Photosynthesis

Question 1

What supplies energy for chemical reactions

Answer 1

ATP, NADH, NADPH, FADH2

Question 2

Cellular Respiration

Answer 2

the oxidation of organic molecules to generate ATP

• CO2 is byproduct
• Performed by all living cells

Question 3

Redox Reactions

Answer 3

Reaction involving transfer of electrons

Question 4

Redox Reagent

Answer 4

chemical that catalyzes redox reactions

-come in oxidized and reduced forms

Question 5

Oxidized forms of redox reagents

Answer 5

NADP+ NAD+ FAD

Question 6

Reduced forms of redox reagents

Answer 6

NADPH, NADH, FADH2

-Reactive forms b/c have an extra electron at a high energy level

Question 7

Steps of redox reaction

Answer 7

1. Reduction of redox reagent
2. Subsequent oxidation of the reagent
3. Leaves behind a proton (that gets used later)

Question 8

How to make ATP

Answer 8

ADP+Pi

-Requires energy and ATP-synthase

Question 9

Photosynthesis

Answer 9

Conversion of light energy into chem energy (carbs)

• Uses CO2 and H2O, creates carbs and gives off O2 and H2O
• Light reactions and Calvin Cycle

Question 10

Light Reactions

Answer 10

Uses light energy to make NADPH and H+

• Reagent is H2O
• Produces ATP (sent to calvin cycle)
• O2 is byproduct

Question 11

Calvin Cycle

Answer 11

Fixes CO2 to create sugars

-needs NADPH and ATP for energy

Question 12

Visible Light

Answer 12

Band along electromagnetic spectrum

-sufficient energy to excite molecules and cause reactions

Question 13

Pigments

Answer 13

Substances that absorb some wavelength of light and reflect others

Question 14

Absorption Spectrum

Answer 14

Range of absorbed and reflected wave lengths

• specific for each pigment
• Chlorophyll and accessory pigments

Question 15

Chlorophyll

Answer 15

Absorbs blue and red light

• Reflects green light
• Main pigment of photosynthesis

Question 16

Accessory Pigments

Answer 16

Chlorophyll b, carotenoids

-Different absorption spectrum than chlorophyll

Question 17

Chloroplast Structure

Answer 17

• Outer membrane
• Inner membrane: thylakoid and grana
• Stroma:plastid goo

Question 18

Grana Membranes

Answer 18

Binds chlorophyll, accessory pigments, photosystems, electron transport proteins, ATP synthase
-Runs light reactions

Question 19

Photosystems

Answer 19

Group of pigment molecules whose purpose is to absorb light

• 250-400 pigment molecules
• Antenna complex and reaction center

Question 20

Antenna Complex

Answer 20

Pass light energy to reaction center

-All but 2 of the pigment molecules

Question 21

Resonance Energy Transfer (RET)

Answer 21

Light energy is absorbed by a pigment molecule in antenna complex

• Energy is passed to a neighboring molecule
• Energy hits reaction center

Question 22

Reaction Center

Answer 22

An electron is energized–> jumps off a chlorophyll a

Question 23

PSII structures

Answer 23

Antenna complex

• reaction center
• Oxygen Evolving complex (OEC)

Question 24

PSII Functions

Answer 24

Phosphorylation and photolysis

Question 25

PSII Phosphorylation

Answer 25

1. Light energy excites pigment molecules in PSII 2. RET 3 Reaction center loses an electron 4. Electron is passed down electron transport proteins 5. Energy is used to pump H+ against gradient 6. Photophosphorylation (Protons flow through ATP-synthase to make ATP)

Question 26

Photolysis

Answer 26

Water splits to create Oxygen, electrons, protons - electrons go to PSII - Protons go through ATP-synthase

Question 27

PSI Reduction

Answer 27

1. Light energy excites pigment in PSI 2. RET 3. Reaction center loses an electron 4. Electron travels down electron transport proteins 5. Electron reduces NADP+ to NADPH

Question 28

Where does PSII get electrons replaced from?

Answer 28

Photolysis

Question 29

Where does PSI get electrons replaced from?

Answer 29

PSII

Question 30

Energy products from light reactions

Answer 30

6 ATP from PSII 6 NADPH from PSI -Goes to Calvin Cycle

Question 31

Cyclic Electron Flow

Answer 31

Electrons lost by PSI can be used to pump protons across the membrane - Generates extra ATP needed for Calvin Cycle - Doesn't reduce NADP+ - The electron is passed back to PSI