make their own energy
get energy from other organisms
Chloroplasts are found where?
mesophyll of leafs
interior tissue of leafs
Thylakoids are found where?
inside the chloroplast
Thylakoids do what?
help capture sunlight for plants
Thylakoids are arranged in stacks called _____.
Region of fluid filled space outside the thylakoids is the ______.
substances that absorb visible light
Chlorophyll transmitts _____ light, absorbs all others
There are other pigments such as __________ _ and _________ present in plants.
Chlorophyll B; carotenoids
Device that measures a pigment’s ability to absorb various wavelengths of light
How do spectrophotometers work?
sends light through pigments and measures amount of light transmitted
a graph plotting a pigment’s light absorption versus wavelength
The absorption spectrum of chlorophyll suggests that what type of light work best for photosynthesis?
violet-blue and red light
tells you which wavelength of light actually drives photosynthesis the best
Who made an action spectrum using algae and bacteria?
What do chloroplasts do with light?
use light photons to help take electrons from water
Where do the electrons taken from water go?
The electrons are then added to CO2 to make glucose
Photosynthesis is a _____ process in which H2O is oxidized and CO2 is reduced
To gain electrons
to lose elctrons
Light reaction requires _______.
Light reaction happens where?
In light reaction, what happens to water?
Water is oxidized
Light reaction produces ______ & ___.
The _________ ___________ contain photosystems.
pigment molecules attached to proteins that funnels light energy into a reaction center where electrons are transferred
The proteins that photosystems are attached to are what?
light harvesting complex
In photosystems, what happens with light? (Light Reaction)
Light comes in; electrons come out.
First step in photosystem II (Light Reaction)
Light first enters photosystem II
What happens when light enters photosystem II? (Light Reaction)
The light excites chlorophyll molecules, who excite other chlorophyll molecules by passing on photons.
What happens meanwhile light is entering photosystem II? (Light Reaction)
Water is split into hydrogen and oxygen by enzymes
What happens to the oxygen and hydrogen when the water is split? (Light Reaction)
The oxygen is released as waste. The hydrogen is kept.
P680 is named so why?
it prefers 680nm light
What is P680?
a special chlorophyll molecule in photosystem II that takes electrons from the hydrogen that came from the split water
Where do the photons being passed by the chlorophyll go? (Light Reaction)
They get sent to P680
What happens to P680 when it receives photons? (Light Reaction)
P680 gets so exited that it loses the electrons it received
Describe Primary Electron Acceptor (Light Reaction)
a molecule in the reaction center that
receives electrons from P680.
Describe linear flow (Light Reaction)
The primary electron acceptor sends the electrons down the electron transport chain (ETC) to Photosystem I
During linear flow movement of the electrons is used for what? (Light Reaction)
to make ATP
As electrons move, what happens? (ATP Production)
they cause the Hydrogens (protons) from water to move out of the membrane into the thylakoid space.
As hydrogens build up in the thylakoid space, what happens? (ATP Production)
they are forced back through the membrane through ATP synthase into the stroma.
enzyme that makes ATP as hydrogens pass through
Where does PI get its electrons? (Light Reaction)
from the ETC
____ in photosystem I is going to receive electrons coming from the ETC (Light Reaction)
What does light do in PI? (Light Reaction)
Light excites chlorophyll molecules in PI who excite other chlorophyll molecules by passing on photons
What happens when photons are sent to P700? (Light Reaction)
P700 who gets so excited that it loses the electrons it got from the ETC.
Describe cyclic flow (Light Reaction)
The primary acceptor can then send the electrons back to the top of the ETC so they call come down again and make more ATP
The _______ _______ _________ receives the electrons from P700 (Light Reaction)
primary electron acceptor
The primary acceptor in PI can also send the electrons to an electron carrier called _____ (Light Reaction)
How is NADPH created from NADP+? (Light Reaction)
Once NADP+ gets electrons to carry (gets reduced) it becomes NADPH
The NADPH will take electrons to the stroma to do what? (Light Reaction)
begin the second cycle
___ will also go to the stroma to help start the second cycle. (Light Reaction)
The synthesis part is photosynthesis is called?
What is another name for the Calvin cycle?
Where does the Calvin cycle take place?
Calvin cycle does what with CO2?
Calvin cycle needs what two key molecules made in Light Reaction?
Calvin cycle produces what?
What is the process called of incorporating Carbon dioxide (Calvin cycle Phase 1)?
The 5 carbon sugar in Phase 1-Step 1 of Calvin cycle is called what
Calvin cycle Phase 1-Step 1
An enzyme adds one CO2 to RuBP to make a 6 carbon sugar. (this happens three times)
enzyme adds one CO2 to RuBP to make a 6 carbon sugar is called
Calvin cycle Phase 1-Step 2
The 6 carbon sugar then splits into two 3 carbon molecules
What is Phase 2 of Calvin cycle
Calvin cycle Phase 2-Step 1
ATP is used to add a phosphate to the 3 carbon molecules (makes the molecule unstable)
Calvin cycle Phase 2-Step 2
NADPH then reduces the 3 carbon molecule, replacing the newly added phosphate with electrons
3 carbon molecule is now called ___. (Calvin Cycle Phase 2-Step 2)
What is Phase 3 of Calvin Cycle?
What is the point of regeneration of Phase 3?
Calvin Cycle Phase 3-Step 1
1 Molecule of G3P is sent out to make glucose
_ G3P’s make _ glucose
2 G3P’s make 1 glucose
Calvin Cycle Phase 3-Step 2
5 Molecules of G3P are used to make 3 RuBP. This starts over the Calvin Cycle
Describe C3 Plants
initial fixation of CO2, via rubisco, forms a three-carbon compound
Most plants are what type?
What do C3 plants do on hot, dry days
plants close stomata, which conserves H2O but also limits intake of CO2
What do C4 plants do on hot, dry days
counteract hot dry days by fixing CO2 into four-carbon compounds in mesophyll cells.
C4 requires the enzyme ___ _________ because it can fix CO2 even when there isn’t much of it.
It requires the enzyme PEP carboxylase because it can fix CO2 even when there isn’t much of it.
C4-The four-carbon compounds are send to ______-______ ____, where they release CO2 that is then used in the Calvin cycle
Goal of C4 plants
Increases CO2 for the calvin cycle when stomata are closed to save water
CAM plants do what?
Cam plants use CAM to fix CO2 into 4 carbon molecules
CAM plants open their stomata when?
Main process of CAM plants
Stomata close during the day, and CO2 is released from the 4 carbon molecules and used in the Calvin cycle