water molecule in thylakoid space
- Oxygen released from water splitting combines with another oxygen atom; released as O2 to atmosphere
- Hydrogen released from water splitting accumulates in thylakoid space
- Photoexcited electrons pass along electron transport chain ending up at Photosystem I reaction center
- energy from electrons “falling down” ETC is used by CYTOCHROMES to pump H+ ions into thylakoid space
• When chloroplasts are illuminated, thylakoid space pH ~5; stroma pH ~ 8 (1000 fold difference)
- Photosystem I absorbs a photon of light
- One of the electrons of P700 reaction center is excited to a higher energy state
- Electron is captured by the primary electron acceptor, leaving the reaction center oxidized
- Electrons are replaced by electrons passed from PS II down ETC
- Photoexcited electrons pass down a second electron transport chain through the protein FERRIDOXIN
(Fd)
- Enzyme transfers 2 electrons to NADP+ (nicotinamide adenine dinucleotide phosphate) to produce
NADPH
- H+ ions in thylakoid space provide energy to produce ATP as they diffuse down
their gradient (ELECTROMOTIVE FORCE) back into the stroma through ATP SYNTHASE
2) CYCLIC ELECTRON FLOW
• alternative pathway for photoexcited electrons from photosystem I = CYCLIC PHOTOPHOSPHORYLATION
• Photoexcited electrons return to CYTOCHROMES instead of passing to Ferridoxin
• So produces only ATP; NO NADPH; no OXYGEN
4. • Used because NON CYCLIC FLOW makes equal amounts of ATP and NADPH
• Calvin cycle requires more ATP than NADPH
• Way to regulate amounts of ATP and NADPH needed for Calvin cycle
CHEMIOSMOSIS IN CHLOROPLASTS AND MITOCHONDRIA
SIMILARITIES
• Used by chloroplasts and mitochondria to generate ATP
• Energy from ELECTRON TRANSPORT CHAIN used to pump protons across a membrane
• Creates a H+ gradient across membrane
•ATP SYNTHASE uses energy from diffusion of H+ ions back across membrane to generate ATP
• Some electron carriers (cytochromes) are similar in both chloroplasts/mitochondria
DIFFERENCES:
OXIDATIVE PHOSPHORYLATION in MITOCHONDRIA
• Mitochondria transfer chemical energy from food molecules to ATP
• Mitochondrial INNER MEMBRANE pumps protons from MATRIX out to the INTERMEMBRANE SPACE
• ATP made as H+ ions diffuse back to stroma
PHOTOPHOSPHORYLATION in CHLOROPLASTS
• Chloroplasts transform light energy into the chemical energy of ATP
• Chloroplast THYLAKOID membrane pumps protons from the stroma into the thylakoid space
CALVIN CYCLE (= LIGHT INDEPENDENT PHASE)
Originally called “Dark reactions” but don’t just happen at night
Happens in stroma
Uses ATP and NADPH (made in Light Reactions) to convert CO 2 to sugar
regenerates its starting material after molecules enter and leave the cycle
= anabolic -uses energy to build sugar from smaller molecules
Carbon enters the cycle as CO2 and leaves as sugar
Actual sugar product = three-carbon sugar, glyceraldehyde-3-phosphate (G3P)
Each turn of the Calvin cycle fixes carbon from 1 CO2; 3 turns to make 1 G3P; 6 turns to make 1 glucose
Uses 18 ATP’s and 12 NADPH’s to make 1 glucose
5. CALVIN CYCLE
Phase 1: Carbon fixation
Each CO2 molecule is attached to a five-carbon sugar, RIBULOSE BISPHOSPHATE (RuBP)
° This is catalyzed by RuBP carboxylase (=RUBISCO)
° Rubisco = most abundant protein in chloroplasts; probably the most abundant protein on Earth
° Unstable six-carbon intermediate splits in half to form two three carbon 3-phosphoglycerate for each CO 2
Phase 2: Reduction
ATP provides energy; NADPH provides reducing power to reduce intermediates
Three carbon GLYCERALDEHYDE-3-PHOSPHATE (G3P) is produced
G3P exits the cycle; = starting material for metabolic pathways that synthesize other organic compounds,
including glucose and other carbohydrates
Phase 3: Regeneration
Rest of molecules rearrange to regenerate the starting RuBP molecules
For the net synthesis of one G3P molecule, the Calvin cycle consumes nine ATP and six NADPH (X 2 for glucose)
Light reactions regenerate ATP and NADPH
WHERE DOES THE OXYGEN IN SUGAR COME FROM: H2O or CO2?
CO2 + H2O + light energy ◊ [CH2O] + O2
[CH2O] represents the general formula for a sugar
Before 1930’s thought splitting H2O provided oxygen for sugar
Experiments with radio-labeled oxygen isotopes in H2O and CO2 showed oxygen in carbo’s comes from CO 2
Evidence that chloroplasts split water molecules enabled researchers to track atoms through photosynthesis.
Powered by light, the green parts of plants produce organic compounds and O2 from CO2 and H2O
Photosynthesis is a REDOX REACTION
° It reverses the direction of electron flow in cellular respiration
° H2O is OXIDIZED (loses electrons)
° CO2 is REDUCED (gains electrons) to make sugar
° Process requires energy (provided by light)
OIL RIG
C3 PLANTS = Most plants (EX: rice, wheat, and soybeans) Oxidation Is Losing
Rubisco fixes CO2 into three carbon compound (3PGA)
Reduction Is Gaining
Calvin cycle happens during day when ATP and NADPH are available
from light reactions
PROBLEM: Closing stomata on hot dry days to conserve water,
reduces CO2 needed for photosynthesis
When CO2 is low Rubisco adds O2 to RuBP instead of CO2
= PHOTORESPIRATION
Rubisco adds O2 to RuBP, RuBP splits into a three-carbon piece and a two-carbon piece
Two-carbon fragment is exported from chloroplast and degraded to CO 2 by mitochondria and
peroxisomes.
° Unlike normal respiration, consumes ATP instead of making it
° Unlike photosynthesis, siphons organic material from the Calvin cycle instead of making sugar
° Photorespiration can drain away as much as 50% of the carbon fixed by the Calvin cycle on a hot, dry day.
PHOTORESPIRATION may be evolutionary baggage
When rubisco first evolved, the atmosphere had far less O 2 and more CO2 than it does today
6. Inability of the active site of rubisco to exclude O2 would have made little difference then,
BUT makes a difference today when O2 in atmosphere is higher
Alternative mechanisms of carbon fixation
Certain plant species have evolved alternate modes of carbon fixation to minimize photorespiration
C4 PLANTS- EX: sugarcane and corn
Minimizes photorespiration and allows plant to
efficiently fix CO2 at low concentrations
Allows plants to thrive in hot regions with intense
sunlight
Unique leaf anatomy; spatial separation of CO2 fixation from air/into
sugar
BUNDLE SHEATH cells arranged into tightly packed sheaths around leaf veins
MESOPHYLL cells more loosely arranged cells located between bundle
sheath cells
and leaf surface
PEP CARBOXYLASE in mesophyll cells has very high affinity for CO2 ;
Can fix CO2 efficiently at low levels when rubisco can’t
CO2 fixed into a FOUR CARBON compound/ pumped into BUNDLE SHEATH cells
CO2 is released in Bundle sheath cells, keeping CO2 levels high enough for
rubisco to work in Calvin cycle
PEP Carboxylase also found in some bacteria, but not animals or fungi.
CRASSULACEAN ACID METABOLISM (CAM) PLANTS- EX: Succulents, cacti, pineapples
Evolved in hot, dry environments
TEMPORAL separation of CO2 fixation from air/into sugar
Open stomata during night when temps are lower and humidity higher
Close them during the day to save water
AT NIGHT: Fix CO2 in mesophyll cells
Use PEP carboxylase, like C4 plants, to fix CO2 forming four carbon compounds
Stored in vacuoles
DURING DAY:
Light reactions supply ATP & NADPH;
CO2 is released from organic acids to complete Calvin cycle
IMPORTANCE OF PHOTOSYNTHESIS:
Energy from sunlight = stored as chemical energy in organic compounds
Sugar made in the chloroplasts supplies the entire plant with chemical energy
AND with carbon skeletons to synthesize all the major organic molecules of cells
- Carbohydrate (as disaccharide sucrose) travels via the veins to nonphotosynthetic cells
-About 50% = consumed as fuel for cellular respiration in plant mitochondria
Also provides raw materials for anabolic pathways, including synthesis of proteins and lipids and formation of
the extracellular polysaccharide cellulose
Cellulose = main ingredient of cell walls; = most abundant organic molecule in the plant, maybe on
Earth
Plants also store excess sugar by synthesis of starch
in chloroplasts and in storage cells in roots, tubers, seeds, and fruits.
On a global scale, photosynthesis is the most important process on Earth
° Provides food energy for heterotrophs, including humans
7. ° It is responsible for the presence of oxygen in our atmosphere.
° Each year, photosynthesis synthesizes 160 billion metric tons of carbohydrate