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!!