Photosynthesis 2.8 U2 Flashcards
Why is photosynthesis important?
Not only does it capture energy from outer space (the Sun) and convert it into compounds that all life on Earth can use…
… but it also produces oxygen, for aerobic organisms to breathe/use!
What is photosynthesis?
Uses energy from sunlight to convert water and carbon dioxide (low energy reactants) into sugar and oxygen (high-energy products)
These sugars can then be used to produce complex carbohydrates (like starch) or provide energy for their cells to do work
(sunlight) + 6CO2 + 6H2O —> C6H12O6 + 6O2
What organisms conduct photosynthesis?
Plants, algae, and cyanobacteria
What is the chloroplast?
Where photosynthesis takes place
Found in plants and other organisms (not animals)
Contain chlorophyll
What is stroma?
Fluid inside of chloroplast(kinda like cytoplasm)
What is granum?
Stack of thylakoids
What are thlakoids?
Where light-dependent reaction happens
What is chlorophyll?
A pigment that absorbs certain wavelengths and reflects others
What are the types of chlorophyll found in plants? What light do they reflect/absorb?
Two types found in plants, chlorophyll a and b
These REFLECT green light, which is why plants look green!
Thus, they ABSORB light that isn’t green, especially blue/violet and red light
What are the phases of photosythesis?
Light-dependent reactions and Calvin Cycle
Where does the light-dependent reaction occur?
In thylakoid
What is the light dependent reaction?
Sunlight absorbed, energy produced converts NADP+ and ADP into NADPH and ATP
Water is required (source of electrons and hydrogen atoms)
Oxygen is released
What is a photosystem?
clusters of chlorophyll (light absorbing pigments ) and proteins in the thylakoid
What is photosystem II
Absorbs light, excites electrons, those electrons get passed to an electron transport chain
What is photosystem I
After electrons pass through ETC, this photosystem uses light energy to reenergize the electrons, which are picked up by NADP+ and H+
