Ecosystem Energy Transfer - PDF

# CHAPTER 1 ## LESSON 1 ### Transfer of ecosystem energy ### Introduction * In this lesson we will… * Explore how energy from the sun is transmitted through ecosystems through food chains * How does energy transition affect the ecological balance ### FIRST: * The concept of energy in...

# CHAPTER 1 ## LESSON 1 ### Transfer of ecosystem energy ### Introduction * In this lesson we will… * Explore how energy from the sun is transmitted through ecosystems through food chains * How does energy transition affect the ecological balance ### FIRST: * The concept of energy in the ecosystem * One way to study the interaction between living organisms in ecosystems is to track the transfer of energy through this system ### So how the energy transfer through the system? * Green plants receive sunlight and perform photosynthesis. * 6CO2 + 6H2O → C6H12O6 + 6O2 * Plant is eaten by insect. It obtains a chemical energy that is stored in the plants. * Insect is eaten by animal. The energy is transferred from the insect to the animal ### Integrated science secrets ### Secondary one ## CHAPTER 1 ### Note * As energy moves from one trophic level to another, a large amount is lost. * These transformations continue until the energy reaches the decomposer organisms, which return the remaining chemical energy from the dead organisms to the soil in the form of salts. * Notice that the energy pyramid rarely contains 6 levels as the remaining energy becomes insufficient to sustain another organism. ### Energy Flow In Ecosystem * Producers * Plants * autotrophic organisms * Primary Consumers * herbivores * heterotrophic organisms * Secondary Consumers * carnivores * heterotrophic organisms * Energy loss simply the energy not used directly, representing the difference between the total energy from food and the energy utilized by the organism for essential processes such as movement and growth. ### Trophic levels ### Measurement and transfer of energy * It states that the energy transferred from one level to another is equal to 10% of the stored energy. So, throughout the food chain a portion of energy is lost at each level. * In vital processes such as: cellular respiration, stored energy (glucose) is consumed to produce the energy needed to perform vital functions. * 90% of ENERGY LOST causes of energy loss ### Calculation of wasted energy * The expression «lost energy» does not contradict the law of conservation of energy. * Law of conservation of energy: energy can neither be created nor be destroyed. Although, it may be transformed from one form to another. * Where a large part of the energy is lost in the form of heat during the vital systems. * So it is better for humans to get their food from plants, as they provide them with the greatest amount of energy that they get from animals ### Integrated science secrets ### Secondary one ## CHAPTER 1 ### Example * An example that illustrates how energy is transferred within an organism’s body * A rabbit eats a plant and gets 100 joules stored in its food ### CALCULATION OF WASTED ENERGY * **During cellular respiration** * The majority of energy is converted in the process of burning sugar during cellular respiration to CO2. * This is chemical energy and is released into nature during exhalation. * **Thermal energy** * Another part of the energy is converted into heat to warm the body and maintain its temperature. * The total will be 100J. * This is aligns with the law of conservation of energy. * **Kinetic energy** * A part of the energy is produced that is used in the rabbit's movement. * **Undigested food** * There a part of the energy is stored in the undigested food and exits the body in the form of waste (chemical energy) ### LAW OF CONSERVATION OF ENERGY IN FOOD CHAINS 1. Law of conservation of energy is demonstrated in food chains through transformation of energy into various forms. The chain begins with solar energy from the sun, which is converted within plants into chemical energy stored in food during the process of photosynthesis. 2. Then, energy is transferred to the primary consumer when it feeds on the plant. During this stage, the chemical energy undergoes conversion into thermal and kinetic energy through respiration, with some energy lost as heat. 3. When energy is transferred to the secondary consumer, which feeds on the primary consumer, additional energy loss occurs during processes such as respiration and excretion. 4. These energy transformations continue until the remaining chemical energy in the decomposed organisms is recycled into the soil by decomposers in the form of nutrients. 5. Throughout the food chain, energy is lost at each level in the form of heat. However, this does not contradict the law of conservation of energy, which states that energy cannot be created or destroyed but only transformed from one form to another. ### Integrated science secrets ### Secondary one ## CHAPTER 1 ### Chemistry in energy transfer * The energy journey begins inside living organisms with green plants where they carry out the process of photosynthesis. * Photosynthesis occurs inside chloroplasts. ### Photosynthesis Mechanism * **Chemical reactions:** light absorbed by chlorophyll (A green pigment ) stimulates complex chemical reactions. * CO2 and H2O converts to oxygen and glucose (chemical energy stored in it) * 6CO2 + 6H2O → C6H12O6 + 6O2 ( Glucose + Oxygen ) * This energy transferred to animals that feeds on the plant. ### Process of cellular respiration * When the glucose is burning by using oxygen, it relaese heat energy that responsible for the life of living organisms. * C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy ### SOURCE OF ENERGY IN FOSSIL FUELS * The energy stored in fossil fuels (coal, oil, natural gas) originally comes from solar energy by direct or indirect way. ### Composition of fossil fuels * **Petroleum:** It is a mixture of hydrocarbon compounds. * It originated from marine organisms and marine plants that were buried for millions of years ago. * They were exposed to high pressure and heat which led to their decomposition and the formation of petroleum. ### Coal: * It consists mainly of carbon (C). * It originated from the decomposition of trees and plants that were buried under the layers of the earth millions of years ago. ### Notice that * And by that we conclude that Light energy convert to chemical energy stored between the chemical bonds in glucose molecule, then thermal energy that responsible for the life of living organism ### Integrated science secrets ### Secondary one ## CHAPTER 1 * **Natural gas:** It consists of hydrocarbon gases, such as: * Methane (CH4): the largest proportion (70-98%). * Ethane (C2H6), propane (C3H8), butane (C4H10): in smaller proportions. * **Natural gas exists in two states:** * Floating on oil In its underground locations. * In mines or between rocks. ### Utilization of Fossile fuels * When fossil fuels are burned with oxygen, The stored chemical energy is released as heat energy, which is used to operate machines, such as: * Car engines. * Turbines in power plants. ### The relation between photosynthesis and cellular respiration * **The photosynthesis:** Plants during the process * Carbon dioxide (CO2) is absorbed from the atmosphere and energy stored in glucose molecule * Oxygen (O2) is released. * **Cellular respiration** * In living organisms (humans, animals). * Glucose (from photosynthesis) and oxygen are used to produce energy. * As a result, carbon dioxide and water are released as waste products ### The importance of these process * These reactions contribute to maintaining the balance of oxygen and carbon dioxide in the atmosphere ### Integrated science secrets ### Secondary one ## CHAPTER 1 ### Impact of This Relationship on the Ecosystem * **Environmental Balance:** * Photosynthesis produces oxygen, which is essential for respiration in living organisms. * In return, respiration releases carbon dioxide, which plants need for photosynthesis. * This cycle maintains the balance of gases (oxygen and carbon dioxide ) in the atmosphere. * **Energy Flow:** * Solar energy stored in glucose during photosynthesis is transferred through food chains, starting with plants consumed by animals. * Animals digest glucose and use it in cellular respiration to produce ATP, the main energy source for their biological processes. * **The Carbon Cycle:** * The natural carbon cycle is a continuous process where carbon dioxide and water is recycled between the environment and living organisms, ensuring life sustains on Earth. * Photosynthesis and cellular respiration are central to this cycle. * The process of photosynthesis provides oxygen and glucose, which is used in the process of cellular respiration to release energy ### Lesson 1 Is Over ### Integrated science secrets ### Secondary one