Photosynthesis Flashcards
What is photosynthesis
The process by which plants using chlorophyll and sunlight make carbohydrates (mainly glucose) from CO2 and H20
What is the equation for photosynthesis
6 CO2(g) + 6 H2O(l) + LIGHT -> C6H12O6 + 6 O2(g)
What are the two major types of reactions that occur in photosynthesis
Light reactions (light dependant) and dark reactions (light INDEPENDENT)
What are light reactions
Light energy of the sun is trapped and channeled into forming the energy rich molecules called ATP (adenosine triphosphate) and NADPH (Nicotinamide adenine dinucleotide phosphate). Water is required and oxygen is a byproduct.
What are dark reactions
Often called the Calvin cycle. Uses the energy trapped in ATP to assemble CO2 and H2O into carbohydrates (mainly glucose). They DO NOT require light.
What are photosynthesis pigments
A pigment is a substance that absorbs light energy. Different pigments absorb different wavelengths of light. Any wavelengths of light that are not absorbed get reflected. The color of each pigment is determined by the particular wavelengths of light it reflects.
What is chlorophyll A
The main pigment of photosynthesis. Directly involved in photosynthesis in the conversion of light energy into chemical energy. Chlorophyll A reflects green, giving plants a green color
What are accessory pigments
They assist chlorophyll A in capturing light energy. They broaden the spectrum from which light energy can be absorbed and used for photosynthesis. They all absorb light energy and transfer it to the chlorophyll
What are the accessory pigments
Chlorophyll B, Xanthophylls, and Carotenes
What color does each of the accessory pigments reflect
Chlorophyll B - reflects green
Xanthophylls - reflects yellow
Carotenes - reflects orange
Where does photosynthesis occur
Occurs in the chloroplast of plant cells. Each chloroplast has a double membrane. The outer membrane forms a continuous outer boundary and the inner membrane is folded to form a stack of disk like structures. Each structure is called a “thylakoid”. A stack of these is called a granum/grana. The fluid filled space between the grana is called the stroma.
Where do light reactions occur
On the thylakoids
Where do dark reactions occur
In the stroma
