Photosynthesis and Cellular Respiration PDF

PHOTOSYNTHESIS  Objectives: 1. functionally define photosynthesis and cellular respiration; 2. identify the reactants and products of photosynthesis and cellular respiration;  Objectives: 3. compare the chemical compounds that make up the reactants and products of photosynthesi...

PHOTOSYNTHESIS  Objectives: 1. functionally define photosynthesis and cellular respiration; 2. identify the reactants and products of photosynthesis and cellular respiration;  Objectives: 3. compare the chemical compounds that make up the reactants and products of photosynthesis and respiration;  Objectives: 4. interpret a diagram to explain how oxygen and carbon dioxide are exchanged between living things and the environment.  THINK-PAIR-SHARE What do you think would happen if plants disappear from Earth? Introduction to photosynthesis From the Greek PHOTO = produced by light SYNTHESIS = a whole made of parts put together. Additional definition: PHOTOSYNTHESIS is the process whereby plants, algae, some bacteria, use the energy of the sun to synthesize organic compounds (sugars) from inorganic compounds (CO2 and water). How do we obtain ENERGY? WHAT DOES ATP DO FOR YOU? It supplies YOU with ENERGY! HOW DO WE GET ENERGY FROM ATP? By breaking the high- energy bonds between the last two phosphates in ATP HOW DOES THIS HAPPEN? An Enzyme! WHEN IS ATP MADE IN THE BODY? During a Process called Cellular Respiration that takes place in both Plants & Animals Tasks of ATP 1. Chemical work: ATP is used for building macromolecules. 2. Transport work: ATP is used for transporting ions membranes. 3. Mechanical work: ATP is used for mechanical processes such as muscle contraction and cilia movement. Chemical reaction is a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Reactants are substances that start a chemical reaction. (ingredients) Products are substances that are produced in the reaction. (finished results) Photosynthesis and Cellular Respiration Photosynthesis and respiration are complementary processes in the living world. Photosynthesis is the process of converting sun’s energy into chemical energy in the form of sugar and carbohydrates. Respiration is the process by which cells in plants and animals break down sugar and turn it into energy. The release of chemical energy for use by cells. What happens during photosynthesis? Plants capture light energy and use that energy to make glucose. Sunlight provides the energy needed by chlorophyll to change molecules of carbon dioxide and water into glucose. Oxygen is also released in this reaction. Carbon dioxide enters the leaf through holes called stomata CO2 combines with the stored energy in the chloroplasts through a chemical reaction to make glucose.  Chlorophyll is the pigment inside the chloroplast that absorbs light for photosynthesis are plant cell organelles that convert light energy into relatively stable chemical energy via the photosynthetic process. As the chlorophyll in leaves decays in the autumn, the green color fades and is replaced by the oranges and reds of carotenoids, other pigments. WHY IS PHOTOSYNTHESIS SO IMPORTANT? PHOTOSYNTHESIS is one of the most important biological process on earth! Provides the oxygen we breathe Consumes much of the CO2 Food Energy Fibers and materials Photosynthesis has two stages: Thylakoids Light dependent -requires photons from LIGHT -takes place in between THYLAKOIDS -uses light and water to produce OXYGEN and 2 energy carrying molecules; a. ATP (Adenosine triphosphate) – energy currency of the cell b. NADPH (Nicotinamide Adenine Dinucleotide Phosphate Hydrogen)  Stroma Photosynthesis has two stages: Light independent REACTION / CALVIN CYCLE -does not require LIGHT -takes place in STROMA -uses carbon dioxide and NADPH to produce CARBOHYDRATE or SUGAR  CARBON DIOXIDE WATER GLUCOSE OXYGEN 6 CO2 + 6H2O +ENERGY C6H12O6 + 6 O2 6 X 2 = 12 6X1=6 6 + 12 + C- 6 C- 1 (6) = 6 H- 12 H- 2 (6) = 12 O- 8 18 O- 3 18  Equation for the chemical reaction of photosynthesis EQUATION FOR PHOTOSYNTHESIS WATER OXYGEN 6CO2 + 6H2O +ENERGY C6H12O6 + 6O2 CARBON GLUCOSE DIOXIDE  CALVIN CYCLE Calvin cycle is also known as the C3 cycle. It is the cycle of chemical reactions where the carbon from the carbon cycle is fixed into sugars. It occurs in the chloroplast of the plant cell. The Calvin cycle is a process that plants and algae use to turn carbon dioxide from the air into sugar, the food autotrophs need to grow. Every living thing on Earth depends on the Calvin cycle. Plants depend on the Calvin cycle for energy and food. Cellular Respiration: Is the process of breaking down complex molecules such as SUGAR to release ENERGY in the form of ATP. Respiration occurs in ALL cells and can take place either with or without oxygen present. BREATHING VERSUS CELLULAR RESPIRATION  Breathing: physical process that allows animals and humans to come into contact with gases in the air.  Cellular respiration: chemical process that releases energy from organic compounds (food), gradually converting it into energy that is stored in ATP molecules. CHEMICAL PATHWAYS ☼ Food is the raw material that provides the energy for your body to function. ☼ Cells use food to synthesize new molecules to carry out their life processes.  Cells do not BURN glucose, they slowly release energy from it and other food compounds through several pathways (processes)  1st pathway → glycolysis: releases only a small amount of energy (2 net ATP)  If oxygen - present, it will lead to two other pathways that release a lot of energy: Krebs cycle & Electron Transport Chain.  If oxygen - absent, glycolysis is followed by a different pathway: Alcoholic Fermentation or Lactic Acid Fermentation. BUT FIRST…MITOCHONDRION STRUCTURE  Mitochondrion has two separate membranes: inner and outer membrane.  Three compartments: intermembrane space, cristae space, and matrix  Aerobic and anaerobic respiration share the glycolysis pathway. If oxygen is absent, fermentation may take place, producing lactic acid or ethyl alcohol and carbon dioxide. Products of fermentation still contain chemical energy, and are used widely to make foods and fuels. ALCOHOLIC FERMENTATION Yeast and a few other microorganisms use alcoholic fermentation, forming ethyl alcohol and carbon dioxide as wastes. LACTIC ACID FERMENTATION 1. Many cells convert accumulated pyruvic acid from glycolysis to lactic acid; lactic acid fermentation regenerates NAD+ so glycolysis can continue. 2. When your body cannot supply enough oxygen to muscle tissues during exercise, this is produced. 3. Without oxygen the body is unable to produce all the ATP it requires, so lactic acid fermentation takes over.  CELLULAR respiration -takes place in the MITOCHONDRIA; the power house of the cells Mitochondria  EQUATION FOR RESPIRATION Involves SUGAR and OXYGEN reacting to produce CARBON DIOXIDE, WATER and ENERGY in the form of ATP. CARBON GLUCOSE DIOXIDE ATP C6H12O6 + 6O2 6CO2 + 6H2O + ENERGY OXYGEN WATER PHOTOSYNTHESIS AND CELLULAR RESPIRATION Occurs in PLANTS, ALGAE and Occurs in ALL LIVING THINGS photosynthetic BACTERIA Sun’s ENERGY is converted into Sugar is broken down to release SUGAR energy in the form of ATP Takes place in the Takes place in the CHLOROPLAST MITOCHONDRIA Uses CARBON DIOXIDE and Uses SUGAR and OXYGEN to form WATER using LIGHT ENERGY to CARBON DIOXIDE, WATER and form SUGAR and OXYGEN ENERGY  objectives 1. Identify different forms of energy in their surroundings; 2. Present and explain a real-life analogy of the ATP=ADP cycle; 3. Relate the experiment done and the game to free energy and equilibrium; and ATP cycle respectively.  ATP: The Cell’s Currency Life processes require a constant supply of energy. Cells use energy that is stored in the bonds of certain organic molecules. Adenosine triphosphate (ATP) is a molecule that transfers energy from the breakdown of food molecules to cell processes.  ATP: Structure Adenosine triphosphate (ATP) is the most important biological molecule that supplies energy to the cell. A molecule of ATP is composed of three parts bonded together by “high energy” bonds: 1. A nitrogenous base (adenine) 2. A sugar (ribose) 3. Three phosphate groups (triphosphate)  ATP Adenine Ribose 3 Phosphate groups ATP C10H16N5O12P3 Where does ATP come from? ATP comes indirectly from the food that we eat. Molecules of carbohydrates (glucose) and lipids are broken down through the process of cellular respiration to produce ATP. ATP-ADP Cycle The energy stored in ATP is released when a phosphate group is removed from the molecule. ATP has three phosphate groups, but the bond holding the third phosphate groups is very easily broken. When the phosphate is removed, ATP becomes ADP— adenosine diphosphate A phosphate is released into the cytoplasm and energy is released. ADP is a lower energy molecule than ATP, but can be converted to ATP by the addition of a phosphate group. ATP → ADP + phosphate + energy available for cell processes.  Steps in the ADP-ATP Cycle To supply cells with energy, a “high energy” bond in ATP is broken. ADP is formed and a phosphate is released back into the cytoplasm. ATP ADP + phosphate + energy Steps in the ADP-ATP Cycle As the cell requires more energy, ADP becomes ATP when a free phosphate attaches to the ADP molecule. Then energy needed to create an ATP molecule is much less than the amount of energy produced when the bond is broken. ADP + phosphate + energy ATP How do you “recharge” the battery? ADP is continually converted to ATP by the addition of a phosphate during the process of cellular respiration. ATP carries much more energy than ADP. As the cell requires more energy, it uses energy from the breakdown of food molecules to attach a free phosphate group to an ADP molecule in order to make ATP. ADP + phosphate + energy from breakdown of food molecules→ ATP When is ATP used? ATP is consumed in the cell by energy-requiring processes and can be generated by energy-releasing processes. In this way ATP transfers energy between separate biochemical reactions in the cell. ATP is the main energy source for the majority of cellular functions. This includes the production of organic molecules, including DNA and, and proteins. ATP also plays a critical role in the transport of organic molecules across cell membranes, for example during exocytosis and endocytosis. Types of Reactions Exergonic (energy-yielding) – Produces ATP – Ex. Cellular respiration Endergonic (energy-requiring) reactions – Requires ATP – Ex. Photosynthesis  ATP VS ADP ATP ADP Main energy source for the cell Contains Less energy Contains 3 phosphate groups Contains 2 phosphate groups (triphosphate) (diphosphate) Energy Flow and Chemical Recycling in Ecosystems Energy flows into ecosystem as sunlight and ultimately leaves as heat, while the chemical elements essential to life are recycled. Energy is the capacity to cause change. It is also the ability to rearrange a collection of matter. In the environment different forms of energy exist: Kinetic, Light and Potential energy. Forms of Energy Kinetic - energy associated with relative motion of objects. Thermal energy - type of kinetic energy associated with random movement of atoms. When thermal energy is transferred in the form of heat. Light Energy - main energy source is the sun and powers photosynthesis (anabolic process). Potential Energy - possessed energy of a matter at rest (non- moving form) Chemical energy - potential energy released in a chemical reaction. Laws of Energy Transformation Thermodynamics is the study of energy transformations that occurs in a system (collection of matter). Living systems are considered as open systems because energy and matter are transferred between systems and the surroundings. Laws of Energy Transformation Thermodynamics is the study of energy transformations that occurs in a system (collection of matter). Living systems are considered as open systems because energy and matter are transferred between systems and the surroundings.  1st Law: The energy of the universe is constant. Energy can be transferred and transformed but it cannot be created nor destroyed. Plants do not produce energy, but transforms energy from the sun. Some energy becomes unavailable to do work because most is lost as heat. Transfer of energy and transformation makes the matter more disordered. Disorder of matter is measured through entropy.  1st Law: The energy of the universe is constant. Energy can be transferred and transformed but it cannot be created nor destroyed. Plants do not produce energy, but transforms energy from the sun. Some energy becomes unavailable to do work because most is lost as heat. Transfer of energy and transformation makes the matter more disordered. Disorder of matter is measured through entropy.  2nd Law: Every energy transfer or transformation increases the energy of the universe. i.e In a room full of people, breathing increases entropy since all are exhaling carbon dioxide. Organisms as open system increase order as long as the order in their surroundings decreases. This shows that as living organism transfers/transforms energy to its surroundings, the disorder increases, thus increases entropy.  2nd Law: Every energy transfer or transformation increases the energy of the universe. i.e In a room full of people, breathing increases entropy since all are exhaling carbon dioxide. Organisms as open system increase order as long as the order in their surroundings decreases. This shows that as living organism transfers/transforms energy to its surroundings, the disorder increases, thus increases entropy.  Equilibrium and Metabolism Equilibrium = NO WORK. This usually happened in isolated systems that reach equilibrium. A cell that reaches the state of equilibrium is DEAD. A normal cell is not in equilibrium, because its products are not accumulated within its system, INSTEAD the products becomes a reactant in the next step.  Equilibrium and Metabolism Equilibrium = NO WORK. This usually happened in isolated systems that reach equilibrium. A cell that reaches the state of equilibrium is DEAD. A normal cell is not in equilibrium, because its products are not accumulated within its system, INSTEAD the products becomes a reactant in the next step.  Bring the following materials: ACTIVITY 1. 2. 3. Buttons Toothpick Glue gun/any glue to attach the button one by one. TRANSPORT MECHANISM  Objectives After going through this module, you are expected to: 1. Describe the structural components of the cell membrane; 2. Relate the structure and composition of the cell membrane to its function;  Objectives After going through this module, you are expected to: 3. Explain transport mechanisms in cells (diffusion, osmosis, facilitated transport, active transport); and 4. Differentiate exocytosis and endocytosis  TRANSPORT MECHANISM It refers to the different pathways and processes a cell must move substances in, out and around itself. TRANSPORT MECHANISM A Real-Life Application of Transport Mechanism A Real-Life Application of Transport Mechanism A Real-Life Application of Transport Mechanism