Photosynthesis Flashcards
What is photosynthesis, and where does it occur?
Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy (glucose) using carbon dioxide and water. It occurs in chloroplasts, primarily in plant leaves.
Describe the structure and function of chloroplasts.
Chloroplasts are specialized organelles in plant cells where photosynthesis takes place. They contain chlorophyll, which captures light energy, and various membranes for energy conversion and sugar production.
Explain the two stages of photosynthesis: the light-dependent reactions and the Calvin Cycle (light-independent reactions).
The light-dependent reactions occur in the thylakoid membranes and involve capturing light energy to produce ATP and NADPH. The Calvin Cycle, in the stroma, uses ATP and NADPH to convert carbon dioxide into glucose.
Discuss the role of pigments, particularly chlorophyll, in photosynthesis.
Chlorophyll and other pigments absorb specific wavelengths of light for photosynthesis. Chlorophyll a and chlorophyll b are the primary pigments responsible for capturing light energy.
Explain the importance of the electron transport chain in the light-dependent reactions.
The electron transport chain transfers electrons from photosystem II to photosystem I, generating a proton gradient in the thylakoid space. This gradient powers ATP synthesis via chemiosmosis.
Describe the role of the Calvin Cycle in carbon fixation and sugar production.
The Calvin Cycle uses carbon dioxide from the atmosphere to produce glucose and other organic molecules. It involves a series of enzyme-catalyzed reactions that convert CO2 into carbohydrates.
Explain how environmental factors such as light intensity, temperature, and CO2 concentration can affect the rate of photosynthesis.
Light intensity, temperature, and CO2 concentration influence the rate of photosynthesis. Low light, extreme temperatures, or limited CO2 can limit photosynthesis.
Discuss the interconnection between photosynthesis and cellular respiration in terms of reactants and products.
The products of photosynthesis (glucose and oxygen) are used as reactants in cellular respiration, and the products of respiration (carbon dioxide and water) are used as reactants in photosynthesis. These processes are interconnected in the cycling of energy and matter in ecosystems.
