photosynthesis overview.notebook
October 03, 2013
PHOTOSYNTHESIS OVERVIEW
Producers- type of organism that produces their own chemical
energy in order to stay alive (mainly plants)
-Provide most organisms on Earth with their energy
-happens directly- animals eat the plants
-happens indirectly- animals eat other animals that
eat plants
-The tissues in organisms are built from its food
source (sugars and other carbon-based molecules)
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photosynthesis overview.notebook
October 03, 2013
ALL energy begins with the sun.
Photosynthesis- process that captures energy from sunlight to
make sugars that store chemical energy
-Chlorophyll (green pigment containing part of a
chloroplast) absorbs the energy in visible light
-Visible light is made up of the colors of the rainbow
-It is mostly reds and blues that are absorbedmost greens are reflected, so plants appear
to
be
green.
-Takes place in chloroplasts, more chloroplasts in leaf cells
-Two main parts: grana and stroma
a. GRANA (granum) - stacks of coin-shaped
membrane enclosed copartments called
thylakoids.
-thylakoids contain chlorophyll and proteins
b. STROMA -fluid that surrounds grana inside
chloroplasts
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photosynthesis overview.notebook
October 03, 2013
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photosynthesis overview.notebook
October 03, 2013
*2 Steps to Photosynthesis: Light dependent reactions &
Light independent reactions
PART A: Light dependent reactions
*Job is to capture Energy from the sun
*Takes place in thylakoids
*Water and sunlight are needed
PROCESS:
1. Chlorophyll absorb energy from the sun
2. Water molecules are broken down
3. Oxygen is released
4. Energy-carrying molecules, including ATP, transfer
energy along the thylakoids
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photosynthesis overview.notebook
October 03, 2013
Part B: Light Independent Reactions
*Job is to use the energy from the light dependent to
make sugars.
*Takes place in stroma
*Carbon dioxide is needed
PROCESS:
1. Carbon dioxide molecules are added to the cycle to
build larger sugar molecules.
2. Simple sugars are formed, usually glucose (C6H12 O6)
-stores some Energy captured from the sunlight
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photosynthesis overview.notebook
October 03, 2013
A simple equation shows us the reactants (what went into
photosynthesis-ingredients) and the products (what comes
out of photosynthesis)
-Arrow points in the direction of the products
Sunlight + 6CO2 + 6H2O -> C6H12 O6 + 6O2
Sunlight + Carbon dioxide + water -> glucose + oxygen
-Must keep in mind that enzymes and other chemicals
aid in the overall reaction, they are just not
represented in the equation.
-Simple sugars like glucose are not the only things to
come out of photosynthesis as plants need other
materials for growth and development.
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photosynthesis overview.notebook
October 03, 2013
Figure in book
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