Photosynthesis

Page
3

Slide 23

The Calvin cycle (in the stroma) forms sugar from CO2, using ATP and NADPH

The Calvin cycle begins with carbon fixation, incorporating CO2 into organic molecules

Slide 24

Light

Fig. 10-5-1

H2O

Chloroplast

Light

Reactions

NADP+

P

ADP

i

+

Slide 25

Light

Fig. 10-5-2

H2O

Chloroplast

Light

Reactions

NADP+

P

ADP

i

+

ATP

NADPH

O2

Slide 26

Light

Fig. 10-5-3

H2O

Chloroplast

Light

Reactions

NADP+

P

ADP

i

+

ATP

NADPH

O2

Calvin

Cycle

CO2

Slide 27

Light

Fig. 10-5-4

H2O

Chloroplast

Light

Reactions

NADP+

P

ADP

i

+

ATP

NADPH

O2

Calvin

Cycle

CO2

[CH2O]

(sugar)

Slide 28

Concept 10.2: The light reactions convert solar energy to the chemical energy of ATP and NADPH

Chloroplasts are solar-powered chemical factories

Their thylakoids transform light energy into the chemical energy of ATP and NADPH

Slide 29

The Nature of Sunlight

Light is a form of electromagnetic energy, also called electromagnetic radiation

Like other electromagnetic energy, light travels in rhythic waves

Wavelength is the distance between crests of waves

Wavelength determines the type of electromagnetic energy

Slide 30

The electromagnetic spectrum is the entire range of electromagnetic energy, or radiation

Visible light consists of wavelengths (including those that drive photosynthesis) that produce colors we can see

Light also behaves as though it consists of discrete particles, called photons

Slide 31

UV

Fig. 10-6

Visible light

Infrared

Micro-

waves

Radio

waves

X-rays

Gamma

rays

103 m

1 m

(109 nm)

106 nm

103 nm

1 nm

10–3 nm

10–5 nm

380

450

500

550

600

650

700

750 nm

Longer wavelength

Lower energy

Higher energy

Shorter wavelength

Slide 32

Photosynthetic Pigments: The Light Receptors