Photosynthesis Overview

The process by which plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll.

A double membrane-bound organelle found in plant cells that is responsible for photosynthesis.

A flattened, sac-like membrane structure found inside chloroplasts that contain chlorophyll and are involved in the light-dependent reactions of photosynthesis.

The process by which light energy is captured and converted into chemical energy in the form of ATP and NADPH. It occurs in the thylakoid membrane.

A cyclic series of biochemical reactions that occur in the stroma of chloroplasts during photosynthesis, where carbon dioxide is converted into glucose using the energy from ATP and NADPH.

Photosystem II (PSII) is a complex of proteins and pigments found in the thylakoid membrane of chloroplasts. It plays a crucial role in the light-dependent reactions of photosynthesis by absorbing light energy and using it to excite electrons.

The electron transport chain (ETC) in photosynthesis is a series of protein complexes embedded in the thylakoid membrane. It facilitates the movement of excited electrons from Photosystem II to Photosystem I, releasing energy along the way to power proton pumping.

The proton pump is a protein complex in the thylakoid membrane that uses the energy released during electron transport to move protons (H+) from the stroma to the thylakoid lumen. This creates a proton gradient across the thylakoid membrane.

The electrochemical gradient in photosynthesis refers to the difference in both proton concentration and electrical charge across the thylakoid membrane. This gradient is essential for ATP synthesis.

Photosystem I (PSI) is another complex of proteins and pigments in the thylakoid membrane of chloroplasts. It absorbs light energy to re-energize the electrons that have passed through the electron transport chain.

NADP+ (nicotinamide adenine dinucleotide phosphate) is a coenzyme that serves as the final electron acceptor in the light-dependent reactions of photosynthesis. When NADP+ accepts electrons, it becomes NADPH, which carries these high-energy electrons to the Calvin cycle.

ATP synthase is an enzyme located in the thylakoid membrane that uses the energy stored in the proton gradient to synthesize ATP (adenosine triphosphate), the primary energy currency of cells.

Chemiosmosis in photosynthesis refers to the movement of protons (H+) down their electrochemical gradient through ATP synthase. This movement powers the synthesis of ATP.

Photophosphorylation is the process of ATP synthesis in photosynthesis powered by light energy. It's a key step in capturing sunlight's energy to make ATP.

Glycolysis is a metabolic pathway that occurs in the cytoplasm of cells. It involves the breakdown of glucose into pyruvate, generating a small amount of ATP and NADH.

The Krebs cycle (also known as the citric acid cycle) is a series of biochemical reactions that occur in the mitochondrial matrix. It further oxidizes pyruvate from glycolysis, generating more ATP, NADH, and FADH2.

The electron transport chain (ETC) in cellular respiration is a series of protein complexes embedded in the inner mitochondrial membrane. Similar to photosynthesis, electrons from NADH and FADH2 are passed down the chain, releasing energy that is used to pump protons into the intermembrane space.

Chemiosmosis in cellular respiration is the movement of protons (H+) down their electrochemical gradient through ATP synthase located in the inner mitochondrial membrane. This movement powers the synthesis of ATP.

Oxidative phosphorylation is the process of ATP synthesis in cellular respiration that is powered by the oxidation of NADH and FADH2 via the electron transport chain. This is the main mechanism of ATP production in aerobic organisms.