Chapter+6+Vocab

**grana** - stacks of thylakoids in a chloroplast **stroma** - in plants, the solution that surrounds the thylakoids in a chloroplast **wavelength** - the distance between crests in a wave ** pigment ** - in plants, a compound that absorbs light and imports colors **carotenoids** - a light absorbing compound that functions as an accessory pigment in photosynthesis **photosystem** - in plants, a unit of hundreds of chlorophyll & carotenoid pigment molecules in the thylakoid membrane **primary electron accepter** - a molecule in the thylakoid membrane that accepts the electrons that chlorophyll a loses in the light reactions **ATP synthase** - an enzyme that catalyzes the synthesis of ATP from ADP and phosphate **chemiosmosis** - a process in chloroplasts and mitochondria in which the movement of protons down their concentration gradient across a membrane is coupled to the synthesis of ATP ** NADP+ -** an organic molecule that accepts electrons during redox reactions **C3 plant** - plant that uses the Calvin cycle only to fix carbon dioxide ** C4 pathway ** - enables certain plants to fix CO2 into 4-carbon compounds ** Calvin cycle ** - a series of biochemical reactions that occur in the stroma of chloroplasts during photosynthesis ** CAM ** - a biochemical pathway where CO2 is incorporated into organic acids at night and released for fixation in the Calvin cycle during the day **carbon fixation** - the incorporation of carbon dioxide into organic compounds **PGA** - a 3-carbon molecule found in 1st step of Calvin cycle **PGAL** - a 3-carbon molecule formed in 2nd step of Calvin cycle that can leave the cycle and be used to make other organic compounds ** RuBP ** - it combines with CO2 at the start of the photosynthetic process in green plants **stoma** - pores located on the underside of leaves, aids in gas exchange
 * photosynthesis **- the conversion of light energy into chemical energy stored in organic compounds
 * biochemical pathway ** - a series of chemical reactions in which the product of one reaction is consumed in the next reaction
 * light reactions ** - the initial reactions in photosynthesis, including the absorption of light by photosystems I and II, the passage of electrons along the electron transport chains, the production of NADPH+ and O2, and the synthesis of ATP through chemiosmosis
 * visible spectrum -** the portion of sunlight perceived by the human eye as various colors
 * chlorophylls ** - light absorbing pigments used in photosynthesis
 * accessory pigment ** - a pigment that absorbs light energy & transfers energy to chlorophyll A in photosynthesis
 * electron transport chain ** - molecules in the thylakoid membrane that use someof the energy in electrons to pump protons across the membrane
 * adenosine diphosphate (ADP) ** - a substance involved in the energy metabolism formed by the breakdown of ATP