photosynthesis

• The light-dependent reactions of photosynthesis occur in the thylakoid membrane of the chloroplasts.
• Plants convert solar energy into food which is then consumed by animals.
• All the food we eat and the fossil fuels we burn are products of photosynthesis.
• With the destruction of entire forests every day, we reduce the number of plants available to reduce carbon in the atmosphere.
• Go Out and Thank a Tree!
• When animals eat plants and other animals, the original solar energy is passed along the food chain.
• Stomata are little pores in leaves that open and close to let oxygen out and carbon dioxide in.
• NADP+ can hold excited electrons (e-) charged from the light energy harvested by chlorophyll to become NADPH.
• Pigments in the thylakoid membranes form protein complexes called Photosystem I and Photosystem II, which harvest photons to charge up energy carrying molecules that will power the dark reactions.
• Dark reactions, also called the Calvin-Bensen-Bassham cycle or just Calvin Cycle, occur in the stroma of chloroplasts and fix carbon dioxide into glucose.
• P is a byproduct of photosynthesis not used by the plant so it is released through the stomata of plants.
• Chlorophyll absorbs all wavelength colors except green, which is reflected off giving plants their green appearance.
• Cyanobacteria are photosynthetic bacteria that undergo photosynthesis in lakes, ponds, and oceans.
• The Photosynthesis Reaction is divided into two parts: Dark reactions or “light independent reactions” do not need light energy to power their reactions and can occur day or night.
• ATP is the “cellular currency” because it is used to power all the reactions that take place in the cells of all living things.
• Chloroplasts are full of thylakoids stacked in granum.
• NADP+ is a very complex molecule, this is a simplification.
• The energy absorbed by the chlorophyll during the light reactions is used to power photosystem II that breaks the bonds of water absorbed through the plant’s roots.
• Light reactions or “light dependent reactions” capture light energy to power photosynthesis.
• Chlorophyll is a green pigment and is the most abundant.
• Freed oxygen atoms bind with each other to form the gas O2.
• The thylakoid membranes are lined by pigments such as chlorophyll and carotenoids, which harvest light energy packets or photons when they absorb sunlight.
• Cyanobacteria lack chloroplasts, which is why they cannot perform photosynthesis.
• Light reactions occur during the day time and take place in the thylakoids.
• Photosynthesis in plants happens in the chloroplasts.
• Deforestation is a contributing factor to the excessive amounts of CO2 in the atmosphere and is also due to human influence.
• Photosynthesis is carried out in two steps: first in two light dependent photosystems, and second in a light independent carbon fixation cycle called the Calvin Cycle.
• NADPH then carries its energy over to power the dark reactions or Calvin Cycle.
• Plants and animals use glucose to power metabolic processes.
• The rate at which human’s are burning fossil fuels is too high for plants and oceans to take carbon out of the atmosphere.
• Light reactions convert sunlight into ATP and NADPH.
• These protons are kept inside the thylakoid by the thylakoid membrane.
• Through this process, the plant is able to convert sunlight, water, and CO2 into glucose (or sugar) and ATP.
• Chloroplasts are the site of photosynthesis in plants.
• When there are more protons inside the thylakoid than in the stroma outside, protons want to leave the crowded thylakoid.
• The protein ATP synthase attaches a phosphate group to ADP (D = 2) making it ATP (T = 3).
• As a byproduct of this process, O2 is released.
• H+ protons cross the membrane to leave, a protein uses their passage to power ATP production.
• Plants are the producers of the biosphere creating the oxygen and glucose needed for most organisms.
• The dark reactions or Calvin Cycle uses ATP and NADPH to convert CO2 into sugar.