Photosynthesis Exam 3 Flashcards
(26 cards)
- photosynthesis process
light to chemical energy - sugar molecules
- chloroplast def
light absorbent organelles
- chlorophyll def
light - absorbing molecuel in chloroplasts - typical cell has 30-40 chloros
- stomata def
tiny pores in leaf - for CO2 / O2 transfer (oxygen escapes as O2)
- stroma
thick fluid within inner membrane
- thylakoids
membranous sacs within the stromA
- grana
stacks of thylakoids with chlorphyll in there
- 2 stages of photosynthesis
light reactions and Calvin cycle
- light reactions overview
chlorophyll absorb light → ATP and NADPH // NADP+ reduced to NADPH - water split = é source and O2 byproduct
- Calvin cycle overview
enzymes dissolved in Stroma depends on the ATP and NADPH from light reactions - incorporates CO2 = carbon fixation
- sunlight E type/ how travels
radiation - travels through space as rhythmic waves - short wavelngth more intense - RED longer
- explain chlorophyll which light works best
blue-violet and orange-red works best - green reflected
- explain chlorophyll a and chlorophyll b
chloro a directly in light reactions - absorbs blue-violet/red light // chloro b blue & orange light - converys E to chloro a
- carotenoids
absorb blue-green light - absorb/dissipate EXCESSIVE energy - cause yellow fall colours - decrease chlorophyll levels - in thylakoid
- what is a photon
fixed quantity of light energy - shorter wavelngth = greater photon energy - when pigment abosrbs photon - excited - release heat as és fall back down to ground state
- explain photosystems
cluster of chlorophylls - E jumps from molecule to olecule until reaction center - @ reaction center goes to PRIMARY ELECTRON ACCEPTOR - traps light- excited energy from chloro a
- list steps of light reactions ATP + NADPH producton
- (WATER SPLITTING photosystem) photons excite és - replaces by extracting from water 2. energized és pass down é transport chain to NADPH PRODUCTION PHOTOSYSTEM 3 NADPH producing photosystem transfers és to NDAP+ for NADPH
- similarities between light reactions and cell resp
é transport chain pumps H+ ions across membrane (thylakoid membrane)
- difference bw resp and photosynth
food orovides hugh E é in resp - photons provide high E in photosynth
- do light reactions produce any sugar
no
- why is calvin cycle a cycle
starting material is regenerated
- calvin cycle inputs/outputs
CO2 + the light rxn ATP + NADPH - output G3P - used to make glucose
- C3 vs C4 plants
C3 use CO2 from air - first compound in calvin cycle // C4 4 carbon before calvin cycle - stomata mostly closed //
- explain CAM plants
ie pineapples - cacti - open stomata admit CO2 at night
