Ecosystem: Life Energy PDF

ECOSYSTEM: Life Energy What is ECOSYSTEM? ECOSYSTEM: all of the communities that live in an area together with the abiotic factors in the environment Photosynthesis  Photosynthesis It is the food making by plants and other autotrophic organisms. It occurs primarily on leaves dependin...

ECOSYSTEM: Life Energy What is ECOSYSTEM? ECOSYSTEM: all of the communities that live in an area together with the abiotic factors in the environment Photosynthesis  Photosynthesis It is the food making by plants and other autotrophic organisms. It occurs primarily on leaves depending on the presence of the chlorophyll. Autotrophic organisms require light, carbon dioxide, and water to make food. Learning Station 1A Learning Station 1B Learning Station 2 Raw Materials Products sunlight oxygen chlorophyll sugar (food, carbon dioxide glucose) water  Typical Parts of the Leaves Upper and Lower Epidermis It protects the leaves and has nothing to do with photosynthetic processes. Mesophyll Spongy Layer It has the most number of chloroplasts that contain the chlorophyll. They are important in trapping light energy from the sun. Vascular Bundles They serve as transporting vessels of manufactured food and water. Stomata It is the tiny pore in the outer layer (epidermis) of a plant leaf or stem that controls the passing of water vapor and other gases into and out of the plant. Carbon dioxide and oxygen were collected in the spongy layer and enters and exits the leaf through the stomata. Where in the plant cell does this process occur?  Chloroplasts Contain green photoreceptor pigment, chlorophyll. Found in the ground tissue of leaves and stems. The site of photosynthesis Chloroplasts Found in leaves, and unripened fruit. These are the only areas that can perform photosynthesis. Has an outer and an inner membrane that hold the chloroplast together.  Parts of Chloroplasts Outer and Inner Membranes These act as protective coverings and keep chloroplast structures enclosed. Stroma It is a dense fluid within the chloroplast that lies inside the envelope but outside the thylakoid membrane. This is the site of conversion of carbon dioxide to carbohydrates (sugar). Thylakoids These serve as the sites of conversion of light energy to chemical energy.  Chlorophyll absorbs white light but it look green because white light consists of three primary colors: red, blue and green. What parts of the plant are involved in the reaction? sunlight carbon + water glucose + oxygen dioxide chlorophyll 6 CO2 + 6 H2O C6H12O6 + 6 O2 from air from soil stored as released to air via stomata via roots starch in leaves via stomata in in leaves leaves Chemical Reaction of Photosynthesis Chlorophyll Carbon Dioxide + Water Glucose + Oxygen Sunlight Chemical Reaction of Cellular Respiration Glucose + oxygen carbon dioxide + water + ATP Two Stages of Photosynthesis Light-dependent Reaction Calvin Cycle (dark reaction)  Light-dependent Reaction It happens in the presence of light. it occurs in the thylakoid membrane and converts light energy to chemical energy. Water, one of the raw materials of photosynthesis, is utilized during this stage and facilitates the formation of free electrons and oxygen. The energy harvested during this stage is stored in the form of ATP (Adenosine Triphosphate) and NADPH (Nicotinamide Adenine Dinucleotide Phosphate Hydrogen). This products will be needed in the next stage to complete photosynthetic process. Calvin Cycle (Dark Reaction) It is a light-independent phase that takes place in the stroma and converts carbon dioxide into sugar. This stage does not directly need light but needs the products of light reaction. This is why it occurs immediately after the light- dependent phase. Cellular Respiration The food must be digested to simple forms such as glucose, amino acids, and triglycerides. These are then transported to the cells. The immediate energy source of the cells is glucose. Glucose inside the cell is broken down to release the stored energy. This stored energy is harvested in the form of adenosine triphosphate (ATP). ATP is a high-energy molecule needed by working cells. 3 Major Steps in Breaking Down Glucose Glycolysis Krebs cycle Electron Transport Chain  Glycolysis It is the broken down of compound such as glycogen or glucose by enzymes, producing pyruvic or lactic acid and releasing energy for use in the body. In glycolysis, the 6-carbon sugar, glucose, is broken down into two molecules of a 3-carbon molecule called pyruvate. This change is accompanied by a net gain of 2 ATP molecules and 2 NADH molecules.  Krebs Cycle It occurs in the mitochondrial matrix and generates a pool of chemical energy (ATP, NADH, and FADH2) from the oxidation of pyruvate, the end product of glycolysis. Pyruvate is transported into the mitochondria and loses carbon dioxide to form acetyl-CoA, a 2-carbon molecule. When acetyl-CoA is oxidized to carbon dioxide in the Krebs Cycle, chemical energy is released and captured in the form NADH, FADH2, and ATP.  Electron Transport Chain It allows the release of the large amount of chemical energy stored in reduced NAD+ (NADH) and reduced FAD (FADH2). The enrgy released is captured in the form of ATP (3 ATP per NADH and 2 ATP per FADH2). It consists of a series of molecules, mostly proteins, embedded in the inner mitochodrial membrane. This phase of cellular respriation produces the greatest number of chemical energy in the form of ATP.