Light light from the sun Electric runs appliances in home Mechanical used to power a wind up toy Heat burn wood to produce fire Chemical gas to a car Table of Contents Section 1 Energy and Living Things Section 2 Photosynthesis Section 3 Cellular Respiration Energy and Living Systems comes from the sun Building Molecules That Store Energy Directly or indirectly almost all of the energy in living systems needed for metabolism Metabolism involves either using energy to build molecules or breaking down molecules in which energy is stored Photosynthesis is the process by which light energy is converted to chemical energy Organisms that use energy from sunlight or from chemical bonds in inorganic substances to make organic compounds are called autotrophs Breaking Down Food for Energy The chemical energy in organic compounds can be transferred to other organic compounds or to organisms that consume food Organisms that must get energy from food instead of directly from sunlight or inorganic substances are called Heterotrophs Cellular respiration is a metabolic process similar to burning fuel Transfer of Energy to ATP When cells break down food molecules some of the energy in the molecules is released as heat Much of the remaining energy is stored temporarily in molecules of ATP Like money ATP is a portable form of energy currency inside cells ATP delivers energy wherever energy is needed in a cell ATP Adenosine Triphosphate ATP ATP is a nucleotide with two extra energy storing phosphate groups Energy is released when the bonds that hold the phosphate groups together are The removal of a phosphate group from ATP produces adenosine diphosphate or broken ADP Photosynthesis Stage 1 How is the energy captured from the sun Stage 2 What is the function of the electron transport chain Stage 3 How does the Calvin cycle work and how does it relate to carbon dioxide fixation Stage 1 How do we see light Light absorbing substances called Pigments Primary pigment in plants is Chlorophyll absorbs red and blue reflects green and yellow Carotenoids these are pigments that produce yellow and orange Production of Oxygen Clusters of pigments embedded in the membranes Thylakoids When light strikes the Thylakoids energy is transferred to electrons in chlorophyll This energy transfer causes the electrons to Jump to a higher level Electron Transport chain Provides energy used to make ATP and a 2nd change is Stage 2 conversion of light energy used to make NADPH ATP and NADPH are chemical energy Stage 3 Carbon Fixation the Calvin Cycle Glucose Sugar Cellulose Plant structure Starch Sugar stored Step 1 CO fixation Step 2 6 to 3 carbon compounds Glucose C H O Step 3 1 carbon molecule is used to make sugar Step 4 remaining three carbons are used to start the cycle all over again Summary of Photosynthesis Pigment molecules in the thylakoid of chloroplasts absorb light energy The electrons in the pigments are excited by light and move through the electron transport chain in the thylakoid membranes Those electrons are replaced by the electrons from H O molecules combine to form O Hydrogen H accumulate inside thylakoids setting up a concentration gradient that provides energy to make ATP The calvin cycle makes use of ATP for survival Cellular Respiration Equation for Cellular Respiration Glucose Oxygen CO Water Energy Source of Energy ATP