Unit 4- Cellular Respiration & Photosynthesis Flashcards
Where does energy come from in the cells?
Chemical Bonds or Chemical Gradients that store potential energy or from the sun
Everything cells do requires _____
Energy
Much og stored chemical energy comes in the form of ____, particularly_____
Sugars ; Glucose
Define Cellular Respiration
A process whereby cells harvest energy from food molecules, usually by breaking fown sugar to CO2 and H2O
What are the molecules that usually provide cells with energy for cellular respiration?
Glucose, Fatty Acids, Proteins
Define: Activated Carriers
Portable sources of energy that fuel Biosyntesis (ATP, NADH)
Energy released from high-energy bonds of sugars is often captured in other high energy chemical bonds of what molecules?
Activated Carriers
What type of process is Cellular Respiration (Anabolic/Catabolic)
Catabolic (breaking down molecules)
Cellular Respiration is a _____ Process; It occurs in a series of small reactions.
Stepwise
What is a benefit of Cellular Respiration being a Stepwise process?
It allows cells to harvest energy at many steps while the food molecule is being degraded.
What are the two ways Animal Cells make ATP?
Substrate-Level Phosphorylation and Oxidative Phosphorylation
Define: Substrate-Level Phosphorylation
Breakdown of one substrate of enzyme powers that enxyme to add inorganic Phosphate to ADP (Makes ATP)
Define: Oxidative Phosphorylation
Production of ATP powered by the Electron-Transport System
When do both of the two ways cells make ATP occur?
During Cellular Respiration
Define: Catabolism
Process of breaking down food molecules into smaller molecules, releasing energy to generate activated carriers.
What are the 3 major steps of Catabolism?
Digestion
Generation of Acetyl CoA
Complete Oxidation of Acetyl CoA
Where does digestion take place?
Outside cells (Lumen of intestine) or in lysosomes
How are larger molecules broken down?
Into constituent building blocks (amino acids, fatty acids, sugars, etc.)
Where does the digestion continue after the Lumen of the intestines
The building blocks enter the cytosol for the next step.
Where does the generation of Acetyl CoA occur?
It partially occurs in the cytosol/matrix
How many pyruvates are generated during Glycolysis?
2 Pyruvates for 1 Glucose Molecule
Each pyruvate enters the Mitochondrial Matrix where it’s converted to what Molecule?
Acetyl CoA
How are fatty acids broken down?
They are broken down two Carbons at a time
How many acetyl CoA molecules are generated from each carbon of a fatty acid?
1 Acetyl CoA is generated for every two carbons
True or false: breakdown of Glucose and Fatty Acids both generate high energy Electron carriers?
TRUE
Where does the complete oxidation of Acetyl CoA occur?
In the Mitochondria
What cycle do the Acetyl CoA molecules enter?
The Citric Acid Cycle
NADH molecules donate their electrons to _______ which harnesses the electron’s energy to drive Oxidative Phosphorylation to produce ATP
The Electron Transport Chain
What does the NADH to ETC transfer consume?
Oxygen (O2)
Where does Glycolysis occur?
In the Cytosol
Glycolysis produces _____ in the absence of ____
ATP; O2
One Glucose molecule produces what in glycolysis?
2 Pyruvates
2 Net ATPs
2 NADH
True or false: Glycolysis is a new or derived trait used for generating ATP?
False: This is likely an ancient process.
What is G3P
Glyceraldehyde 3-Phosphate
Energy is relased from the electrons as they fall down the _____ to make _____.
ETC; ATP
Once NADH delivers the electrons to the___, it becomes ____ again, supplying NAD+ to meet the demands of ____ in the ______
NAD+; Glycolysis; Cytosol
What happens if NAD+ is not regenerated?
Respiration will Cease.
What is fermentation?
The process that allows glycolysis to continue in the absence of O2 by recycling cytoplasmic NADH back to NAD+ so that a small amount of ATP can be produced.
True or False: In the absence of O2 and fermentation occurring, other respiratory pathways can still function.
False: all other respiratory pathways are shut down in
absence of O2
What would occur if cytoplasmic NAD+ was not recycled for fermentation to occur?
No ATP would be produced, resulting in the organism’s death.
In fermentation, where do Pyruvate and NADH stay?
In the Cytosol
During fermentation, electrons from NADH are put back onto _____ or a break-dowhn product of it.
Pyruvate
The direct addition of Electrons tp puruvate produces?
Lactic Acid/Lactate
An Addition of electrons to pyruvate after it has lost one Carbon in the form of CO2 produces what?
Ethanol (Alcohol Fermentation)
Lactic Acid fermentation and Alcohol Fermentation both result in what?
Regeneration of NAD+ so Glycolysis can continue
Several small organic molecules are coverten to Acetyl CoA in the mitochondria, including _____ and _____
Pyruvate and Fatty Acids
What are the 3 Reactions that the Pyruvate Dehydrogenase Complex performs?
Decarboxylation (Removal of Carboxyl group in form of CO2
Formation of NADH using NAD+ and Electrons from Pyruvate
Generation of Acetyl Coa (Addition of CoA)
Fatty Acids are first activated by ___ to CoA, then trimmed 2__ at a time, with each two ___ eventually forming ______
Linkage
Carbons
Carbons
Acetyl CoA
NADH and FADH2 are generated for every _____ formed
Acetyl CoA
Where does generation of Acetyl CoA occur?
In the Mitochondrial Matrix
What is Acetyl CoA generated from?
Sugars and fats. Acetyl CoA readily enters the Citric Acid Cycle.
Sugars are readily converted to glucose or intermediates of ______
Glycolysis
How are Amino Acids processed in the Citric Acid Cycle?
They can be converted into various intermediates of the Citric Acid Cycle in the Mitochondrial Matrix
Sugars, Fats, and Proteins can all feed into _____ Pathways
Catabolic
The Citric Acid Cycle Oxidizes _____
Acetyl Groups
The _____ from Acetyl CoA enter the Citric Acid Cycle
Acetyls
What is released as a waste product of Acetyl group Oxidation?
CO2 is released as a waste product
The Citric Acid Cycle Requires ____ Indirectly
O2
NAD+ must be regenerated, otherwise it would all be trapped in the form of _____.
NADH
If the NAD+ is trapped as NADH, what would occur?
NADH cannot accept Electrons from the Citric Acid Cycle, resulting in a halt of the cycle.
The Acetyl group is transferred from a CoA to a 4-C compound _____,
Oxaloacetate
Oxaloacetate transfer generates ______ _____ a 6-C compound
Citric Acid (Citrate)
By the end of the Citric acid Cycle, Oxaloacetate will be
Regenerated
The Citric Acid Cycle generates _ NaDH Molecule(s)
3
The Citric Acid Cycle generates _ FADH MOlecule(s)
1
The Citric Acid Cycle generates ___ GTP Molecule(s)
1
1 GTP Molecule is approximately equivalent to 1 ____ molecule
ATP
What product is produced as waste in the citric acid cycle? How many are produced?
CO2; 2 Molecules
Oxidative Phosophorylation
Electrons carried by NADH and FADH2 are delivered to the Electron Transport Chain (ETC)
What is the Electron Transport Chain?
A Series of electron carriers embedded in the inner mitochondrial membrane (Plasma Membrane of Prokaryotes)
AS Electrons are passed from carrier to carrier, energy is ____ in the Electron Transport Chain
Released
Electrons lose energy as they ____ the ETC.
Move down or Fall down the ETC.
Energy is used to pump ____ across the mitochondrial membrane into the intermembrane space, generating a ____ Gradient that can drive ATP Production
Protons (H+); Proton Gradient
How Many ATP are generated via the ETC?
~26-28 ATP
What does O2 do in the ETC?
O2 “pulls” electrons down the ETC, being eventually reduced to H2O
Cells must regulate energy _____/_____ in order to function when energy supplies are scarce
Usgage/Storage
What do the control mechanisms regulate in metabolism?
They regulate which pathways particular metabolites will enter
What are the key components of the control mechanisms in metabolism?
Enzyme regulation (Both Positive and Negative)
Gluconeogenesis
When fasting or undergoing intense physical exercise, glucose reserves cannot be replenished fast enough. Gluconeogenesis can function to replenish glucose stores
Gluconeogenesis is essentially the reverse of what process?
Glycolysis
What energy cost is associated with Gluconeogenesis?
4 ATP and 2 GTP
Gluconeogenesis is the formation of Glucose from what molecule?
2 Pyruvate molecules
How does the cell determine if it will undergo Glycolysis or Gluconeogenesis?
Enzyme regulation determines which process is favored.
Phosphofructokinase is involved in what process?
Gluconeogenesis
Phosphofructokinase is regulated ______by feedback mechanisms
Allosterically
Phosphofructokinase is activated by
ADP, AMP, and Pi(Inorganic Phosphate)
Phosphofructokinase is inhibited by
ATP
Fructose 1,6-Bisphosphate is involved in what process?
Glycolysis
Fructose 1,6-Bisphosphate Is _____ regulated by feedback mechanisms
Allosterically
Fructose 1,6-Bisphosphate is regulated in the opposite manner as ______
Phosphofructokinase
Fructose 1,6-Bisphosphate is activated by
ATP
Fructose 1,6-Bisphosphate is inhibited by
ADP, AMP, Pi (Inorganic Phosphate)
What is Glycogen?
A polymer of Glucose, storage from of Glucose in Animals
Where is Glycogen found in Animal Cells?
Found in all cells, but large stores are in liver and muscle cells.
Production of Glycogen is regulated according to ____
Need
If ATP demand is high, glycogen is ____ to ____
Broken Down; Glucose
What breaks down Glycogen into Glucose?
Glycogen Phosphorylase
If ATP demand is low, Glycogen is ____ from _____
Produced ; Glucose
What produces Glycogen from Glucose?
Glycogen Synthetase
Electron Transport is a key process of what important pathways?
Photosynthesis and Cellular Respiration
The Majority of APT is generated by ____ ____ ____ _____
Membrane-Based Oxidative Phosphorylation
True or False: Oxidative Phosphorylation could not occur without a membrane
TRUE
In oxidative phosphorylation, electron transport
along membrane facilitates
generation of______ gradient across that membrane
H+ (Proton)
Where does Oxidative Phosphorylation occur in Eukaryotes?
It occurs along the inner Mitochondrial Membrane, creating a high Proton concentration in the intermembrane space and a low Proton concentration in the Mitochondrial Matrix
In Photosynthetic Eukaryotes, where does Oxidative Phosphorylation occur?
It occurs in the thylakoid membranes, creating a high Proton concentration inside the Thylakoid (Thylakoid Space) and Low Proton Concentration in the Stroma
Define the ETC:
High-Energy Electrons transferred along electron carriers embedded in the membrane release energy to proteins of chain to pump Protons across the membrane and thus generate the Proton Gradient
Define: Chemiosmotic Coupling
Proton flow down the Electrochemical gradient through the ATP Synthase wihch synthesizes ATP from ADP and Pi
Membrane-Based energy harvesting is present in which domains? What does this indicate?
It is present in all domains, indicating it evolved long ago in early life
What is the function of the Mitochondria?
Provides the bulk of usable energy in the cell
How many ATP are generated in the Mitochondria?
~30 from one molecule of Glucose
True or False: Complex multicellular organisms would likely have not evolved without the Mitochondria
True: There is a lot of energy required for a multicellular organism to function
True or False: Mitochondria are restricted to their initia size, location, and number
FALSE: Mitochondria resemble their prokaryotic ancestors and are remarkably adaptable: They can change size, location, and number
Some cells ____ Mitochondria to areas where they’re most needed
Localize
What areas of the cell would require more Mitochondria?
Contractile Apparatus in muscle cells or flagellum in sperm
Mitochondria can fuse into giant, _______ networks
Dynamic (Changing)
Mitochondria can ____ if needed ex. In Muscle cells after that cell has been contracted repeatedly
Increase in number/size
Outer Membrane of the Mitochondria
Smooth, surrounds all other components, contains porins
Porins (in the Mitochondria)
Large, Aqueous pores that allow diffusion of relatively large molecules into the intermembrane space
Inner Mitochondrial Membrane
Highly convoluted (Cristae), site of Oxidative Phosphorylation, contains transport proteins that get molecules in/out of matrix (Pyruvate, Fatty Acids)
Intermembrane Space
Site where Protons Build up; similar to the cytosol due to porins in the outer membrane
Mitochondrial Matrix
The Large innermost space of the Mitochondria. Site of the Citric Acid Cycle and Fatty Acid breakdown, impervious to ions and small molecules unless a path is provided. Therefore, contents are highly specialized.
The Citric Acid Cycle
Generates high-Energy Electrsons that power ATP Production
The Fuel for the citric Acid Cycle comes from
Pyruvate and Fatty Acids
In the Citric Acid Cycle, both pyruvate and fatty acids enter the membrane via____ in the outer membrane and then get transported into the ____
Porins
Matrix
In the Matrix, Pyruvate and Fatty Acids are broken down into _____ and enter the ___ _____ ___
Acetyl CoA
Citric Acid Cycle
In the Citric Acid Cycle, Acetyl CoA is _____ to CO2 and their high energy electrons are temporarily stored in activated carriers ____ and _____
Oxidized
NADH
FADH2
NADH and FADH2 donate their electrons to the ____, becoming ____ and ____
ETC
NAD+
FAD
Electrons are passed down the chain to ____ forming ___ in a fast, stepwise process
O2
H2O
Each step of H2O formation releases some ___ the electrons carry
Energy
Part of the energy released in the formation of H2O form O2 isused to do what?
Pump H+ (Protons) into the intermembrane space
Electron movement down the ETC converts energy from electrons into ____ energy in the electrochemical gradient which will ultimately be used to ______
Potential
Make High-Energy bond in ATP
What is the source of High-Energy Electrons for Catabolism?
Sugars and Fatty Acids
What is the source of High-Energy electrons for Anabolism?
Excited Electrons from Chlorophyll
What is the source of High-Energy Electrons for Anaerobically respiring Organisms?
Inorganic Substances (Iron, Sulfur, Hydrogen)
True or False: The ETC is present in many copies along the inner membrane.
TRUE
The ETC is composed of over __ proteins grouped into ___ large respiratory enzymen complexes.
40
3
What are the 3 large respiratory enzyme complexes in the ETC called?
NADH Dehydrogenase Complex
Cytochrome C Reductase Complex
Cytochrome C Oxidase Complex
Oxidation is a ___
Loss of Electrons
Reduction is a __
Gain of electrons
As electrons move through the 3 complexes, ____ are pumped across the _____ into the ______ _____
Protons (H+)
Inner Membrane
Intermembrane Space
NADH Dehydrogenase complex accepts electrons from ______
NADH
NADH Dehydrogenase complex accepts electrons from NADH which is extracted as a ___ Ion which is converted to
H-
2e-+ H+
After NADH Dehydrogenase Complex accepts the electrons from NADH, what happens next?
Electrons are passed to the next members of the chain.
Electron transfer is energetically ____ since each acceptor has a stronger _____ _____ than the donor that’s passing the electron off
Favorable
Electron Affinity
What is the Final Electron acceptor in the ETC? What occurs with this?
O2
electrons are combined with O and H+ to generate H2O
Proton Motive Force
Energy is released from energetically favorable passage of electrons from ETC member to ETC member is trapped in the form of H+ Electrochemical gradient across the inner membrane
Each Respiratory Complex of the ETC pumps ___ across the membrane as ___ are transferred
H+(Protons)
Electrons
What is the pH of the mitochondrial Matrix?
~7.9
What is the pH of the intermembrane space of the mitochondria?
~7.2
There is a voltage gradient due to the excessive positive charge ___ of the matrix; therefore the matrix face of the ___ __ is ____ compared to the intermembrane space face
Outisde
Inner Membrane
Negative
Both Chemical and Voltage gradients favor movement of ___ (into/out of ) the matrix
H+
Into
H+ cannot diffuse through the mambrane, nor are there any ___ channels present that permit this.
ION
The Proton Motive Force
Both chemical and voltage gradients favor
movement of H+
into matrix; however, H+ cannot
diffuse through membrane, nor are there any ion
channels present that permit this
H+ can only move back into the matrix via
ATP Synthase
What is the ATP Synthase
Large, Multisubunit protein complex embedded in the inner membrane
As H+ moved down their EC gradient, they power ____ to combine ____ and ____ to form _____
ATP Synthase
ADP+Pi
ATP
ATP Synthesizing part resembles a ____ with its head int he matrix and ___ carrier is embedded in the membrane and has a stalk that is embedded in the ATP Synthesizing _____
Lollipop
H+
Head
ATP movement through the carrier in the ATP Synthase cause the carrier and its ____ to _____
Stalk
Spin
As the Stalk in the ATP Synthase rotates, it rubs against stationary ____ in the ___ region, changing their conformations
Proteins
Head region
The Mechanical deformation cause by the rotation in the stalk of the ATP Synthase is converted into a high energy bond in
ATP
How many molecules of ATP are produced per rotation of the ATP Synthase?
3
In addition to ATP Synthesis, the Proton gradient is used to power transport of _____ across the _____
Molecules
Inner Membrane
Symporters move ____ ___ and ___ into the matrix
Pyruvate
ADP
Pi
Antiporters move ATP ___ and ADP ___ using H+ EC gradient to power the process.
ATP (Out)
ADP (In)
ADP is quickly returned to the ______ due to activity of the ATP/ADP ____
Mitochondria
Antiporters
The ATP/ADP Antiporters help quickly recharge ADP that have been produced as a result of ____ ____ ____
Normal Cell Activities
The quick recharging of ATP/ADP keeps cells at a ratio of __ ATP to __ ADP
10 ATP to 1 ADP
Efficiency of Respiration is ___ due to several small reactions resulting in release of small amounts of ____ at a time
High
Energy
True or False: Cellular Respiration Allows large amount of energy from food to be parceled out to small packets whose energy can be easily and efficiently captured by cell in form of activated carriers, i.e NADH, FADH2, ATP
TRUE
1 NADH powers production of __ ATP
2.5 ATP
1 FADH powers production of __ ATP
1.5 ATP
How much of energy in glucose is converted to ATP?
~50%
H+ can move readily through aqueous environments by rapidly dissociating from one H2O and and associating with
its neighboring H2O
True or False: Proton movement includes not just free H+ but also H+ that are part of water molecules; thus, water is serves as resevior for H+ to be moved across
inner membrane
TRUE
H+ often accompany ____ during redox reactions.
Electrons
An Addition of negative charge associated w/ Electrons on the reduced moledule is immediately neutralized ____ donated from water
H+
During Oxidation, ____ Accompanying H+ is added to water
Electrons
Transferability of H+ from /to water makes it so that as long as electron carrier is oriented in the membrane such that it has contact with ___ sides, it can easily pass ___ from one side to the other.
Both
H+
electrons are readily passed from atoms that have ___ affinity for electrons in their outer shell to atoms with ____ e- affinities in their outer shell
Low
Higher
NADH’s atoms have lower electron affinity than NADH Dehydrogenase Complex’s atoms; Thus NADH’s electrons are readily passed to complex, forming___
NAD+
All Redox reactions occur in ____ w/ one member Losing electrons and another gaiing electrons
Pairs
What is an example of a Redox reaction?
NADH/NAD+
Redox Potential:
Tendency of redox pair to donate/accept electrons
Eletrons from redox pair w/ low affinity for electrons to pair w/ high affinity for electrons is a spontaneous ___ and thus _____ energy
(-ΔG)
Releases
Metal atoms are tightly bound to proteins of the _____
ETC
Electrons move within a single complex by skipping from one metal atom to the next with each successibe metalion having a higher _____ ____ than the previous ion.
Electron Affinity
Between ETC Complexes, electron carriers that diffuse freely within the ____ ____ ____ transport electrons
Inner Mitochondrial Membrane
Ubiquinone transfers electrons from ____ ____ ____ to ____ ____ ____
NADH dehydrogenase complex
Cytochrome c reductase
Ubiquinone accepts electrons from
FADH2
Besides Oxygen, what is the final member of the ETC?
Cytochrome c oxidase
Cytochrome C OXidase transfers 4 electrons to ___ which has a high affinity for electrons
O2
Cytochrome C Ocidase has Cu2+ ion and heme group at active site that helps it hold ___ in place until all ___ have been added
O2
Electrons
If it could not hold O2 in place, Oxygen radicals would be produced which steal electrons from various biomolecules, thus _____ Cells.
Damaging
In Cytochrome C, 2 H+ are added and ___ ___ are formed
2 H2O
What is the process that is responsible for producing (Almost) all organic material on Earth
Photosynthesis
Photosynthesis creates organic sugars from inorganic, atmospheric ____.
CO2
Photosynthesis uses electrons from ___ and energy from ___.
H2O
Sunglight
O2 from ___ is a waste product and support oxidative Phosphorylation during respiration
H2O
Photosynthesis is performed by what organisms?
Plants, Algae, and Photosynthetic Bacteria (Chloroplasts in plants)
Chloroplasts are similar to mithchondria but are ___ have have extra ___ ___
Larger
Internal Compartment
The outer and inner membranes with similar_____ to their mitochondrial counterparts
Permeabilities
Sugars are made in the ____
Stroma of the Chloroplast
Thylakoids
Membranous, disc-like interconnected stacks in the stroma
Thylakoids found in stacks are called
Grana / Granum
Interior of Thylakoids are called the
Thylakoid space
Energy from light is harvested along the
Thylakoid membranes
What are the two most important players in Photosynthesis?
ATP and NADH
ATP and NADH connec the __ part to the ___ part
Photo
Synthesis
What are the two stages in Photosynthesis?
The Light Reactions and the Carbon- Fixation Reactions
What occurs in the Light Reactions:
The ETC in the Thylakoid membrane harnesses energy from light to pump H+ across thylakoid membrane into the thylakoid space
Electrochemical gradient used to make ATP via ________ ________
embedded in the membrane
ATP Synthase
How is the Light reaction Different from oxidative phosphorylation?
high
energy e- come from light-excited chlorophyll
In the Light Reactions of Photosynthesis, Excited e- end up associated with activated carrier _____ at end of this stage
NADPH
ATP and NADPH produced in Stage 1 of Photosynthesis drive production of sugars from _____
Specifically _____
CO2
G3P
What is G3P?
Glyceraldehyde 3 Phosphate
True or False: The Carbon Fixation reactions can occur in the light only.
True: It can occur without light, but it doesn’t occur naturally
Chlorophyll
A pigment that absorbs light at specific wavelengths (blue to red) and reflects light of other wavelengths (green)
electrons of chlorophyll hover in ____ above light absorbing porphorin of molecule
Clouds
When the light of specific wavelength hits chlorophyll,
these electrons become ____, altering their distribution
excited
When electrons are altered and chlorophyll hits the light, what happens?
This destabilizes the molecule, which will then
seek to get rid of this excess energy so it can
return to their unexcited state
Chlorophyll in thylakoid membranes are held in large,
multiprotein complexes called __________
Photosystems
Photosystems are composed of ___ ___ and ____ ____
Antenna Complexes
Reaction Center
Antenna Complexes capture
Light Energy
In an Antenna complex, Hundreds of chlorophyll molecules arranged so that energy captured by
_____ gets _____ to its neighbor
One
Transferred
In an Antenna Complex, Eventually, energy arrives at ____ ____ of chlorophyll molecules which holds its electrons in lower energy state than others, trapping energy there
Special Pair
Reaction center converts
light energy into chemical energy
the reactions center is a complex associated with the _____ ____
Special Pair
The reaction center has electrons poised to accept _____ _____ _____ from the special pair
High-Energy Electrons
When the reaction center accepts high-energy electrons, this is the point where light energy is converted into____ ____
Chemical Energy
When the special pair passes off the electrons, it becomes positively charged and the electron acceptor becomes ____ ____
Negatively Charged
The charge separation of the Special pair initiates a flow of electrons from the acceptor to the
electron transport chain.
In order to make sugar (in the ___ ___ cycle), the cell requires much energy ____ ad reducing power _____
Carbon Fixation
ATP
NADPH
There are __ Photosystems which are involved in the light reactions and use high-energy electrons
2
Photosystem II
Functions first,
Passes energized electrons from special pair to the Plastoquine
What is the Plastoquine?
It passes the electrons to the ETC, which umps H+ across the Thylakoid space
How is the H+ gradient used in Photosystem II?
It is used to drive ATP Synthesis as occurs in respiration
Photosystem I
Functions while Photosystem II functions
How does Photosystem II function?
It passes excited electron from its special pair to ferredoxin
What is Ferredoxin?
Carries electrons to the Ferredoxin-NADP Reductase (FNR)
FNR transfers electrons to _____, reducing it to ____
NADP+
NADPH
Photosystem II Splits
Water
When electrons leave the Special Pair Chlorophyll , it leaves behind a _____ charge on Chlorophyll
Positive
Photosystem II has a water-splitting enzyme that removes electrons from ____ One at a time
H2O
Once four electrons have been given to 4 special pairs that have lost their electrons, the enzyme releases _____
O2
The enzyme waits for 4 Electrons, ensuring dangerously reactive ___ molecules are not released.
H2O
Photosystem I receives electrons from _____ ____
Photosystem II
Photosystem ___ serves as the final electron acceptor of the ETC initiated by _____ ____
I
Photosystem II
The Flow of electrons during the light reactions:
PSII->Plastoquinone->Cytochromeb-6-f Complex
->Plastocyanin->PSI->Ferredoxin->FNR->NADPH
NADPH and ATP from the light reactions are produced in the _____
Stroma
True or False: ATP and NADPH from the light reactions can leave the chloroplast.
False: They cannot leave the chloroplast
The Carbon Fixation Cycle
Provide energy and reducing power to make sugar in stroma from CO2 and H2O (carbon fixation)
In Carbon Fixation, Rubisco attaches ___ to ribulose 1,6 Bisphosphate (5C sugar) yielding two _____
Rubisco
3-Phosphoglycerate
Rubisco
Ribulose Bisphosphate Carboxylase
Rubisco is “Slow” so plant cells have many copies of it around so more _____ Can be fixed
CO2s
What is the most abundant protein on earth?
Rubisco
All reactions that function in the carbon fixation are known as
The Calvin Cycle or Carbon Fixation Cycle
For every 3 CO2 molecules that enter the Calvin Cycle, one ___ is produced
G3P
The Calvin Cycle consumes ___ ATP and ___ NADPH
6
9
When G3P is present in excess, (When photosynthesis is occurring frequently), it can be stored as ____ or ___ in the ____
Starch
Fat
Stroma
At night, Starch and Fat are broken down and energy is ___ via ___ ___ to drive plant cell function
Released
Cellular Respiration
G3P can be used to make ___which can be transferred to other cells of plant, providing them energy they need to function
Sucrose
Sucrose is a (What type of molecule)
Disaccharide
