HW04: Ch. 7 (Cellular Resp) and 8 (Photosynthesis)

Pay close attention to the carbon atoms, electron carriers, and ATP formation

(Glycolysis): During glycolysis, the glucose molecule is split in half and the molecule NAD+, an electron carrier, picks up electrons and hydrogen atoms For every one glucose molecule, 2 net ATPs are produced during glycolysis Glycolysis starts with 1 molecule of glucose and ends with two pyruvate (pyruvic acid) molecules, a total of 4 ATP molecules, and 2 molecules of NADH (Acetyl CoA formation) After glycolysis, as the pyruvic acid molecule enters the mitochondrion, one carbon is removed forming carbon dioxide as a by-product Electrons are stripped forming NADH Coenzyme A attaches to the 2-carbon fragment, forming acetyl CoA coenzyme A is removed and the remaining 2-carbon skeleton is attached to an existing 4-carbon molecule that serves as the starting point for the citric acid cycle (citric acid cycle): 2 carbons—from acetyl CoA—enter the citric acid cycle in each turn, and 2 carbon dioxide molecules are released Coenzyme A attaches to the 2-carbon fragment, forming acetyl CoA coenzyme A is removed and the remaining 2-carbon skeleton is attached to an existing 4-carbon (oxaloacetate) molecule that serves as the starting point for the citric acid cycle The new 6-carbon (citrate) chain is partially broken down, releasing carbon dioxide (CO2) Several electrons are captured by electron carriers... and more carbon dioxide (CO2) is released 2 ATPs are produced by the citric acid cycle for each molecule of glucose At this point, only a small # of ATPs have been produced However, more energy is available in the electrons that are being transported by electron carriers While the citric acid cycle starts another round, lets follow an electron carrier to the next step in the process (oxidative phosphorylation: electron transport and chemiosmosis) oxidative phosphorylation: electron transport and chemiosmosis: electron carriers such as NADH deliver their electrons to an electron transport chain embedded in the inner membrane of the mitochondrion The chain consists of a series of electron carriers, most of which are proteins that exist in large complexes Electrons are transferred from one electron carrier to the next in the electron transport chain Lets take a closer look at the path electrons take through the chain As eletrons move along each step of the chain, they give up a bit of energy The oxygen you breathe pulls the electrons from the transport chain.. and water is formed as a by-product The energy released by electrons is used to pump hydrogen ions across the inner membrane of the mitochondrion creating an area of high hydrogen ion concentration Hydrogen ions flow back across the membrane through a turbine Much like water through a dam, the flow of hydrogen ions spins the turbine, which activates the production of ATP These spinning turbines in your cells produce most of the ATP that is generated from the food you eat

The reactions of cellular respiration can be broken down into four stages:

1. glycolysis 2. acetyl coenzyme A (acetyl CoA) formation 3. citric acid cycle (also known as the Krebs cycle) 4. oxidative phosphorylation (electron transport and chemiosmotic ATP synthesis)

Yuki has drawn a flow chart to track the major inputs and outputs in cellular respiration. Select the most suitable set of labels for the numbered arrows.

1. produces 2. produces pyruvate used in 3. transfers electrons to

Maria has drawn a flow chart using stars to track electron carriers (NADH and FADH2) during cellular respiration, but she hasn't completed her model. If twelve electron carriers are delivered to the electron transport chain (ETC) per molecule of glucose, how many stars should she show being produced during glycolysis and pyruvate processing?

2 stars + 2 stars Glycolysis and pyruvate processing each produce two NADH molecules, so two stars should be drawn into the model for each process. There are two moleculea of NADH are synthesised in the glycolysis. And two molecules of NADH are processed during pyruvate processing. 6 molecules of NADH are produced in kreb cycle and 2 FADH2 are produced. Hence 2+2+6+2=12 total star are produced.

How many ATP total are produced by all the processes of cellular respiration combined?

31

What is the electron transport chain made up of?

4 protein complexes, a smaller cytochrome protein and an organic molecule called ubiquinone or Q for short

How many molecules of CO2 are needed as inputs to the Calvin cycle to produce one molecule of glucose?

6 molecules of CO2 are needed as inputs to the Calvin cycle to produce one molecule of glucose

Photosystem II (PSII) functions first (# reflects order of discovery) and is best at absorbing wavelength of ____

680nm

Carbon inputs to oxidative phosphorylation

All 6 of the carbon atoms that enter glycolysis in glucose are released as molecules of CO2 during the first three stages of cellular respiration. Think about whether any carbon compounds play a role in oxidative phosphorylation.

Citric Acid cycle (Krebs cycle)

Coenzyme A attaches to the 2-carbon fragment, forming acetyl CoA coenzyme A is removed and the remaining 2-carbon skeleton is attached to an existing 4-carbon (oxaloacetate) molecule that serves as the starting point for the citric acid cycle The new 6-carbon (citrate) chain is partially broken down, releasing carbon dioxide (CO2) Several electrons are captured by electron carriers... and more carbon dioxide (CO2) is released The carbon dioxide (CO2) that you exhale comes from the reactions of cellular respiration 2 ATPs are produced by the citric acid cycle for each molecule of glucose At this point, only a small # of ATPs have been produced However, more energy is available in the electrons that are being transported by electron carriers While the citric acid cycle starts another round, lets follow an electron carrier to the next step in the process (oxidative phosphorylation: electron transport and chemiosmosis)

Each of the four stages of cellular respiration occurs in a specific location inside or outside the mitochondria. These locations permit precise regulation and partitioning of cellular resources to optimize the utilization of cellular energy. Match each stage of cellular respiration with the cellular location in which it occurs. Labels may be used once, more than once, or not at all.

Glycolysis: cytosol Acetyl CoA formation: mitochondrial matrix Citric acid cycle: mitochondrial matrix Oxidative phosphorylation: inner mitochondrial membrane Cellular respiration begins with glycolysis in the cytosol. Pyruvate, the product of glycolysis, then enters the mitochondrial matrix, crossing both the outer and inner membranes. Both acetyl CoA formation and the citric acid cycle take place in the matrix. The NADH and FADH2 produced during the first three stages release their electrons to the electron transport chain of oxidative phosphorylation at the inner mitochondrial membrane. The inner membrane provides the barrier that creates an H+ gradient during electron transport, which is used for ATP synthesis.

Carbon fixation involves the addition of carbon dioxide to _____

In the Calvin cycle, carbon dioxide is added to RuBP.

What are the electron carriers in glycolysis?

In the overall process of glycolysis, one molecule of glucose is oxidized to produce two molecules of pyruvate. Recall that oxidation means the loss of electrons, and that the electrons removed from glucose must be passed on to some other molecule, called an electron carrier. The conversion of glucose to pyruvate in glycolysis involves the removal of electrons from glucose. These electrons are passed to the electron carrier NAD+, converting it to NADH.

Why is the citric acid cycle a cyclic pathway rather than a linear pathway?

In the oxidation of pyruvate to acetyl CoA, one carbon atom is released as CO2. However, the oxidation of the remaining two carbon atoms—in acetate—to CO2 requires a complex, eight-step pathway—the citric acid cycle. Consider four possible explanations for why the last two carbons in acetate are converted to CO2 in a complex cyclic pathway rather than through a simple, linear reaction. It is easier to remove electrons and produce CO2 from compounds with 3 or more carbon atoms than from a 2-carbon compound such as acetyl CoA.

What are the electron carriers in Acetyl CoA formation?

In the production of acetyl CoA, one molecule of pyruvate is first oxidized to acetate, then coenzyme A (CoA) is added to form acetyl CoA. Recall that oxidation is the loss of electrons, and that the electrons removed from pyruvate must be passed to an electron carrier. NAD+ and NADH The conversion of pyruvate to acetyl CoA involves the removal of electrons from pyruvate. Those electrons are passed to the electron carrier NAD+, converting it to NADH.

What are the net inputs and outputs of Acetyl CoA formation?

Inputs: coenzyme A pyruvate NAD+ Outputs: CO2 acetyl CoA NADH In acetyl CoA formation, pyruvate (a product of glycolysis) is oxidized to acetyl CoA, with the reduction of NAD+ to NADH and the release of one molecule of CO2

Acetyl CoA formation

Lets follow the pyruvic acid molecule produced in gylcolysis into a mitochondrion to see where most of the energy is extracted After glycolysis, as the pyruvic acid molecule enters the mitochondrion, one carbon is removed forming carbon dioxide as a by-product Electrons are stripped forming NADH Coenzyme A attaches to the 2-carbon fragment, forming acetyl CoA coenzyme A is removed and the remaining 2-carbon skeleton is attached to an existing 4-carbon molecule that serves as the starting point for the citric acid cycle

Draw a flow chart showing the relationship between the light-capturing reactions and the calvin cycle

O2 is a product of the light-capturing reactions ATP and NADPH are forms of chemical energy that are produced by the light-capturing reactions and used in the calvin cycle CO2 enters the calvin cycle and sugars or carbohydrates are produced by the calvin cycle energy flows in a linear way from sunlight-->light-capturing reactions-->ATP+NADPH-->calvin cycle-->sugars The location of the pigment chlorophyll is in the light-capturing reactions box The flow of electrons goes H20-->light-capturing reactions-->ATP+NADPH-->calvin cycle-->sugars The pathway of carbon atoms goes from CO2-->calvin cycle-->sugars remember the oxygen atoms that originate in water are just a waste product of photosynthesis

In glycolysis, glucose (a 6-carbon molecule) is broken down to form 2 molecules of pyruvate. Then, during acetyl CoA formation, pyruvate is converted to acetyl CoA through a series of reactions. Which statement is true about the number of carbon atoms in the compounds involved in acetyl CoA formation?

Pyruvate is a 3-carbon molecule, while acetyl CoA is a 2-carbon molecule. 1 molecule of CO2 is released.

electrochemical gradient

The diffusion gradient of an ion, which is affected by both the concentration difference of an ion across a membrane (a chemical force) and the ion's tendency to move relative to the membrane potential (an electrical force).

How is ATP produced from a molecule of glucose? (glycolysis)

The first step is called glycolysis, which takes place outside the mitochondria To begin the process, some energy has to be invested Next, the molecule of glucose is split in half Now, the molecule of NAD+, an electron carrier, picks up electrons and hydrogen atoms from the carbon molecule becoming NADH In the final steps of glycolysis, some ATP is produced, but not much—for every glucose molecule only 2 net ATPs are produced outside the mitochondrion However, glycolysis has produced pyruvic acid, which still has a lot of energy available.

Photostem II

Uses light energy to oxidize water molecules, producing electrons, protons (H+), and O2. Requires photons that are slightly more energetic than what are required for photostem I.

oxidative phosphorylation: electron transport and chemiosmosis

While the citric acid cycle starts another round, lets follow an electron carrier to the next step in the process (oxidative phosphorylation: electron transport and chemiosmosis) electron carriers such as NADH deliver their electrons to an electron transport chain embedded in the inner membrane of the mitochondrion The chain consists of a series of electron carriers, most of which are proteins that exist in large complexes Electrons are transferred from one electron carrier to the next in the electron transport chain Lets take a closer look at the path electrons take through the chain As eletrons move along each step of the chain, they give up a bit of energy The oxygen you breathe pulls the electrons from the transport chain.. and water is formed as a by-product The energy released by electrons is used to pump hydrogen ions across the inner membrane of the mitochondrion creating an area of high hydrogen ion concentration Hydrogen ions flow back across the membrane through a turbine Much like water through a dam, the flow of hydrogen ions spins the turbine, which activates the production of ATP These spinning turbines in your cells produce most of the ATP that is generated from the food you eat

What is a coenzyme?

a nonprotein compound that is necessary for the functioning of an enzyme.

stages of photosynthesis

light reactions and calvin cycle

Sort the following items according to whether they are reactants or products in the anaerobic reduction of pyruvate during lactic acid fermentation. lactate NADH NAD+ Pyruvate

reactants: NADH pyruvate products: lactate NAD+ When an animal engages in strenuous usage of its muscles, anaerobic conditions ensue, and pyruvate is reduced to lactate. In the process, NADH is oxidized to NAD+. This NAD+ can further oxidize glyceraldehyde-3-phosphate to produce more ATP.

Electron Transport Chain (ETC)

series of electron carrier proteins that shuttle high-energy electrons during ATP-generating reactions uses the high-energy electrons from the Krebs cycle to convert ADP into ATP A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.

What is the overall function of the electron transport chain?

to receive electrons from NADH and FADH2 and move them through a series of redox reactions When the electrons are in the NADH and FADH2 molecules, they have a relatively high energy level and they lose a little free energy w/ each redox exchange

What is the fate of carbon atoms entering the citric acid cycle?

with each turn of the citric acid cycle, 2 carbon atoms from the acetyl group of acetyl CoA join with the 4-carbon oxaloacetate (the last intermediate in the citric acid cycle) to form citrate, a 6-carbon acid. In the remaining steps of the citric acid cycle, the 6-carbon citrate is converted back to the 4-carbon oxaloacetate. What happens to the other two carbon atoms? They are released as 2 CO2 molecules. For each turn of the citric acid cycle, 2 carbon atoms enter in the acetyl group of acetyl CoA and leave as 2 CO2 molecules.

light reactions (stage one of photosynthesis)

zooming into a chloroplast, we see these flattened membranous sacs called thylakoids Here, light energy is converted to chemical energy in the first stage of photosynthesis, the light reactions photosystems—large complexes of proteins—and chlorophyll capture light energy An electron transport chain connects the two photosystems A small mobile electron carrier shuttles electrons from one large complex to another Now, lets take a closer look at the steps of light reactions The photosystem on the left absorbs light energy, exciting electrons that enter the electron transport chain Electrons are replaced with electrons stripped from water, creating oxygen as a by-product The energized electrons flow down the electron transport chain, releasing energy that is used to pump hydrogen ions into the thylakoid In the photosystem on the right, light energy excites electrons, and this time the electrons are captured by an electron carrier molecule—NADPH The high concentration of hydrogen ions inside the thylakoid powers ATP synthase, producing ATPs The light reactions in the thylakoid have produced 2 energy products—ATP and NADPH—that will now power the production of sugar in the calvin cycle

What are the electron carriers in glycolysis?

NAD+ and FAD

Where does the citric acid cycle occur?

matrix of mitochondria

In glycolysis, ATP molecules are produced by _____.

substrate-level phosphorylation A phosphate group is transferred from glyceraldehyde phosphate to ADP.

What is the product of photosynthesis?

sugar

_________ provides the energy to do the work of building energy-rich sugar molecules.

sunlight

Osmosis

Diffusion of water through a selectively permeable membrane

The light-capturing reactions convert 1.____ and the Calvin cycle converts the 2.____

1. light energy to chemical energy in ATP and NADPH, 2. chemical energy in these molecules to chemical energy in sugars.

energy investment phase of glycolysis

2 ATP are invested to make the glucose molecule less stable some ATP energy is used to start the process of glucose oxidation By the end of this phase, a 6-carbon molecule (glucose) has been split into 3-carbon molecules of glyceraldehyde-3-phosphate The 3-carbon glyceraldehyde-3-phosphate molecules now enter the energy-payoff phase

For every molecule of O2 that is released by photosystem II, ___ H20 molecules are needed, which together pass ___ electrons to the PSII reaction-center complex

2, 4 Each water molecule donates one oxygen and two electrons. So two water molecules are needed for every molecule of O2 released by PS II, and four electrons are donated to the PS II reaction-center complex. Four protons (H+) are released during the process.

In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?

3

How many molecules of ATP are produced in cellular respiration?

30-32

How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?

6

How much of H20 is produced in the electron transport chain?

6 molecules of H20

Photosystem I (PSI) best at absorbing wavelength of _____

700nm(P700)

oxaloacetate

A 4-carbon molecule that binds with the 2-carbon acetyl unit of acetyl-CoA to form citric acid in the first step of the citric acid cycle

citrate

A 6-carbon molecule; it is synthesized from oxaloacetate and acetyl CoA in the first step of the citric acid cycle.

chemiosmosis

A process for making ATP using the energy of an electrochemical gradient and the ATP synthase enzyme.

What are the electron carriers in the citric acid cycle?

As in glycolysis, the electrons removed from carbon-containing intermediates during acetyl CoA formation and the citric acid cycle are passed to the electron carrier NAD+, reducing it to NADH. The citric acid cycle also uses a second electron carrier, FAD (flavin adenine dinucleotide), the oxidized form, and FADH2, the reduced form.

how many pyruvic acids are produced in glycolysis?

Glycolysis starts with 1 molecule of glucose and ends with 2 pyruvate (pyruvic acid) molecules, a total of 4 ATP molecules, and 2 molecules of NADH

Where do the electrons come from in photosynthesis

H20

In the light reactions, light energy is used to oxidize _____ to ____

H20 to O2

What is the matrix of the mitochondrion?

Innermost compartment of the mitochondrion

What are the inputs and outputs of the calvin cycle (photosynthesis)

Input: ATP NADPH CO2 Output: ADP NADP+ G3P

What are the inputs and outputs of the light reactions

Input: Light water NADP+ ADP Output: O2 ATP NADPH

What are the net inputs and outputs of Oxidative Phosphorylation?

Inputs: NADH O2 ADP Outputs: NAD+ ATP Water In oxidative phosphorylation, the NADH and FADH2 produced by the first three stages of cellular respiration are oxidized in the electron transport chain, reducing O2 to water and recycling NAD+ and FAD back to the first three stages of cellular respiration. The electron transport reactions supply the energy to drive most of a cell's ATP production.

What are the net inputs and outputs of the citric acid cycle?

Inputs: acetyl CoA NAD+ ADP Outputs: NADH ATP coenzyme A CO2 In the citric acid cycle, the two carbons from the acetyl group of acetyl CoA are oxidized to two molecules of CO2, while several molecules of NAD+ are reduced to NADH and one molecule of FAD is reduced to FADH2. In addition, one molecule of ATP is produced.

What are the net inputs and outputs of glycolysis?

Inputs: glucose NAD+ ADP Outputs: Pyruvate NADH ATP

ATP synthase

Large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

First redox reaction of the electron transport chain

NADH donates its electrons to protein complex 1 This redox reaction reduces the flavoprotein and oxidizes NADH to NAD+

oxidative phosphorylation reactants

NADH, FADH2, O2, ADP, phosphate (P)

The electrons derived from this oxidation reaction in the light reactions are used to reduce _____ to _____

NADP+ to NADPH

After 3-PGA is phosphorylated, it is reduced by _____

NADPH

The Calvin cycle oxidizes the light-reactions product _____ to _____

NADPH to NADP+

Which of the following statements about the citric acid cycle is most accurate? The citric acid cycle occurs as part of both cellular respiration and photosynthesis. Oxygen and water are produced in the citric acid cycle. The citric acid cycle is the first step in cellular respiration. Not all living things engage in the citric acid cycle.

Not all living things engage in the citric acid cycle. The citric acid cycle is a process that only occurs is eukaryotes.

What is the final electron acceptor?

O2

_______is the final electron acceptor of the electron transport chain.

O2 (molecular oxygen)

chemiosmosis

Process by which a Hydrogen pump pumps protons into the thylakoid membrane. H+ passively flows through the ATP synthase which leads to the creation of ATP.

Fermentation

Process by which cells release energy in the absence of oxygen An anaerobic pathway for breaking down glucose

anaerobic

Process that does not require oxygen

aerobic

Process that requires oxygen

energy generation phase of glycolysis

Produces 4 ATP, 2 NADH, and 2 pyruvate or 2 lactate

Identify each of the following molecules as reactants or products of the citric acid cycle: Acetyl CoA Carbon dioxide NAD+ NADH FADH2 FAD ADP ATP

Reactants: Acetyl CoA NAD+ FAD ADP Products: Carbon dioxide (CO2) ATP NADH FADH2

Cytoplasm

The contents of a cell between the plasma membrane and the nuclear envelope; includes cytosol which is the jelly-like substance that fills the space between organelles

Mitochondria

The eukaryotic cell structure where cellular respiration occurs

the calvin cycle (stage two of photosynthesis)

The light reactions in the thylakoid have produced 2 energy products—ATP and NADPH—that will now power the production of sugar in the calvin cycle The calvin cycle takes place outside the thylakoids in the stroma—the thick fluid of the chloroplast As the beginning of the calvin cycle, carbon dioxide molecules combine with molecules called RuBP The resulting molecules go through a series of reactions powered by ATP and NADPH from the light reactions Sugar molecules known as G3Ps are produced Most of the G3Ps are rearranged back into RuBP that will begin the calvin cycle again But the important product of photosynthesis is the remaining G2P sugar Some G3Ps are used to build glucose, which can combine into starch or cellulose Still other G3Ps form sucrose And some of the sugar is broken down by cellular respiration using oxygen in the plant's own mitochondria, generating ATPs that can power the other work of the plant Excess oxygen diffuses out of the leaf through the pores, while more carbon dioxide enters With 3 simple ingredients—carbon dioxide, water, and light—plants produce sugar and oxygen by photosynthesis, powering plant metabolism and ultimately providing your fuel as well

Cellular respiration

The process by which organisms break down glucose into a form that the cell can use as energy

peripheral protein

a protein appendage loosely bound to the surface of a membrane and not embedded in the lipid bilayer loosely bound to the surface of a cellular membrane

enzyme-catalyzed reaction

a substrate attaches to the active site. an enzyme-substrate (ES) complex forms. reaction occurs and products are released. an enzyme is used over and over.

integral protein

a type of membrane protein that is permanently attached to the biological membrane. they are embedded within a cellular membrane

What are the reactants in the citric acid cycle?

acetyl CoA, NAD+, FAD, ADP

Whats an oxidizing agent?

an electron acceptor

What are the two phases of glycolysis?

energy investment phase and energy generation phase

Rubisco

enzyme that converts inorganic carbon dioxide molecules into organic molecules during the final step of the Calvin cycle

Recall that wineries use fermentation to turn grape sugar into alcohol. This may help you remember that alcohols are a typical product of fermentation.

ethanol: fermentation in yeast and bacteria

Match each product of pyruvate metabolism with the condition under which it is produced.

lactate: fermentation in human muscle cell ethanol: fermentation in yeast and bacteria acetyl CoA: aerobic oxidation In the presence of oxygen, human cells carry out aerobic respiration, which yields acetyl CoA. In the absence of oxygen, human cells can carry out lactic acid fermentation, which yields lactate. Yeasts and many bacteria carry out alcohol fermentation, which takes place under anaerobic conditions, and produces ethanol.

What does ATP do?

powers the work of the cell, such as muscle contraction

Net redox reaction in acetyl CoA formation and the citric acid cycle

pyruvate is oxidized to CO2 NAD+ is reduced to NADH and FAD is reduced to FADH2 As in glycolysis, the electrons removed from carbon-containing intermediates during acetyl CoA formation and the citric acid cycle are passed to the electron carrier NAD+, reducing it to NADH. The citric acid cycle also uses a 2nd electron carrier, FAD (flavin adenine dinucleotide), the oxidized form, and FADH2, the reduced form.

substrate

reactant of an enzyme-catalyzed reaction

When something gains electrons its in its _____ state

reduced

What is found inside the stroma (chloroplast)?

rubisco

What is cytoplasm?

the portion of the cell outside the nucleus

linear electron flow

the primary pathway, involves both photosystems and produces ATP and NADPH using light energy H2O → P680 chlorophyll a pair → PS II primary electron acceptor → Pq → cytochrome complex → Pc → P700 chlorophyll a pair → PS I primary electron acceptor → Fd → NADPH Electrons flow through the components of the linear electron pathway from water to NADPH.

What produces most of the ATP?

the spinning turbines in electron transport chain during oxidative phosphorylation

What is the net gain of ATP in cellular respiration?

there is an investment of 2 ATP during the start of glycolysis. So the net gain of ATP = 31 - 2= 29 (bc 31 ATP total) IN = 2 ATP, and OUT = 4 + 2 + 25 = 31 ATP. So ATP OUT minus ATP IN = 31 - 2 = 29 ATP.

Where in the chloroplast is are ATP and NADPH produced?

thylakoid membrane

Where in the chloroplast is chlorophyll found?

thylakoid membrane

The nuclear pore complex regulates molecular traffic in and out of the nucleus. Which molecules and cellular components pass through the nuclear pore during normal cellular activity?

mRNA and ribosomal subunits Ribosomal subunits (made from rRNA and protein) and mRNA are synthesized within the nucleus for use in the cytoplasm. The gateway between the nucleus and the cytoplasm is the nuclear pore.

redox reaction

A chemical reaction involving the transfer of one or more electrons from one reactant to another; also called oxidation-reduction reaction.

In glycolysis there is a net gain of _____ ATP.

2 ATP It takes 2 ATP to produce 4 ATP.

What does glycolysis produce?

2 ATP, 2 NADH, 2 pyruvate Thus, it ends with 4 ATP (net gain of 2) 2 NADH, and 2 pyruvic acid molecules

How many NADH are produced by glycolysis?

2 NADH

_____is a nonprotein organic electron carrier within the electron transport chain.

Q (ubiquinone)

Where does chemiosmosis occur?

inner membrane of mitochondria

Where does oxidative phosphorylation occur?

inner membrane of mitochondria

Where does the electron transport chain occur?

inner membrane of mitochondria

Where is the electron transport chain located?

inner membrane of mitochondria

What type of protein is ATP synthase?

integral protein

What type of protein is photosystem II?

integral protein

What is found inside the matrix (mitochondrion)?

isocitrate dehydrogenase

As the [H+] increases what happens to the pH?

it decreases

When animal muscles metabolize glucose faster than they can be supplied with oxygen, fermentation takes place, producing lactate rather than acetyl CoA. Organisms that normally produce energy using oxygen as an electron acceptor can use fermentation instead to generate energy when oxygen is absent.

lactate: fermentation in human muscle cell

In C3 plants the conservation of water promotes _____.

photorespiration Conserving water simultaneously reduces the amount of carbon dioxide available to the plant.

How many electrons at a time are passed between the pigment molecules in the light-harvesting complexes?

0 The excited state energy of the electron passes between pigment molecules, not the electron itself.

prokaryotic cell

A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles; found only in the domains Bacteria and Archaea.

In cellular respiration, energy in fuel is converted to

ATP

In glycolysis, what starts the process of glucose oxidation?

ATP Some ATP energy is used to start the process of glucose oxidation.

oxidative phosphorylation products

ATP, NAD+, FAD, H2O

ATP

Adenosine triphosphate, the primary energy carrier in living things

Substarte Level Phosphorylation

An enzyme transfers a phosphate group directly directly from a molecule to ADP (ATP can be used right away)

The electrons derived from this oxidation reaction in the Calvin cycle are used to reduce _____ to _____

CO2 to G3P

______is a multi-protein complex within the electron transport chain.

Complex III

Eukaryotic cells

Contain a nucleus and other organelles that are bound by membranes.

Which of these is NOT a product of glycolysis? NADH ATP FADH2 pyruvate

FADH2 FADH2 is a product of the citric acid cycle.

_____is a prosthetic group present in several components of the electron transport chain.

Fe-S

In the citric acid cycle another pair of electron carriers shuttles electrons in addition to NAD+/NADH. What is the second pair of electron carriers in the citric acid cycle?

NAD+ is reduced to NADH and FAD (the oxidized form) and FADH2 (the reduced form)

____ donates electrons to the electron transport chain.

NADH

Is the citric acid cycle a part of the process of photosynthesis?

No, the citric acid cycle is only a part of cellular respiration

What are the products of oxidative phosphorylation?

Oxidative phosphorylation produces 24-28 ATP molecules ATP, NAD+, and FAD+

oxidative phosphorylation

Part of the electron transport chain. A process occurring in the mitochondria that results in the formation of ATP from the flow of electrons across the inner membrane to bind with oxygen.

Photosynthesis flow chart

Sunlight drives light-capturing reactions H20 donates electrons to light-capturing reactions which release O2 The light-capturing reactions produce ATP and NADPH The yellow highlight represents the flow of energy

It would be appropriate for Jamal to label sugars and ATP as forms of chemical energy

TRUE

Most ATP is made where?

The cell's mitochondria

What are the products of the citric acid cycle?

The citric acid cycle is a series of reactions that produces 2 carbon dioxide molecules, 1 GTP/ATP, and reduced forms of NADH and FADH2. carbon dioxide (CO2), NADH, FADH2, and ATP

When a pigment molecule in a light-harvesting complex absorbs a photon of light, what happens to its excited-state electron?

The electron falls back to its ground state, while passing its excited-state energy to an electron in a nearby pigment molecule. The electron itself does not move through the antenna complex pigments, just the energy that excites the next electron.

Phosphofructokinase

The enzyme that catalyzes the phosphorylation of fructose-6-phosphate to form fructose-1-6-bisphosphate in the third step of glycolysis. This is the main regulatory step of glycolysis. PFK is feedback-inhibited by ATP.

Is there a net input or output of ATP in glycolysis?

There is a net output of ATP. In glycolysis, ATP is both consumed in the early steps and produced in the later steps. Because more ATP is produced per glucose molecule than is required, there is a net output of 2 ATP per glucose molecule.

Why are electron carriers important?

They transport electrons to reactions in the mitochondria

At the end of the electron transport chain, the oxygen molecule, O2, is the _____ of all the passed electrons

final electron acceptor

photosytem I

creates NADPH in light reaction

cyclic vs noncyclic photophosphorylation

cyclic reaction creates more ATP In cyclic photophosphorylation, electrons are returned to chlorophyll. In noncyclic photophosphorylation, chlorophyll receives electrons from hydrogen atoms.

In C4 and CAM plants carbon dioxide is fixed in the _____ of mesophyll cells.

cytoplasm

Where are ribosomes located?

cytoplasm and rough ER

NADPH

electron carrier that provides high-energy electrons for photosynthesis reduced form of NADP+

What happens during oxidative phosphorylation?

electron transport and chemiosmotic ATP synthesis All of the reduced electron carriers are oxidized by oxygen through the electron transport chain

free energy

energy that is available to do work

What type of protein is rubisco?

free protein

What is the overall reaction of glycolysis?

glucose+2NAD+2Pi+2ADP to 2pyruvate+2NADH+2H+2ATP+2H2O

What part of cellular respiration occur in the cytoplasm (cytosol)?

glycolysis

Alfred has drawn a flow chart to show a time sequence of four processes of cellular respiration. Which sequence of three labels is the best choice to finish his model?

glycolysis / pyruvate processing / citric acid cycle

For each glucose molecule broken down during glycolysis, a net of ___ ATPs are formed, along with ___ NADH molecules

net of 2 ATPs are formed, along with 2 NADH molecules

free protein

not associated with a membrane at all

Where does glycolysis occur?

outside the mitochondria in the cytoplasm

When something loses electrons its in its _____ state

oxidized

Is the formation of acetyl CoA oxidation or reduction? When pyruvate is _____ to acetyl CoA, NAD+ is reduced to NADH.

oxidized In the paired oxidation-reduction (redox) reactions, NAD+ is reduced to NADH as pyruvate is oxidized to acetyl CoA. acetyl CoA: aerobic oxidation

______ is a waste product of photosynthesis

oxygen

What is glycolysis?

the breakdown of glucose by enzymes, releasing energy and pyruvic acid. Glycolysis literally means "splitting sugars." Glycolysis yields two molecules of ATP. It can be divided into two main phases

What is the stroma of a chloroplast?

the fluid inside the chloroplast but outside the thylakoids

In what part of the cell does the citric acid cycle take place?

the inner space of the mitochondria

C4 plants differ from C3 and CAM plants in that C4 plants _____.

transfer fixed carbon dioxide to cells in which the Calvin cycle occurs In C3 and CAM plants carbon dioxide fixation and the Calvin cycle occur in the same cells.

In reactions such as acetyl CoA formation, there must be the same number of carbon atoms as inputs as there are as outputs

true

Once an oxygen atom in O2 has gained 2 electrons, it picks up 2 protons from the solution in the mitochondrion and becomes _____

water

____ is used in the light reactions, and ______ ______ is used in the calvin cycle

water, carbon dioxide

What does the citric acid cycle produce?

1 ATP (GTP), 3 NADH, 1 FADH2 In a single turn of the cycle, 2 carbons enter from acetyl CoA, and 2 molecules of carbon dioxide are released; 3 molecules of NADH and 1 molecule of FADH2 are generated; and 1 molecule of ATP or GTP is produced. These figures are for 1 turn of the cycle, corresponding to 1 molecule of acetyl CoA Each glucose produces 2 acetyl CoA, so we need to multiply these numbers by 2 if we want the per-glucose yield. 2 carbons—from acetyl CoA—enter the citric acid cycle in each turn, and 2 carbon dioxide molecules are released. However, the carbon dioxide molecules don't actually contain carbon atoms from the acetyl CoA that just entered the cycle. Instead, the carbons from acetyl CoA are initially incorporated into the intermediates of the cycle and are released as carbon dioxide only during later turns. After enough turns, all the carbon atoms from the acetyl group of acetyl CoA will be released as carbon dioxide.

Cytoplasm (cytosol)

A jellylike fluid inside the cell in which the organelles are suspended

Acetyl CoA

Acetyl coenzyme A; the entry compound for the citric acid cycle in cellular respiration, formed from a fragment of pyruvate attached to a coenzyme.

Which of the following occur during the citric acid cycle?

Acetyl-CoA combines with oxaloacetate to form citrate: Following pyruvate oxidation, acetyl-CoA joins with the 4-carbon oxaloacetate, forming the 6-carbon molecule called citrate. NAD+ is reduced to form NADH: Several intermediates in the citric acid cycle are oxidized, causing NAD+ to be reduced to NADH in the process.

In which organisms do cellular respiration and photosynthesis occur?

Cellular respiration occurs in both producers and consumers. Only producers can photosynthesize, but all organisms must perform cellular respiration, which fuels cellular work through the breakdown of glucose.

In the final steps of glycolysis, some ATP is produced. How many net ATPs are produced for every glucose molecule?

For every glucose molecule, only 2 net ATPs are produced outside the mitochondrion

Tracking the fate of carbon in cellular respiration

For example, you could draw a cartoon of glucose showing the 6 carbon as red balls, ignoring for now the oxygens and hydrogens, Then show that after glycolysis the 6 carbons end up in 2 molecules of pyruvate each w/ 3 carbons Then pyruvate is processed to form 2 molecules of carbon dioxide and 2 molecules of acetyl CoA, which enters the citric acid cycle and produces 4 more molecules of carbon dioxide This flow chart tracks the complete oxidation of glucose from a single molecule that has 6 carbons to 6 molecules each containing 1 carbon

Ribosome

Makes proteins

_____ and ____ store energy from the light reactions for use in the calvin cycle

NADPH and ATP

Plants require specific inputs to carry out photosynthesis and cellular respiration. Which of the following statements accurately reflect(s) what plants must take in? Plants take in carbon dioxide from the air Carbon dioxide enters plants from the soil Plants take in both carbon dioxide and oxygen Plants take in oxygen as an input for photosynthesis.

Plants take in carbon dioxide from the air. Plants take in both carbon dioxide and oxygen. Plants need carbon dioxide to perform photosynthesis and oxygen to perform cellular respiration. Both carbon dioxide and oxygen enter and leave the plant through the leaves.

Motor proteins are responsible for moving vesicles and organelles within the cell. Motor proteins move along protein "tracks." In the example shown in the Visualizing figure, what are those tracks made of?

actin As they move vesicles and organelles within the cell, the motor proteins shown in the Visualizing figure are "walking" along microfilaments made of actin.

What type of protein is NADP+ reductase?

peripheral protein

What type of protein is Pc?

peripheral protein

What is found inside the cytoplasm?

phosphofructokinase ribosome

What is found inside the Internal membrane of mitochondrion and/or chloroplast?

photosystem I ATP synthase

Chloroplast

the siste of photosynthesis in plant cells

Ribosome

the site of protein synthesis