PHOTOSYNTHESIS What do you know? What do you want to know?
Post on 28-Dec-2015
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What do you know?
What do you want to know?
Photosynthesis uses sun energy to make sugar (glucose) (Plants and algae only Autotrophs- make their own food Heterotrophs- cant make their own food
All living organisms ( including plants) use cellular respiration to get energy from their food
Photosynthesis EQUATIONReactants- light , carbon dioxide, & waterProducts: sugar and oxygenSunlight+6CO2+ 6H20 C6H12O6 + __O2
Light & Pigments
Sunlight is white but contains mixtures of visible wavelengths
Chlorophyll is a PIGMENT in the chloroplast of the plant cell that absorbs light
Leaves absorb blue-violet & red-orange light very well - Green light is reflected- why plants look green!
MajorPigments MinorPigments Types of Pigments
Chlorophyll a Absorbs all colors of light except green Plays major role in light reactions of photosynthesis Chlorophyll b Appears yellow-green Absorbs additional lightXanthophyllYellow pigment CaroteneRed & orange pigments
LOCATION OF PHOTOSYNTHESISChloroplasts organelle in plant cells
** Chloroplast has double membrane **
Thylakoids: sac-like photosynthetic membranesArranged in stacks called GRANAHave chlorophyll and other pigments Stroma: Fluid area surrounding thylakoidsCHLOROPLAST STRUCTURE
Boozeman 5:00 Minutes
* Light-Dependent: takes place in thylakoids-
* Calvin Cycle: takes place in stroma
Light ReactionChlorophyll molecules in thylakoid capture light energyThis energy releases electrons from H2OH2O then splits into O2 and H+ Oxygen is a "waste product" & escapes to the atmosphere
So what happens to the electrons and hydrogen ions?Chloroplasts use them to make an energy-rich molecule called NADPH and ATP
The overall result of the light reaction?Light + H20 Oxygen + NADPH + ATPLight Reaction
Light reaction is charging up the battery needed to synthesize sugars in Calvin Cycle
- ADP and NADP+ recycle
Calvin CycleDoes NOT use light at allCan use energy that was made in light cycle to form sugar
Occurs in the STROMA.
Uses CO2 and energy powered by ATP and NADPH to produce sugar
NAPDH and ATP are recycled back to the Light Cycle for rechargingThe Calvin Cycle
Two ProcessesLight ReactionCalvin Cycle
Online Activity 8.1- Animation of Light and Dark Cycles
Page 6 Start
Factors Affecting PhotosynthesisTemperatureLight intensity
**Next slide equation **Did we see chlorplasts in the onion? Why not!!! *****Chloroplast- many hang out in the middle of the leaves ( mesophyll )
**Print this for CP!! **4 steps *******