What process does the grass use to harness this energy?
The correct answer and explanation is:
The grass harnesses energy through a process called photosynthesis. Photosynthesis is the biochemical process by which green plants, including grasses, convert light energy from the sun into chemical energy stored in glucose (a type of sugar). This process occurs primarily in the chloroplasts of plant cells, where chlorophyll, the green pigment, captures sunlight.
The process of photosynthesis is divided into two main stages: the light-dependent reactions and the light-independent reactions (also known as the Calvin cycle).
- Light-dependent reactions: These occur in the thylakoid membranes of the chloroplasts and require sunlight to happen. When sunlight hits the chlorophyll, it excites electrons, which are then passed through a series of proteins in the electron transport chain. This process creates two important molecules: ATP (adenosine triphosphate), which provides energy for the plant, and NADPH (nicotinamide adenine dinucleotide phosphate), which carries electrons. During this phase, water molecules are split to release oxygen gas (O₂) as a byproduct.
- Light-independent reactions (Calvin cycle): This phase takes place in the stroma of the chloroplasts and does not require sunlight directly. The ATP and NADPH produced in the light-dependent reactions provide the energy and electrons needed to convert carbon dioxide (CO₂) from the air into glucose. The Calvin cycle involves a series of enzyme-driven reactions, ultimately producing glucose, which the plant can use for energy, growth, and reproduction.
Through photosynthesis, the grass is able to create its own food and store energy in the form of glucose. This energy is then used to support cellular functions, including growth, repair, and reproduction. Additionally, photosynthesis is the foundation of most ecosystems, as it provides energy for herbivores and, ultimately, carnivores.