Ch. 7 - Photosynthesis

• refers to the light dependent reactions and synthesis to the putting together of sugar (the 3C sugar G3P) during the Calvin Cycle • all of our oil and gas originally from historic PS • PS organisms trap solar energy into ATP and NADPH which they use to drive the production of carbohydrates (a way to convert solar into chemical energy)

Organism that obtains energy from sunlight and carbon from CO2 by photosynthesis

Organism that cannot make its own organic food molecules and must obtain them from consuming other organisms or their organic products = a consumer or decomposer

• Glucose oxidized to CO2; oxygen reduced to water - CO2 reduced to glucose; H2O oxidized to O2

Found in interior of leaf; each cell has ~30-40 chloroplasts

Tiny pores used for gas exchange

Filled with thick fluid - stoma (Calvin Cycle here)

Contains pigments (light reactions here)

• light dependent reactions (thylakoids membrane): some ATP is produced via photophosphorylation and NADP+ is reduced is NADPH • Calvin Cycle

Nicotinamide adenine dinucleotide phosphate - same function as NAD+ in CR

• entire spectrum of radiation ranging in wavelengths form less than a nm to more than a km • shorter wavelength > higher energy • longer wavelength > lower energy

Last longer in the fall, after green chlorophyll molecules have been broken down = beautiful fall colours

Fixed quantity of light energy; the shorter the wavelength, the greater the energy

• When a molecule absorbs a photon of light, its electrons are boosted to a higher energy level • energy is quickly lost in the form of heat and light (longer, lower energy wavelength)

• Absorbs mainly blue-violet light and red light - looks blue-green because it reflects mainly green light

• absorbs mainly blue and orange light and reflects (and appears) yellow-green • broadens the range of light that a plant can use by conveying absorbed energy to chlorophyll a, which then puts the energy to work in the light-dependent reactions

• similar (but not identical to ETC in respiration) • are sets of light absorbing pigments and their associated electron carriers • consists of a number of light-harvesting complexes surrounding a reaction-centre complex

• in the thylakoids membrane light energy transfer between different pigment molecules to reach chlorophyll a • chlorophyll a passes on excited electron to a primary electron acceptor

contains various pigment molecules bound to proteins -function as a light-gathering antenna