Photosynthesis

Chloroplast

Draw, label and function Stroma Thylakoid Thylakoid membrane Granum Chlorophyll

Mesophyll tissue

Draw, label and function Stomata Mesophyll Lower/upper epidermis cuticle

Solar energy 42% of solar radiation passes through

atmosphere and reaches the surface Visible light – used in vision and

photosynthesis, makes up most of 42% Pigments (photons) absorb certain

wavelengths of light – absorption spectrum

Absorption/Action Spectrum

Chlorophylls a, b – absorb blue and red, reflect green (why look green) Carotenoids – absorb violet-blue-green, look yellowish

orange (see this in Fall leaves when chlorophyll breaks down

Spectrophotometer – measures amount of light that goes through a sample, calculates how much is absorbed.

Action Spectrum – use production rate of oxygen as a means to measure the rate of photosynthesis at each wavelength of light

photosynthesis

C.B. van Niel – oxygen given off comes from water, not carbon dioxide (1930)

Redox reaction 6CO2 + 6H2O (solar energy) yields C6H12O6 + 6O2 Carbon dioxide is reduced to a carbohydrate Water is oxidized to Oxygen

Reactions

1905 – F.F. Blackman – involves 2 reactions Light Reactions

Absorption of light in thylakoid membrane Electrons are energized and move down ETC Energy is captured, ATP production NADP+ is an electron carrier and becomes NADPH

Calvin Cycle reactions – Stroma Carbon dioxide taken up, reduced to carb. Use energy from ATP and NADPH which return to

light reaction to cycle again

Summary of Photosynthesis

Solar energy (sun) chemical energy (as ATP and NADPH) chemical energy (carbohydrate)

That’s ALL!!