Ch.9 Flashcards
6H2O + 6CO2 + energy(photons) —–> C6H12O6 + 6O2
What process does the chemical equation describe?
Photosynthesis
Where does all the O2 of photosynthesis come from?
oxidation of water
In the photosynthesis chemical equation what does CO2 get reduced too?
Glucose
What causes algal blooms?
nutrients (usually phosphorus)
Temperature
Why can algal blooms be a problem?
Production of toxic compounds
Oxygen consumption by algae and bacteria feeding on dead algae
Where does photosynthesis take place in Eukaryotes?
Chloroplasts
Where does photosynthesis take place in prokaryotes?
Internally folded membrane
TF:
Atoms can absorb the energy of photons
T
TF:
Atoms can give off photons
T
TF:
Only certain atoms and molecules absorb certain types of photons
T
Which molecules absorb the photons?
Pigments
What is emitted after an electron leaves the higher energy state and returns to it’s original state?
Photon
What is the pigment involved in photosynthesis tha absorbs blue and red light?
Chlorophylls
What can absorb photons of wavelenths that chlorophyll can’t and passes the light energy off to chlorophyll?
Accessory pigments
Can pigments that chlorophyll can’t absorb be used in photosynthesis?
Yes
Two different stages in photosynthesis
Light reactions
Dark reactions
Why is the light energy transferred to electrons in light reactions of photosynthesis
To be used to make ATP and high energy electron source
What happens in Dark reactions
CO2 is reduced to a carbohydrate
What happens once the energy from electrons is directed towards cholorophyll
Energy of electrons in chlorophyll is increased and causes them to be lost from the chlorophyll molecule
In photosystem II what are the electrons lost from chlorophyll replaced with?
electrons from H2O
What are electrons passed down?
Electron transport chain
What happens to the H+ ions
Actively transported accross the membrane
Where are the H+ ions transported from and to
From the Stroma in to the thylacoid compartment
TF:
Photosystem II is involved in more than one process
F:
Photosystem II is only involved in ATP production
How does H+ pass back in to the stoma in Photosystem II?
ATP synthase
What happens to the electrons at the end of the electron transport chain of Photosystem II?
They are passed on to Photosystem I
What are the two paths that excited electrons can take?
Cyclic
Non cyclic
What happens to an electron that takes the cyclic path in Photosystem I
They travel through an electron transport chain back to photosystem I
What does the cyclic path produce?
ATP
What process does the cyclic path use to create ATP
Chemiosmosis
What happens to electrons in the Non cyclic path?
They are passed to an electron carrier
What is the electron carrier used in the non cyclic path?
NADP+
What are the 3 phases of the Dark Reactions
Carbon fixation
Reduction
Regeneration
What does carbon combine with in the carbon fixation phase?
5 Carbon sugar
What happens once carbon has attached itself to the sugar molecule?
It splits in to 2 molecules
In the reduction phase what are donated to 3 Carbon molecules and what donates them?
Electrons are donated from NADPH
In the reduction phase, what happens to one of the 3 carbon products?
Used to produce glucose
In the Regeneration phase, what happens to one of the 3 carbon compounds? And does it require energy? if so, what is the name of the energy required?
It is used to make a new RuBP, it requires ATP
What is the name of the Balance between light and dark reactions?
Photostasis
TF:
Organisms build photosynthetic systems to balance light and dark reactions
True
What happens to reaction centers in photostasis if they remain reduced?
They will be damaged
What reactions are temperature sensitive?
Dark reactions
What two measures can be taken to compensate for a change in temperature?
Change in pigment
Reduce their chlorophyll levels
What happens to plants when they take in CO2?
lose water
What part of the plant regulates gas exchange in leaves?
Stomata
TF:
The stomata prevents water loss
True
