Chapter 6 Capturing Solar Energy: Photosynthesis Flashcards
C3 Cycle
The cyclic series of reaction whereby carbon dioxide is fixed into carbohydrates during the light-independant reactions of photosynthesis; also called Calvin-Benson cycle.
C4 Pathway
The series of reaction in a certain plants that fixes carbon dioxide into oxaloacetic acid, which is later broken down for use in the C3 cycle of photosynthesis.
Carbon Fixation
The initial steps in the C3 cycle, in which carbon dioxide reacts with rubulose bisphosphate to form a stable organic molecule.
Chlorophyll
A pigment found in chloroplasts that captures light energy during photosynthesis; absorbs violet, blue, and red light but reflects green light.
Chloroplast
The organelle in plants and photosynthetic protists that is the site of photosynthesis; surrounded by a double membrane and containin an extensive internal membrane system that bears chlorophyll.
Crassulacean Acid Metabolism (CAM)
A varian form of photosynthesis in which carbon dioxide is incorporated into organic molecules at night, when stomata are open, and then released to the C3 cycle during the day, when the stomata are closed; used by plants in hot, dry enviroments.
Dinucleotide Phosphate (NADPH)
An energy-carrier molecule produced by the light dependent reactions of photosynthesis; transfers energy to the carbon-fixing (light-independent) reaction.
Electron Transport Chain (ETC)
A series of electron carrier molecules, found in the thylakoid membranes of chloroplasts and the inner membrane of mitochondria, that extract energy from electrons and generate ATP or other energetic molecules.
Light-harvesting complex
In photosystems, the assembly of pigment molecules (chlorophyll and accessory pigments) that absorb light energy and transfer that energy to electrons.
Mesophyll
Loosely packed parenchyma cells beneath the epidermis of a leaf.
Nicotinamide Adenine Dinucleotide (NADH)
An electron carrier molecule produced in the cytoplasmic fluid by glycolysis and in the mitochondrial matrix by the Krebs cycle; subsequently donates electrons to the electron transport chain.
Photorespiration
A series of reaction in plants in which O2 replaces CO2 during the C3 cycle, preventing carbon fixation; this wasteful process dominates when C3 plants are forced to close their stomata to prevent water loss.
Photosynthesis
The complete series of chemical reaction in which the energy of light is used to synthesize high-energy organic molecule, normally carbohydrates, from low-energy inorganic molecules, normally carbon dioxide and water.
Photosystem
In thylakoid membranes, a light-harvesting complex and its associated electron transport system.
Reaction Center
In the light-harvesting complex of a photosystem, the clorophyll molecule to which light energy transferred by the antenna molecules (light-absorbing pigments); the captured energy ejects an electron from the reaction center clorophyll, and the electron is trasnferred to the electron transport system.
