IGCSE Coordinated Science Vocabulary Practice Test

Plants capture light energy in chlorophyll to drive a set of reactions that turn carbon dioxide and water into carbohydrates, like glucose. This process stores energy in the chemical bonds of sugars and releases oxygen as a byproduct. Light-dependent reactions harvest light to make energy carriers (ATP and NADPH), which the Calvin cycle uses to fix carbon dioxide into sugars. That combination—using light to build sugars from CO2 and water—is what we call photosynthesis. Other terms given refer to different processes: respiration releases energy from sugars using oxygen; transpiration is the loss of water from leaves; fermentation is an anaerobic way of producing energy without light.