Hinton Scholars ProgramPhotosynthesis

Light

Fig. 10-5-1

H2O

Chloroplast

LightReactions

NADP+

PADP

i+

Light

Fig. 10-5-2

H2O

Chloroplast

LightReactions

NADP+

PADP

i+

ATP

NADPH

O2

Light

Fig. 10-5-3

H2O

Chloroplast

LightReactions

NADP+

PADP

i+

ATP

NADPH

O2

CalvinCycle

CO2

Light

Fig. 10-5-4

H2O

Chloroplast

LightReactions

NADP+

PADP

i+

ATP

NADPH

O2

CalvinCycle

CO2

[CH2O](sugar)

Evolution of Chloroplasts and Mitochondria

Why are most (but not all) plants green?

http://commons.wikimedia.org/wiki/File:Dew_on_green_Plant.jpghttp://en.wikipedia.org/wiki/Chloroplasthttp://www.pion.cz/en/article/electromagnetic-spectrum

Violet and Blue are best transmitted through clear water.

Fig. 10-18-1

Beginning of the Calvin Cycle!

Stomata

What are stomata? What do they do?

http://www.hisse.net/forum/showthread.php?t=26901&page=11

Fig. 10-19

The C4 pathway

Mesophyllcell CO2PEP carboxylase

4C3C

3CCO2

Bundle-sheathcell

CalvinCycle

Sugar

Vasculartissue

http://www.hisse.net/forum/showthread.php?t=26901&page=11

C4 Plants

PEP hydroxylase binds to CO2 more strongly than rubisco. It

will even bind CO2 at low concentrations.

These steps are isolated into different cells/compartments.

Fig. 10-20

These steps are temporally separated.

CAM Plants

Stomata are closed during the day, but open at night to let in

CO2.

http://www.hisse.net/forum/showthread.php?t=26901&page=11

Fig. 10-18-3

Ribulose bisphosphate(RuBP)

3-Phosphoglycerate

Short-livedintermediate

Phase 1: Carbon fixation

(Entering oneat a time)

Rubisco

Input

CO2

P

3 6

3

3

P

PPP

ATP6

6 ADP

P P61,3-Bisphosphoglycerate

6

P

P6

66 NADP+

NADPH

i

Phase 2:Reduction

Glyceraldehyde-3-phosphate(G3P)

1 POutput G3P

(a sugar)

Glucose andother organiccompounds

CalvinCycle

3

3 ADP

ATP

5 P

Phase 3:Regeneration ofthe CO2 acceptor(RuBP)

G3P