1.3 Describe the roles of photosynthesis and respiration in ecosystems. Photosynthesis is the process by which plant cells capture energy from sunlight and use it to combine carbon dioxide and water to make sugars (glucose) and oxygen. All living things ultimately depend on this process. Plants use chlorophyll to capture the suns energy. Carbon dioxide + water Sunlight Sugars (glucose) + oxygen Chlorophyll Respiration is the process by which cells obtain energy. In this process, organic molecules (sugars) are broken down to produce carbon dioxide and water and energy is released (in form ATP). 1.4 Identify uses of energy by organisms. - Synthesis of complex molecules (carbohydrates, lipids, proteins, nucleic acids) - Growth and repair of cells (differentiation, elongation, division) - Active transport across membranes - Functioning of special cells requiring extra energy (nerves, muscles etc.) - Transport of materials within organisms 1.5 Identify the general equation for aerobic cellular respiration and outline this as a summary of biochemical reactions. Oxygen + Sugars (gluc