Chapter 10: Photosynthesis

Front 1

Where does photosynthesis occur?

Back 1

In chloroplasts

Front 2

How many chloroplasts are typically in a cell?

Back 2

40 to 50 chloroplasts

Front 3

What is a thylakoid?

Back 3

Vesicle like structure in chloroplasts

Front 4

Lumen

Back 4

Interior of any sac-like structure

Front 5

Pigments

Back 5

Molecules that absorb wavelengths and protect the cells

Front 6

What color does chlorophyl A and B absorb

Back 6

Red wavelength/ blue wavelength

Front 7

What colors do cartenoids absorb?

Back 7

Colors not absorbed by chlorophyll such as green and yellow light.

Front 8

What are the 2 classes of cartenoids?

Back 8

Carotenes and xanthophylls

Front 9

How do cartenoids protect chlorophyll molecules?

Back 9

Cartenoids "quench" free radicals by accepting or stabalizing unpaired electrons.

Front 10

What are Flavenoids?

Back 10

Flavenoids are accesory pigments that absorb UV light.

Front 11

Whats the base structure of Chlorophyl A and B?

Back 11

A long tail made out of isoprene subunits and a "head" consisting of a large ring structure with Mg in the middle.

Front 12

Whats the purpose of the "tail" in Chlorophyl A and B?

Back 12

Keeps the molecule embeded in the thylakoid membrane.

Front 13

Whats the purpose of the "head" in Chlorophyl A and B?

Back 13

Light absorbtion.

Front 14

What happens when the antenna complex absorbs blue or red light?

Back 14

An e- gets excited and tranfers to a nearby chlorophyl molecule.

Front 15

What happens when green light hits an antenna complex?

Back 15

Nothing. No resonance occurs

Front 16

What is resonance in photosynthesis?

Back 16

Where e- transfer to nearby chlorophyl molecule.

Front 17

What occurs in flourescence in photosynthesis?

Back 17

Photon excites an electron and the electron drops back down in energy. Releasing light and heat

Front 18

What is a reaction center in chlorophyll?

Back 18

Its a special pigment where the e- gets excited and picked up. By either Pheophytin(photosystem II) or Ferrodoxin(photosystemI)

Front 19

What is pheophytin and its role in photosystem II?

Back 19

Pheophytin is structurally the same as chlorophyll except it has no Mg molecule in its head. It accepts electrons and transports them to Plastoquinone(PQ) which then tranfers it to the Electron transport chain.

Front 20

Which electron acceptor gets used in Photosystem II

Back 20

Pheophytin

Front 21

Which electron acceptor is used in photosystem I

Back 21

Plastocyanin

Front 22

What is plastquinone?

Back 22

A quinone(small hydrophobic molecule) that is lipid soluble and not anchored to a protien.

Front 23

What is plastoquinones 1st function?

Back 23

Plastoquinones shuttles electrons from pheophytin to more electronegative molecules in the ETC(electron transport chain) including cytochrome.

Front 24

What is plastoquinones 2nd function?

Back 24

Plastoquinone gathers protons after ETC transporting them to the lumen side of the thylakoid membrane lowering the pH of the lumen side of the thylakoid membrane.

Front 25

What is the net result of ETC

Back 25

Like cellular resperation the ETC creates a proton gradient, which creates a proton motive force that pushes ATP synthase.

Front 26

What is photophosphorylation?

Back 26

ATP synthase creating ATP from ADP+Pi in a chloroplast.

Front 27

How does Photosystem II get electrons to excite for its inital step?

Back 27

Water gets oxidized producing this reaction

2H2O -> 4H + 4e + O2 the 4e go to the reaction center for photosystem II

Front 28

Whats oxygenic photosynthesis?

Back 28

Organisms thatbproduce oxygen in photosystem II

Front 29

Whats anoxygenic photosynthesis?

Back 29

A non oxygen producing organism.

Front 30

Whats the end result of Photosystem II?

Back 30

ATP production through Photophosphorylation, and to transfer e- to plastocyanin

Front 31

What is plastocyanin?

Back 31

Small diffusable protien.

Front 32

What is Plastocyanins(PC) function?

Back 32

Picks up 1000 electrons amd delivers them to photosystem I/ replaces P700 electrons

Front 33

What is the end result of photosystem I?

Back 33

2 NADPH

Front 34

What is the enhancement effect?

Back 34

When Lights of wavelength 680 are shown only photosystem II works efficiently, while the other slows down. When wavelengtsh of 700 are shown its inversed with photosystem I working more efficiently. The enhanvement effect is when both lights are shown and they both produce at their maximum rate

Front 35

What is cyclic photophosphorylation?

Back 35

Photosystem transports electrons back to ETC to help reduce CO2 and produce sugar.

Front 36

Does cyclic photophosphorylation co exist with the Z scheme?

Back 36

Yes it does

Front 37

What is the Z scheme?

Back 37

Its the pathway representation of events between photosystem II and I.

Front 38

What is RuBP?

Back 38

Rubisco 1, 5 biphosphate.

Front 39

What are the steps to the calvin cycle?

Back 39

1.Fixation

2.Reduction

3. Regeneration

Front 40

What is fixation in the calvin cycle?

Back 40

The calvin cycle begins when CO2 reacts with RuBP. Fixes carbon and produces 2 molecules of 3 -phosphoglycerate

Front 41

What is reduction phase in the calvin cycle?

Back 41

3-phosohoglycerate is phosphorylated by ATP and then reduced by electrons from NADPH. Producing glyceraldhyde-3-phosphate. (G3P)

Front 42

What is G3P?

Back 42

Glyceraldhyde-3-phosohate

Front 43

What is a byproduct of the reduction phase?

Back 43

Glucose and fructose.

Front 44

What is the regeneration phase in the calvin cycle?

Back 44

Thenrest of the G3P keeps the cycle going by serving as the substrate for the third ohase in the cycle.

Front 45

What is photorespiration?

Back 45

Consumes oxygen and produces CO2

Front 46

Whats the difference between photosynthesis and photoresperation?

Back 46

Photosynthesis uses Co2 for calvin cycle creating 2 3-phosphoglycerate

While photoresperation produces one 3 phosphoglycerate(used in calvin cycle) and one 2-phosphoglycolate(releasing co2 using up ATP)

Front 47

What does photoresperation do?

Back 47

It undoes photosynthesis.

Front 48

When is photoresperation more likely to occur?

Back 48

When oxygen concentrations are high and CO2 concentrations are low.

Front 49

What is C3, and C4 photosynthesis?

Back 49

When Co2 fixation occurs it produces a 4 carbon. Sugar.

Front 50

What is PEP carboxylase?

Back 50

An enzyme that adds Carbon dioxide to RuBP

Front 51

Difference between C4 and C3 plants?

Back 51

C3 plants have chloroplasts and rubisco in the mesophyll cells.

Front 52

Mesophyll cells

Back 52

Are near the surface of the leaf

Front 53

Steps of C4 plant

Back 53

Step 1:PEP carboxylase fixes CO2 in mesophyll cells

Step 2: the 4 carbon organic acids, travel to the bundle sheathe cells through plasmodesmata.

Step 3: 4 carbon organic acids release a CO2 molecule, rubisco uses a substrate to form a 3 phosohoglycerate.

Front 54

What is CAM?

Back 54

Crassulacean acid metabolism

Front 55

Whats the differemce between CAM plants and C3- C4 plants?

Back 55

C4 plants stockpile CO2 in cells where rubisco is not present- CAM plants store CO2 when rubisco is inactive.

C4 plants use space to seperate its reactions

CAM uses time to seperate them.