Photosynthesis Exam 3

Question 1

• photosynthesis process

Answer 1

light to chemical energy - sugar molecules

Question 2

• chloroplast def

Answer 2

light absorbent organelles

Question 3

• chlorophyll def

Answer 3

light - absorbing molecuel in chloroplasts - typical cell has 30-40 chloros

Question 4

• stomata def

Answer 4

tiny pores in leaf - for CO2 / O2 transfer (oxygen escapes as O2)

Question 5

• stroma

Answer 5

thick fluid within inner membrane

Question 6

• thylakoids

Answer 6

membranous sacs within the stromA

Question 7

• grana

Answer 7

stacks of thylakoids with chlorphyll in there

Question 8

• 2 stages of photosynthesis

Answer 8

light reactions and Calvin cycle

Question 9

• light reactions overview

Answer 9

chlorophyll absorb light → ATP and NADPH // NADP+ reduced to NADPH - water split = é source and O2 byproduct

Question 10

• Calvin cycle overview

Answer 10

enzymes dissolved in Stroma depends on the ATP and NADPH from light reactions - incorporates CO2 = carbon fixation

Question 11

• sunlight E type/ how travels

Answer 11

radiation - travels through space as rhythmic waves - short wavelngth more intense - RED longer

Question 12

• explain chlorophyll which light works best

Answer 12

blue-violet and orange-red works best - green reflected

Question 13

• explain chlorophyll a and chlorophyll b

Answer 13

chloro a directly in light reactions - absorbs blue-violet/red light // chloro b blue & orange light - converys E to chloro a

Question 14

• carotenoids

Answer 14

absorb blue-green light - absorb/dissipate EXCESSIVE energy - cause yellow fall colours - decrease chlorophyll levels - in thylakoid

Question 15

• what is a photon

Answer 15

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

Question 16

• explain photosystems

Answer 16

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

Question 17

• list steps of light reactions ATP + NADPH producton

Answer 17

1. (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

Question 18

• similarities between light reactions and cell resp

Answer 18

é transport chain pumps H+ ions across membrane (thylakoid membrane)

Question 19

• difference bw resp and photosynth

Answer 19

food orovides hugh E é in resp - photons provide high E in photosynth

Question 20

• do light reactions produce any sugar

Answer 20

no

Question 21

• why is calvin cycle a cycle

Answer 21

starting material is regenerated

Question 22

• calvin cycle inputs/outputs

Answer 22

CO2 + the light rxn ATP + NADPH - output G3P - used to make glucose

Question 23

• C3 vs C4 plants

Answer 23

C3 use CO2 from air - first compound in calvin cycle // C4 4 carbon before calvin cycle - stomata mostly closed //

Question 24

• explain CAM plants

Answer 24

ie pineapples - cacti - open stomata admit CO2 at night

Question 25

• light reaction is “2 scheme” fact

Answer 25

fact

Question 26

• HS- vs FeS

Answer 26

HS- reduced - FeS oxidized