chapter 10 Flashcards
absorption spectrum
a graph plotting a pigment’s light absorption vs wavelength
action spectrum
a profile of the relative effectiveness of different wavelengths, confirms the effectiveness of violet-blue and red light
autotrophs
self-feeders that sustain themselves without eating anything derived from other organisms
bundle-sheath cells
where photosynthesis is completed- cells arranged in tightly packed sheaths around the leaf veins
C3 plants
the initial fixation of carbon dioxide via rubisco forms a two-carbon compound
C4 plants
minimize the cost of photorespiration by incorporating carbon dioxide into a four carbon compound as the first product of the calvin cycle
calvin cycle
makes sugar from carbon dioxide using the ATP and NADPH generated during the light reactions
carbon fixation
incorporating carbon dioxide into organic molecules
carotenoids
yellow or orange and absorb violet and blue-green light
chlorophyll
the pigment that gives their green color
chlorophyll a
the key light capturing pigment that participates directly in light reactions
chlorophyll b
an accessory pigment
chloroplasts
organelles in plant cells and other photosynthetic organisms that begin the chemical reactions of photosynthesis
crassulacean metabolism
how succulents and other plants conserve water. they open their stoma at night and incorporate carbon dioxide into organic acids that are stored in the vacuoles
cyclic electron flow
photoexcited electrons cycle from Fd to the cytochrome complex of being transferred to NADP+
electromagnetic spectrum
the entire range of electromagnetic energy or radiation
glyceradlehyde-3-phosphate (G3P)
a sugar involved in the calvin cycle
heterotrophs
obtain organic material from other organisms; they are the consumers of the biosphere
light harvesting complex
transfer the energy of photons to the chlorophyll a molecules in the reaction center complex
light reactions
happen in the thylakoids; split H2O, providing electrons and protons (H+); release O2 as a by-product; reduce the electron acceptor NADP+ to NADPH; generate ATP from ADP by photophosphorylation
linear electron flow
the primary pathway involves both photosystems and produces ATP and NADPH using light energy
PEP carboxylase
enzyme that catalyzes the production of the four carbon precursors is catalyzed in C4 plants
mesophyll
the interior tissue of the leaf
photorespiration
rubisco binds with oxygen instead of carbon dioxide producing a two-carbon compound
