Photosynthesis

Question 1

Photosynthesis overall equation

Answer 1

6CO2 and 6H2O and light energy to 6O2 and C6H12O6, anabolism

Question 2

Photosynthesis as redox reaction

Answer 2

Electrón flow in opposite direction, H2O is plot and electrons form more polar H-O bonds are transferred along with the protons to CO2 reducing it to a sugar and generating less polar C-H bonds, energy required for this process is derived form sunlight, it is stored at PE in the C-H bonds of sugar

Question 3

Chloroplast structure

Answer 3

Double membrane, stroma, granulated made of thylakoid discs

Question 4

Two overall processes in photosynthesis

Answer 4

Light reaction that splits H2O to release O2, electrons form this reaction are captured by chlorophyll and raised to a higher energy level, they are moved down ETC similar to those in mitochondria, released energy is used to generate ATP and. Reduced electron carrier- NADPH and then a DARK reaction that fixes CO2 called the Calvin cycle

Question 5

Electromagnetic spectrum

Answer 5

Shorter wavelength has higher energy, longer wavelength has lower energy

Question 6

Why are leaves green?

Answer 6

Green wavelength is reflected while other wavelengths are absorbed, high transmittance of green light in chlorophyll solution low transmittance of blue

Question 7

Types of chlorophyll

Answer 7

Chlorophyll a and b, CHO in b and CH3 in a

Question 8

Absorbance of chlorphyll a, b , and carotenoids

Answer 8

LOOK UP

Question 9

Carotenoids

Answer 9

Alter the absorbance properties of photosynthetic mechanisms

Question 10

Light absorbing pigments with other proteins

Answer 10

To form two photosystems locate din thylakoid membrane

Question 11

Photo system I absorbance wavelength

Answer 11

700nm

Question 12

Photo system II wavelength absorbance

Answer 12

680nm

Question 13

Excitation of isolated chlorophyll by light

Answer 13

Photo excited electrons which released heat and the photon as energy, then once energy is released returns to the ground state

Question 14

Photo system structure

Answer 14

In membrane, light harvesting complexes have pigment molecules where energy is transferred, and reaction center complex has a primary electron acceptor with a special pair of chlorophyll a molecules

Question 15

P680 (photosystem II)

Answer 15

When excited electron is passed form chlorophyll P680 it leaves the chlorophyll molecule oxidized, the loss of electron is idled by the splitting of water, which released 2O2, 2 proton, and 2 electrons (water reduced the chlorophyll), hydrogen is released to thylakoid lumen creating a proton gradient across thylakoid membrane, energy from electrons is also used to maintain this proton gradient which generates ATP

Question 16

PS II to PS I

Answer 16

Light to pigments to P680, o primary acceptor, to Pq, to cytochrome complex, to Pc to P70 where light excites their pigment molecules and primary acceptor in PS I takes place

Question 17

PS I to NADPH

Answer 17

Primary acceptor in PS I, Fd (Ferredoxin) , to NADP plus re-educates, which produces NADOH to NADP plus and H plus

Question 18

Non cyclic electron transfer

Answer 18

Can generate ATP and NADPH

Question 19

Cyclic electron transfer

Answer 19

Generates ATP, not NADH (Calvin cycle uses more ATP and NADPH), and provide the extra ATP

Question 20

Chemiomosis in chloroplast

Answer 20

FINDDDD

Question 21

End products of light reactions

Answer 21

NADPH and ATP (goes to Calvin cycle)

Question 22

3 intermediate proteins for electrons in light rxns

Answer 22

Plastoquinone, plastocyanin, ferredoxin

Question 23

Calvin cycle phases

Answer 23

Carbon fixation, reduction, regeneration of CO2 acceptor (RuBP)

Question 24

Calvin cycle outputs for light reactions

Answer 24

ADP and inorganic phosphate and NADP+, other output from CO2 is CH2O (sugar)

Question 25

Carbon fixation

Answer 25

3CO2 in rubisco form 6 3-phophoglycerate and produces 6 ADP from using ATP, fixes one CO2 into a five carbon compound (RuBP), unstable and forms 2 3-carbon molecule (3-phosphoglycerate) RUBISCO (enzyme) catalyzes fixation of carbon dioxide (lots in leaf plants)

Question 26

Reduction

Answer 26

Phosphorylation 3-phosphoglycerateto form 3-bisphosphoglyerate using ATP (3 carbons, 2 phosphates per, 6 total), then NADPH (reduces previous molecule) is used to make glyceraldehyde 3-phosphate (G3P) (3 carbons, 1 phosphate, 6 total), ONE G3P triose sugar is produced (glucose and others)

Question 27

G3P two pathways

Answer 27

1. Could be used to generate other sugars for storage and energy 2. Used to generate more ribulose biphosphate (RuBP) that can be used to maintain the Calvin Cycle, FROM 3 CO2, 1 G3P used for sugar, 5 G3P used to synthesize more RuBP

Question 28

Regeneration of RuBP

Answer 28

5 G3P react with 3 ATP (which produces 3ADP) to make 3 RuBP (5 carbon, 2 phosphate each, 3 total)

Question 29

Two fates for G3P

Answer 29

One third ends up as starch, two thirds converted o disaccharide sucrose for glucose and fructose energy

Question 30

Carbon numbers in calvin cycle

Answer 30

18 with addition of 3 CO2, when one G3P is removed later on, 15 carbons remain