Chapter 5

Question 1

Equation for Photosynthesis

Answer 1

6CO2 + 6H20 + light energy –> C6H12O6 + 6O2

Question 2

changes to earth due to photosynthesis

Answer 2

-decreased CO2 -lowered global temperature -added oxygen gas to atmosphere -formed ozone layer

Question 3

redox process in photosynthesis

Answer 3

Oxygen in H2O loses electrons (oxidized) Carbon in CO2 gains electrons (reduced)

Question 4

what are the different pigments?

Answer 4

chlorophyll a (major pigment) chlorophyll b and carotenoids (accessory pigments)

Question 5

what do the pigments do?

Answer 5

capture light energy

Question 6

what are the pigments composed of?

Answer 6

lipids

Question 7

stroma

Answer 7

fluid in inner membrane of chloroplast that contains ribosomes, DNA, enzymes

Question 8

grana

Answer 8

stacks of thylakoids suspended in stroma

Question 9

thylakoid

Answer 9

disk shaped membrane studded with photosystems

Question 10

photosystem reaction center

Answer 10

has pair of chlorophyll a molecules that perform photosynthesis; other pigments harvest light

Question 11

antenna pigments

Answer 11

capture photon energy and send it to reaction center

Question 12

2 stages of photosynthesis

Answer 12

light reactions and carbon reactions

Question 13

what happens in light reactions?

Answer 13

convert solar energy to chemical energy (stored in ATP and NADPH)

Question 14

where do light reactions occur?

Answer 14

thylakoid membranes

Question 15

NADPH

Answer 15

coenzyme that carries pairs of energized electrons

Question 16

where do energized electrons carried by NADPH come from?

Answer 16

the pair of reaction center chlorophyll molecules, which are replenished by splitting H2O molecules

Question 17

what happens in carbon reactions?

Answer 17

cell uses ATP, high energy electrons in NADPH, and CO2 to produce glucose

Question 18

where do carbon reactions occur?

Answer 18

stroma

Question 19

Photosystem II

Answer 19

begins photosynthesis and produces ATP

Question 20

what does the first ETC do?

Answer 20

creates proton gradient across thylakoid membrane (potential energy)

Question 21

what does ATP synthase do?

Answer 21

turns proton gradient into chemical energy (ATP)

Question 22

chemiosmotic phosphorylation

Answer 22

when ATP synthase turns proton gradient into ATP

Question 23

chemiosmosis

Answer 23

movement of protons across membrane

Question 24

what does the second ETC do?

Answer 24

reduces NADP+ to NADPH

Question 25

3 parts of Calvin Cycle

Answer 25

1. Carbon fixation 2. PGAL synthesis 3. Regeneration of RuBP

Question 26

Carbon fixation

Answer 26

CO2 is added to RuBP, creating an unstable 6-carbon molecule

Question 27

RuBP

Answer 27

Ribulose biphosphate (5-carbon sugar)

Question 28

PGAL synthesis

Answer 28

6-carbon product breaks down into 2 3-carbon molecules (PGAL)

Question 29

PGAL

Answer 29

phosphoglyceraldehyde: 2 of these combine to form glucose

Question 30

Regeneration of RuBP

Answer 30

rearranging remaining molecules (after PGAL synthesis) makes RuBP

Question 31

C3 pathway

Answer 31

Calvin Cycle (called C3 because 3-carbon molecule is the 1st stable compound in the pathway)

Question 32

photorespiration

Answer 32

inefficiency that ends Calvin cycle

Question 33

what causes photorespiration?

Answer 33

rubisco adds O2 instead of CO2 to RuBP

Question 34

what is lost during photorespiration?

Answer 34

loss of CO2, wasting ATP and NADPH

Question 35

what minimizes photorespiration?

Answer 35

open stomata, because O2 and CO2 are competing for rubisco's active site

Question 36

C4 plants

Answer 36

minimize photorespiration by separating light and carbon reactions into different cells 1% of plants

Question 37

C4 pathway

Answer 37

more efficient; requires less water, and there's less photorespiration

Question 38

what makes C4 plants photorespirate less?

Answer 38

bundle-sheath cells surround leaf veins, isolating area from most O2 intake

Question 39

CAM pathway

Answer 39

plants save water and energy by only opening stomata at night

Question 40

how are electrons replaced in PII?

Answer 40

water is split, and O2 is a waste product

Question 41

# Reverse Oxygen in H2O loses electrons (oxidized) Carbon in CO2 gains electrons (reduced)

Answer 41

redox process in photosynthesis

Question 42

# Reverse fluid in inner membrane of chloroplast that contains ribosomes, DNA, enzymes

Answer 42

stroma

Question 43

# Reverse stacks of thylakoids suspended in stroma

Answer 43

grana

Question 44

# Reverse disk shaped membrane studded with photosystems

Answer 44

thylakoid

Question 45

# Reverse has pair of chlorophyll a molecules that perform photosynthesis; other pigments harvest light

Answer 45

photosystem reaction center

Question 46

# Reverse capture photon energy and send it to reaction center

Answer 46

antenna pigments

Question 47

# Reverse light reactions and carbon reactions

Answer 47

2 stages of photosynthesis

Question 48

# Reverse coenzyme that carries pairs of energized electrons

Answer 48

NADPH

Question 49

# Reverse begins photosynthesis and produces ATP

Answer 49

Photosystem II

Question 50

# Reverse creates proton gradient across thylakoid membrane (potential energy)

Answer 50

what does the first ETC do?

Question 51

# Reverse turns proton gradient into chemical energy (ATP)

Answer 51

what does ATP synthase do?

Question 52

# Reverse when ATP synthase turns proton gradient into ATP

Answer 52

chemiosmotic phosphorylation

Question 53

# Reverse movement of protons across membrane

Answer 53

chemiosmosis

Question 54

# Reverse 1. Carbon fixation 2. PGAL synthesis 3. Regeneration of RuBP

Answer 54

3 parts of Calvin Cycle

Question 55

# Reverse CO2 is added to RuBP, creating an unstable 6-carbon molecule

Answer 55

Carbon fixation

Question 56

# Reverse Ribulose biphosphate (5-carbon sugar)

Answer 56

RuBP

Question 57

# Reverse 6-carbon product breaks down into 2 3-carbon molecules (PGAL)

Answer 57

PGAL synthesis

Question 58

# Reverse phosphoglyceraldehyde: 2 of these combine to form glucose

Answer 58

PGAL

Question 59

# Reverse rearranging remaining molecules (after PGAL synthesis) makes RuBP

Answer 59

Regeneration of RuBP

Question 60

# Reverse Calvin Cycle (called C3 because 3-carbon molecule is the 1st stable compound in the pathway)

Answer 60

C3 pathway

Question 61

# Reverse inefficiency that ends Calvin cycle

Answer 61

photorespiration

Question 62

# Reverse minimize photorespiration by separating light and carbon reactions into different cells 1% of plants

Answer 62

C4 plants

Question 63

# Reverse more efficient; requires less water, and there's less photorespiration

Answer 63

C4 pathway

Question 64

# Reverse plants save water and energy by only opening stomata at night

Answer 64

CAM pathway