Photosynthesis and Cellular Respiration Almost all plants are photosynthetic autotrophs, as are some bacteria and protists –Autotrophs generate their

Photosynthesis and Photosynthesis and Cellular RespirationCellular Respiration

• Almost all plants are photosynthetic autotrophs, as are some bacteria and protists– Autotrophs generate their own organic matter through

photosynthesis– Sunlight energy is transformed to energy stored in the

form of chemical bonds

(a) Mosses, ferns, andflowering plants

(b) Kelp

(c) Euglena (d) Cyanobacteria

THE BASICS OF PHOTOSYNTHESIS

ADP, ATP and ADP, ATP and Cellular Cellular

RespirationRespiration

Copyright Cmassengale

ATP

Making energy!

The pointis to make

ATP!

What Is ATP?What Is ATP?

Energy used by all CellsEnergy used by all Cells

Adenosine TriphosphateAdenosine Triphosphate

Organic molecule containing Organic molecule containing high-energy Phosphate bondshigh-energy Phosphate bonds


Cells spend a lot of time making ATP!

What’s thepoint?

Thepoint is to make

ATP!

What Does ATP Do for You?What Does ATP Do for You?

It supplies YOU withIt supplies YOU with ENERGY!ENERGY!


The energy needs of life

Organisms are endergonic systems What do we need energy for?

synthesis building biomolecules

reproduction movement active transport temperature regulation

ATP for energyATP powers cellular work- made in photosynthesis

amd cellular respiration A cell does three main kinds of work:

Mechanical work, beating of cilia, contraction of muscle cells, and movement of chromosomes(produces heat)

Transport work, pumping substances across membranes against the direction of spontaneous movement

Chemical work, driving endergonic reactions such as the synthesis of polymers from monomers

Chemical Structure of ATPChemical Structure of ATP

3 Phosphates

Ribose Sugar

Adenine Base


How Do We Get Energy From How Do We Get Energy From ATP?ATP?

By breaking By breaking the high- the high- energy energy bonds bonds between the between the last two last two phosphates phosphates in ATPin ATP


What is the Process Called?What is the Process Called?HYDROLYSIS (Adding HHYDROLYSIS (Adding H22O)O)

H2O


How Does That Happen?How Does That Happen?

An An Enzyme!Enzyme!


ATP

high energy bondsHow efficient!Build once,

use many ways

Adenosine Triphosphate modified nucleotide

AMP + Pi ADP

ADP + Pi ATP

How does ATP transfer energy?

PO–

O–

O

–O PO–

O–

O

–O PO–

O–

O

–O7.3

energy+PO–

O–

O

–O

ATP ADP

BONDS ALWAYS CONTAIN ENERGY!!!

WHEN YOU BREAK A BOND ENERGY IS RELEASED!!

FORMING A BOND TAKES ENERGY!!

ADPATP

How Does ATP Work? So what? Energy is stored in these bonds. So? The breaking of the chemical bond releases the

energy

ATP + H2O→ ADP + P + ENERGY ATP is made in photosynthesis and respiration!!!

ATP (adenosine triphosphate) is a a molecule that carries energy that cells can use.

How Does ATP Work? The bonds between phosphate groups can be

broken by hydrolysis which produces energy!!!

ATP has 3 phosphate groups The bond to the third bond is easily broken. When the third bond is broken, energy is released. Becomes ADP – no energy!!

ATP

Living economy Fueling the body’s economy

eat high energy organic molecules food = carbohydrates, lipids, proteins, nucleic acids

break them down catabolism = digest

capture released energy in a form the cell can use Need an energy currency

a way to pass energy around need a short term energy

storage molecule

Whoa! Hot stuff!

How is ATP Re-Made?How is ATP Re-Made?

The reverse of the previous process The reverse of the previous process occurs.occurs.

Another Enzyme Another Enzyme is used!is used!

ENERGY IS ENERGY IS NEEDEDNEEDED

ATP ATP SynthetaseSynthetaseCopyright Cmassengale

The ADP-ATP CycleThe ADP-ATP Cycle

ATP-ATP-asease

ATP ATP SynthetaSynthetasese


ATP / ADP cycleCan’t store ATP too reactive transfers Pi too

easily only short term

energy storage carbohydrates &

fats are long term energy storage

ATP

ADP P+

7.3 kcal/mole

A working muscle recycles over 10 million ATPs per second

Whoa!Pass me

the glucose(and O2)!

respiration

When is ATP Made in the When is ATP Made in the Body?Body?

During a During a Process called Process called Cellular Cellular RespirationRespiration that takes that takes place in both place in both Plants & Plants & AnimalsAnimals


High Energy Electrons and Molecules

Once the sun’s energy has been trapped and excited an electron, what happens to it?Electron Carrier: a molecule that picks up the electron and uses this energy to break apart bonds.Examples of electron carriers: NADP and ATPNADP captures two electrons of H and becomes NADPH.ADP becomes ATP!!!

Flashback January 20Flashback January 20

1. Write the equation for photosynthesis.1. Write the equation for photosynthesis. 2. Why are plants leaves green?2. Why are plants leaves green?

PhotosynthesisPhotosynthesis uses the energy of the sunlight to convert water and carbon dioxide(reactants) into high-energy sugars and oxygen(products)

Photosynthesis occurs in the parts of the chlorplasts.There are three parts involved.

Light Energy Harvested by Plants & Other Photosynthetic Autotrophs

6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2

THE SUN: WHY IS IT THE SUN: WHY IS IT IMPORTANT?IMPORTANT?

Source of light energySource of light energySource of heat energySource of heat energyGravitational attractionGravitational attraction

Source of radiationSource of radiationDay and nightDay and night

Source of all energy(electricity)Source of all energy(electricity)

Source of food for all organisms!!!!Source of food for all organisms!!!!

SUN’S SPECTRUMSUN’S SPECTRUM

Pigment and Light

Energy from the Sun travels to the Earth as light. We see sunlight as “white light” which is really different wavelengths(ROYGBIV).Plant gather the Sun’s energy with light-absorbing molecules called PIGMENTS.Pigments: photosynthetic organisms capture energy using pigments.Chlorophyll: pigments plants use to absorb light energy.Plant have different pigments.

WHYWHY ARE ARE PLA PLANTS NTS GREGREEN?EN?

Plant Cells have Green Chloroplasts

The thylakoid membrane of the chloroplast is impregnated with photosynthetic pigments (i.e., chlorophylls, carotenoids).

Chloroplasts absorb light energy and convert it to chemical energy. They absorb the reds and blue. Reflects the green.

That is why they look green.

LightReflected

light

Absorbedlight

Transmittedlight

Chloroplast

THE COLOR OF LIGHT SEEN IS THE COLOR NOT ABSORBED

Different pigments absorb light differently

Different Pigments– Chlorophyll a – green pigments in plants and

bacteria– Chlorophyll b in green algae– Carotenoids – orange, red, yellow when

chloroplast die in plants. Chlorophyll breaks down first in the fall so we see these colors.

– Xanthophyll – yellow pigments in lemons, corn, diatoms(protists)

Figure 7.7

Why are Chloroplast Important?

The chloroplasts absorb the Sun’s energy and use this energy to excite electrons which powers photosynthesis. To break apart water and carbon Dioxide, you must have energy!!!!

Monday January 23Monday January 23

Why are chloroplasts important to plants?Why are chloroplasts important to plants?

If plants have pigments other than green in If plants have pigments other than green in their chloroplasts, why are plants green?their chloroplasts, why are plants green?

Flashback Jan. 24Flashback Jan. 24

Sketch a chloroplast and label the parts.Sketch a chloroplast and label the parts.

Thylakoids:Thylakoids: flat compartments in the chloroplast that flat compartments in the chloroplast that contain chlorophyll. LIGHT DEPEDENT REACTION contain chlorophyll. LIGHT DEPEDENT REACTION occurs here.occurs here.GranaGrana: are stacks of thylakoids.: are stacks of thylakoids.StromaStroma: fluid that is all around the grana inside : fluid that is all around the grana inside the chorplast. LIGHT INDEPENDENT REACTION the chorplast. LIGHT INDEPENDENT REACTION occurs here.occurs here.

Parts of the Chloroplasts

Occurs in the membrane of the thylakoids

• Photosynthesis is the process by which autotrophic organisms use light energy to make sugar and oxygen gas from carbon dioxide and water

AN OVERVIEW OF PHOTOSYNTHESIS

Carbondioxide

Water Glucose Oxygengas

PHOTOSYNTHESIS

• The Calvin cycle makes sugar from carbon dioxide– ATP generated by the light

reactions provides the energy for sugar synthesis

– The NADPH produced by the light reactions provides the electrons for the reduction of carbon dioxide to glucose

LightChloroplast

Lightreactions

Calvincycle

NADP

ADP+ P

• The light reactions convert solar energy to chemical energy– Produce ATP & NADPH


Photosystems: cluster of chlorophyll and proteins absorb the sun’s energy and generate the high energy electrons that are passed to the electron carrier molecules.

Their energy ends up in ATP and NADPH

Electron transport chains and Electron transport chains and photosystemsphotosystems

PhotosynthesisPhotosynthesis Step 1 – Light Dependent Reaction The light reactions convert solar energy to

chemical energy. Takes place in thylakoids. Photosystem II and electron transport 1. chlorophyll absorbs the sun’s energy. 2. Energy as electrons is moved along the

membrane(electron transport chain) 3. Water is split into H and O. O released as waste

through stoma. 4. H is pumped over and over again in the

membrane until they build up.

The O2 liberated by photosynthesis is made from the oxygen in water (H+ and e-)

Plants produce OPlants produce O22 gas by splitting H gas by splitting H22OO

Electron Transport Chain

When the electrons are excited from the light reaction, they are passed along the membrane through the protein pumps. They passed from Photosystem II to photosystem I.

Flashback Jan 25Flashback Jan 25

Get out your notes and the “Colors of Get out your notes and the “Colors of Autumn” and study.Autumn” and study.

You will have a QUIZ shortly!!You will have a QUIZ shortly!! Know which pigments cause which colors!Know which pigments cause which colors!

PhotosynthesisPhotosynthesisPhotosystem IPhotosystem I

1.1.1. Electrons from photosytem II are moved 1. Electrons from photosytem II are moved along the membrane to photosystem I.along the membrane to photosystem I.

2.2.2. Chlorophyll continues to absorb sunlight 2. Chlorophyll continues to absorb sunlight and free electrons.and free electrons.

3.3.3. Electrons are added to NADPH which is 3. Electrons are added to NADPH which is the energy carrier for the rest of the energy carrier for the rest of photosynthesis.photosynthesis.

4.4.4. The electrons are pumped through a 4. The electrons are pumped through a channel as part of an enzyme ATP channel as part of an enzyme ATP synthase to make ATP.synthase to make ATP.

Summary of Light-dependent Reaction

* Energy is captured from sunlight and transferred to electrons(electron transport chain).

Water molecule pulled apart to provide H ions.

The ions are used to make ATP and NADPH.

Need: sunlight and water Produce: energy carrying molecules

and oxygen(waste).

The production of ATP

Thylakoidcompartment(high H+)

Thylakoidmembrane

Stroma(low H+)

Light

Antennamolecul

es

Light

ELECTRON TRANSPORT

CHAIN

PHOTOSYSTEM

II

PHOTOSYSTE

M I

ATP

SYNTHASE

Summary—Light Dependent Reactions

a. Overall inputlight energy, H2O.

b. Overall output ATP, NADPH, O2.

Flashback January 26Flashback January 26

WHY is sunlight so important to a plant’s WHY is sunlight so important to a plant’s ability to make sugar?ability to make sugar?

There are organisms that can make their There are organisms that can make their own sugars miles deep inside of the ocean. own sugars miles deep inside of the ocean. How do you think these organisms do that How do you think these organisms do that without ANY sunlight? without ANY sunlight?

You may use your phone to look it up if you You may use your phone to look it up if you have it with you!have it with you!

• Step 2 – Light Independent Reaction – CALVIN CYCLE Occurs in the stroma.

• The Calvin cycle makes sugar from carbon dioxide

1.ATP generated by the light reactions provides the energy for sugar synthesis

2.The NADPH produced by the light reactions provides the electrons for the reduction of carbon dioxide to glucose. Carbon Dioxide is used to make a 6 carbon sugar called glucose.

– END GOAL – to break carbon dioxide down and combine into glucose!!! Need energy to do this!! That is why ATP and NADPH was made!!


Light Independent Reaction Overview1. 6 Carbon dioxide added:Carbon Dioxide enters the plant from the atmosphere. Each CO2 bonds with a 5-carbon sugar.2. 12 Three-carbon molecules formed: ATP and NADPHuse enzymes in the stroma to split the six carbon into 3 carbon sugars. 3. 2 Three-carbon sugars removed to make a glucose: The other 3 carbon molecules (10) stay in cycle. When 2 leave, they form glucose.4. Three-carbon molecules recycled: Energy from ATP Change 3carbon molecules back into 5 carbon to start thecycle over again. *Energy provided by Light dependent reaction.The plants uses the carbohydrates to meet its energy needs to make all of the macromolecules that it needs(proteins, lipids,

carbs).

Overview Calvin Cycle

In put: ATP, NADPH, and Carbon dioxideOutput: GLUCOSE!!

The end goal – Make glucose from the SUN!!

Harvesting Chemical EnergyHarvesting Chemical Energy

Energy enters food chains (via autotrophs) Energy enters food chains (via autotrophs) we can look at how organisms use that we can look at how organisms use that energy to fuel their bodies.energy to fuel their bodies.

Plants and animals both use products of Plants and animals both use products of photosynthesis (glucose) for metabolic fuelphotosynthesis (glucose) for metabolic fuel

HeterotrophsHeterotrophs: must take in energy from : must take in energy from outside sources, cannot make their own outside sources, cannot make their own e.g. animalse.g. animals

. Photosystem II breaks down . Photosystem II breaks down water and produces what as a water and produces what as a

waste product?waste product?

A. Carbon DioxideA. Carbon Dioxide B. OxygenB. Oxygen C. WaterC. Water D. SugarD. Sugar

Which of the following is an energy carrier produced in

Photosystem I?

a. ATP c. ADP b. NAD d. All of the above

Where in plant cells are the energy-absorbing molecules for photosynthesis located?

A. stromaA. stroma B. ThylakoidsB. Thylakoids C. ATP synthaseC. ATP synthase D. MitochondriaD. Mitochondria

What happens to sugars that are made during photosynthesis?

A. They move directly into an electron A. They move directly into an electron transport chain.transport chain.

B. They go back into the Calvin CycleB. They go back into the Calvin Cycle C. They can be used for cellular C. They can be used for cellular

respirationrespiration D. They make ATP by bonding togetherD. They make ATP by bonding together

How does the Calvin Cycle differ from the light-

dependent reactions?

A. It takes place in the stromaA. It takes place in the stroma B. It takes place in the chloroplastB. It takes place in the chloroplast C. It requires lightC. It requires light D. It takes place in the thylakoidD. It takes place in the thylakoid

If Carbon-dioxide is removed from a plant’s environment, what would you

expect to happen to the plant’s production of high energy sugars?

A. More sugars producedA. More sugars produced B. Fewer sugars producedB. Fewer sugars produced C. Same number of sugars without the C. Same number of sugars without the

Carbon DioxideCarbon Dioxide D. Caron dioxide does not affect the D. Caron dioxide does not affect the

production of sugarproduction of sugar

Which pigment gives apples their ripe, rich color?

A. TanninsA. Tannins B. XanthocyaninsB. Xanthocyanins C. CarotenoidsC. Carotenoids D. Chlorophyll bD. Chlorophyll b

RELEASES CHEMICAL ENERGY RELEASES CHEMICAL ENERGY FROM SUGARS AND OTHER FROM SUGARS AND OTHER CARBON-BASED MOLECULES TO CARBON-BASED MOLECULES TO MAKE ATP WHEN OXYGEN IS MAKE ATP WHEN OXYGEN IS PRESENT!!!!PRESENT!!!!NO OXYGEN – FERMENTATION!!!!NO OXYGEN – FERMENTATION!!!!

Cellular RespirationCellular Respiration

The Purpose of Cellular Respiration

It is to make and break bonds to generate ATP and electrons.You end up with ATP, H ions and electrons.The electrons are sent to the Electron Transport Chain where they help to make ATP through ATP synthase.****Hydrogen ions are bonded with oxygen to make water which is used in photosynthesis.

HOW DO WE MAKE ATP?HOW DO WE MAKE ATP?

Just like in photosynthesis. ATP is made Just like in photosynthesis. ATP is made by pumping H across ATP synthase to by pumping H across ATP synthase to attach a P onto ADP. This is the goal of attach a P onto ADP. This is the goal of cellular respiration.cellular respiration.

Relationship between Photosynthesis and Cellular Respiration

The products on one are used for the other to produce ATP from the Sun!Creates the Carbon- Oxygen Cycle!!!

Carbon Oxygen Cycle

NADP and NAD

Photosynthesis use the electron carrier - NADP(nicotinmide adenine dinucleotide phosophate)Cellular respiration uses - NAD( nicotinmide adenine dinucleotide)

Cellular Respiration OverviewCellular Respiration Overview

Transformation of chemical energy in food Transformation of chemical energy in food into chemical energy cells can use: ATPinto chemical energy cells can use: ATP

These reactions proceed the same way in These reactions proceed the same way in plants and animals. Process is called plants and animals. Process is called cellular respirationcellular respiration

Overall Reaction:Overall Reaction: CC66HH1212OO66 + 6O + 6O22 → → 6CO 6CO22 + 6H + 6H22OO

Cellular Respiration Cellular Respiration

Glycolysis – Occurs before Cell. Resp.Glycolysis – Occurs before Cell. Resp. Krebs Cycle (Citric Acid Cycle)Krebs Cycle (Citric Acid Cycle) Electron Transport Chain (ETC)Electron Transport Chain (ETC)

Glucose

Glycolysis Krebs cycle

Electrontransport

Fermentation (without oxygen)

Alcohol or lactic acid

Overall ReactionOverall ReactionCC66HH1212OO66 + 6O + 6O22 → 6CO→ 6CO22 + 6H + 6H22O + 38 ATPO + 38 ATP

Overall this is a three stage processOverall this is a three stage process1.1. Glycolysis: before cellular respirationGlycolysis: before cellular respiration

• Occurs in the cytoplasmOccurs in the cytoplasm• Glucose is broken downGlucose is broken down

2.2. Krebs CycleKrebs Cycle• Breaks down pyruvate into CO2Breaks down pyruvate into CO2• Occurs in mitochondrial matrixOccurs in mitochondrial matrix

3.3. EElectron lectron TTransport ransport CChainhain• ATP is synthesized - Occurs in mito membraneATP is synthesized - Occurs in mito membrane

FlowchartFlowchartSection 9-2

Glucose(C6H1206)

+Oxygen

(02)

GlycolysisKrebsCycle

ElectronTransport

Chain

Carbon Dioxide

(CO2)+

Water(H2O)

+ATP

Cellular Respiration

Cellular Respiration OverviewCellular Respiration Overview

Breakdown of glucose begins in the Breakdown of glucose begins in the cytoplasm: the liquid matrix inside the cellcytoplasm: the liquid matrix inside the cell

After glycolysis, life diverges into two After glycolysis, life diverges into two forms and two pathwaysforms and two pathways Anaerobic cellular respiration (aka Anaerobic cellular respiration (aka

fermentation) No oxygen fermentation) No oxygen Aerobic cellular respiration I Oxygen needed!!Aerobic cellular respiration I Oxygen needed!!

ANAEROBIC VS. AEROBICANAEROBIC VS. AEROBIC

AnaerobicAnaerobic – no oxygen present – no oxygen present fermentation or lactic acid can be formed. fermentation or lactic acid can be formed. No oxygen then no cellular respiration.No oxygen then no cellular respiration.AerobicAerobic –oxygen present. If oxygen is –oxygen present. If oxygen is present , then cellular respiration can present , then cellular respiration can occur.occur.

Aerobic vs. AnaerobicAerobic vs. Anaerobic

Anaerobic Anaerobic DOES DOES NOTNOT require require oxygen-oxygen-

fermentationfermentation SimpleSimple fast fast produces smaller produces smaller

amounts of energy amounts of energy (ATP)(ATP)

Aerobic requires Aerobic requires oxygen – cellular oxygen – cellular respirationrespiration Yields Yields largelarge

amounts of amounts of energyenergy

What is this What is this energy molecule?energy molecule?

ATP, ATP, ATPATP, ATP, ATP

GlycolysisGlycolysis Glyco = glucoseGlyco = glucose Lysis = break downLysis = break down LOCATION: Occurs in the cytoplasmLOCATION: Occurs in the cytoplasm This stage occurs in BOTH aerobic and This stage occurs in BOTH aerobic and

anaerobic respirationanaerobic respiration Glucose breaks down into 2 pyruvate (2 Glucose breaks down into 2 pyruvate (2

ATP are also made) ATP are also made) Glucose is a 6-carbon sugar Glucose is a 6-carbon sugar Pyruvate is a 3-carbon molecule (there are two Pyruvate is a 3-carbon molecule (there are two

of them)of them)

Steps of Glycolysis

1.Two ATP molecules are used to energize a glucose molecule. 2. Glucose is split into 2 3 carbon molecules. Enzymes rearrange the molecules.3. Electrons are transferred to NADP. The carbon molecules are converted to pyurate which enters cellular respiration.

GlycolysisGlycolysis

End Product: Breaks glucose into 2 –3 End Product: Breaks glucose into 2 –3 carbon molecules called PYRUVIC ACID.carbon molecules called PYRUVIC ACID.

2 atoms of ATP are needed to breakdown 2 atoms of ATP are needed to breakdown this molecule.this molecule.

High energy electrons are passed to NAD High energy electrons are passed to NAD to form NADH(sent to ETC)to form NADH(sent to ETC)

4 ATPS are synthesized and 2 are used 4 ATPS are synthesized and 2 are used for a net gain of 2 ATPs.for a net gain of 2 ATPs.

Locatiom: CytoplasmLocatiom: Cytoplasm NO ONO O22 required required Energy YieldEnergy Yield net gain of net gain of 2 ATP 2 ATP at the at the

expense of 2 ATPexpense of 2 ATP 6-C glucose 6-C glucose TWO 3-C pyruvates TWO 3-C pyruvates Free eFree e-- and H and H++ combine with combine with organic ion organic ion

carrierscarriers called NAD called NAD++ NADH + H NADH + H++

(nicotinamide dinucleotide)Used in ETC. (nicotinamide dinucleotide)Used in ETC. Hydrogen attached to water.Hydrogen attached to water.

Glycolysis

Glucose

To the electron transport chain

Figure 9–Figure 9–3 Glycolysis3 Glycolysis

Glycolysis:

Step 1

2 Pyruvic acid

Glycolysis Reactants and ProductsGlycolysis Reactants and Products

ReactantsReactants 1 glucose 1 glucose Enzymes are neededEnzymes are needed 2 ATP are needed to start2 ATP are needed to start

ProductsProducts 2 Pyruvates (go to next 2 Pyruvates (go to next

step)step) 4 ATP (2 are gained)4 ATP (2 are gained) 2 NADH (go to ETC)2 NADH (go to ETC)

Really 10 steps with 10 different enzymes involved.

Main Goals of Krebs CycleMain Goals of Krebs Cycle

Transfer high energy electrons(NADPH Transfer high energy electrons(NADPH and FADH) to molecules that can carry and FADH) to molecules that can carry them to the electron transport chain.them to the electron transport chain.

* Form some ATP molecules.* Form some ATP molecules.

Citric Acid Production

Figure 9–6 Figure 9–6 The The Krebs CycleKrebs Cycle

Section 9-2

Mitochondrion

Krebs Cycle- MATRIXKrebs Cycle- MATRIX

Pyruvic acid(3carbon) enters Pyruvic acid(3carbon) enters mitochondria. In the innermost layer of mitochondria. In the innermost layer of mitochondria or the MATRIX pyruvic acid mitochondria or the MATRIX pyruvic acid are broken down into carbon dioxide and are broken down into carbon dioxide and acteyl CoA molecules.acteyl CoA molecules.

Acetyl- CoA combines with 4 carbon Acetyl- CoA combines with 4 carbon compounds forming a 6 carbon molecule compounds forming a 6 carbon molecule citric acid. Energy is released by breaking citric acid. Energy is released by breaking and reforming these bonds.and reforming these bonds.

Kreb CycleKreb Cycle

1. Pyruvate broken down1. Pyruvate broken down 2. Coenzyme A bonds to 2 carbon molecule2. Coenzyme A bonds to 2 carbon molecule 3. Citric Acid formed: 2 carbon bonded to 4 3. Citric Acid formed: 2 carbon bonded to 4

carbon. Coenzyme goes back to step 2.carbon. Coenzyme goes back to step 2. 4. Citric Acid brokendown: into 5 carbon sugar 4. Citric Acid brokendown: into 5 carbon sugar

carbon dioxide and NADHcarbon dioxide and NADH 5. 5 carbon sugar broken down: Into 4 carbon 5. 5 carbon sugar broken down: Into 4 carbon

sugar, NADH, ATP and Carbon dioxide.sugar, NADH, ATP and Carbon dioxide. 6. 4 carbon rearranged by enzymes. Molecules 6. 4 carbon rearranged by enzymes. Molecules

of NADH, FADH(electron carrier).of NADH, FADH(electron carrier).

Second Step: Citric Acid Cycle (Krebs Second Step: Citric Acid Cycle (Krebs Cycle)Cycle)

WhereWhere Mitochondrial matrix Mitochondrial matrix Energy YieldEnergy Yield 2 ATP and more e 2 ATP and more e--

Acetyl-CoA (2-C) combines with 4-C to form Acetyl-CoA (2-C) combines with 4-C to form 6-C CITRIC ACID6-C CITRIC ACID

Citric Acid (6-C) changed to 5-C then to a 4-C Citric Acid (6-C) changed to 5-C then to a 4-C Gives off a COGives off a CO22 molecule molecule NAD+ and FAD pick up the released eNAD+ and FAD pick up the released e--

FAD becomes FADHFAD becomes FADH22 NADNAD++ becomes NADH + H becomes NADH + H++

Cycle ALWAYS reforming a 4-C molecule Cycle ALWAYS reforming a 4-C molecule

Krebs Cycle Reactants and ProductsKrebs Cycle Reactants and Products

ReactantsReactants 2 Acetyl CoA2 Acetyl CoA

Remember when you Remember when you form a bond energy is form a bond energy is released!! This is the key!!released!! This is the key!!

ProductsProducts 2 ATP2 ATP 6 NADH (go to ETC)6 NADH (go to ETC) 2 FADH2 FADH22 (go to ETC) (go to ETC)

4 CO4 CO22 (given off as waste) (given off as waste)

Review of Mitochondria Review of Mitochondria StructureStructure

SmoothSmooth outer outer MembraneMembrane

FoldedFolded inner inner membranemembrane

Folds called Folds called CristaeCristae

Space inside Space inside cristae called the cristae called the MatrixMatrix


Products of Kreb CycleProducts of Kreb Cycle

High energy carriers – NADH and FADH – High energy carriers – NADH and FADH – This is the main goal!!!This is the main goal!!!

Carbon DioxideCarbon Dioxide 2 ATP molecules2 ATP molecules 4 carbon molecules to start again4 carbon molecules to start again HYDROGEN IONS ARE SENT DOWN HYDROGEN IONS ARE SENT DOWN

THE ELECTRON TRANSPORT CHAIN to THE ELECTRON TRANSPORT CHAIN to make ATP.make ATP.

Diagram of the ProcessDiagram of the Process

Occurs in Cytoplasm

Occurs in Matrix

Occurs across Cristae


Krebs CycleKrebs Cycle

Electron TransportElectron Transport

ATP synthesisATP synthesis

Electron Transport ChainElectron Transport Chain

WhereWhere inner membrane of mitochondria inner membrane of mitochondria called cristea.called cristea.

Energy YieldEnergy Yield Total of 32 ATP Total of 32 ATP OO22 combines with TWO H combines with TWO H++ to form H to form H22OO

Exhale - COExhale - CO22, H, H22O comes from cellular O comes from cellular

respirationrespiration

Electron Transport - Step 3Electron Transport - Step 3

1. Proteins inside the membrane of the mito. 1. Proteins inside the membrane of the mito. Remove electrons from NADPh and FADH.Remove electrons from NADPh and FADH.

2.2. Electrons(hydrogen) are transported down Electrons(hydrogen) are transported down the chain of the membrane to be pumped the chain of the membrane to be pumped across.across.

3.3. ATP synthase(enzyme) puts a P on ADP to ATP synthase(enzyme) puts a P on ADP to make ATP(END GOAL!!).make ATP(END GOAL!!).

4.4. Oxygen enters the cycle to pick up electrons Oxygen enters the cycle to pick up electrons and hydrogen ions to make water that and hydrogen ions to make water that leaves the cycle.leaves the cycle.


Electron carriers loaded with electrons and Electron carriers loaded with electrons and protons from the Kreb’s cycle move to this protons from the Kreb’s cycle move to this chain-like a series of steps (staircase).chain-like a series of steps (staircase).

As electrons drop down stairs, energy As electrons drop down stairs, energy released to released to form a total of 32 ATP – form a total of 32 ATP – Final Goal!!Final Goal!!

Oxygen waits at bottom of staircase, picks Oxygen waits at bottom of staircase, picks up electrons and protons and in doing so up electrons and protons and in doing so becomes water becomes water


Occurs in the cristae of the mitochondriaOccurs in the cristae of the mitochondria







Diagram of the ProcessDiagram of the Process

Occurs in Cytoplasm

Occurs in Matrix

Occurs across Cristae








Electron Transport Electron Transport ChainChainSection 9-2

Electron TransportHydrogen Ion Movement

ATP Production

ATP synthase

Channel

Inner Membrane

Matrix

Intermembrane Space

Mitochondrion

PhotosynthesisWhat happens to the glucose formed in photosynthesis?

PHOTOSYNTHESIS

GLUCOSE STARCH

CELLULOSE

LIPIDS

PROTEINS

CARBON DIOXIDE AND

WATER

Required to make plant cell walls. It is made of 100s of glucose molecules bonded together.

Glucose is chemically converted to fatty acids and glycerol to make lipids, which are needed to make plant cell membranes and seed storage oils.

Is used by roots and leaves to store excess glucose in an osmotically inactive form. It is made of 100s of glucose molecules.

Using nitrate ions absorbed by plant roots, glucose is converted first to amino acids then to protein.

The carbon dioxide can be used again in photosynthesis or may diffuse out of the leaf via the stomata

respiration

ATP

Eukaryote vs Prokaryote Glycolytic pathways

Anaerobic Cellular Anaerobic Cellular RespirationRespiration

Some organisms thrive in environments with little or no Some organisms thrive in environments with little or no oxygenoxygen Marshes, bogs, gut of animals, sewage treatment pondsMarshes, bogs, gut of animals, sewage treatment ponds

No oxygen used= ‘an’aerobicNo oxygen used= ‘an’aerobic Results in no more ATPResults in no more ATP, final steps in these pathways , final steps in these pathways

serve ONLY to regenerate NAD+ so it can return to pick serve ONLY to regenerate NAD+ so it can return to pick up more electrons and hydrogens in glycolysis.up more electrons and hydrogens in glycolysis.

End products such as ethanol and COEnd products such as ethanol and CO22 (single cell fungi (single cell fungi

(yeast) in beer/bread) or lactic acid (muscle cells)(yeast) in beer/bread) or lactic acid (muscle cells)

Two Types of FermentationTwo Types of Fermentation

Alcoholic Fermentation Alcoholic Fermentation Pyruvate converted to Pyruvate converted to

ethyl alcohol and COethyl alcohol and CO22

Carried out by yeast and Carried out by yeast and some bacteriasome bacteria

Used in producing alcohol Used in producing alcohol (both consumable and for (both consumable and for ethanol), and for bakingethanol), and for baking

Lactic Acid FermentationLactic Acid Fermentation Pyruvate converted to Pyruvate converted to

lactic acidlactic acid Carried out by muscles Carried out by muscles

when working hard when working hard (muscles need ATP but (muscles need ATP but can’t get Ocan’t get O22 ) )

Causes muscle soreness Causes muscle soreness and crampsand cramps

Alcohol FermentationAlcohol Fermentation

Pyruvate

C6H12O6 → 2 C2H5OH + 2CO2 + 2 ATP Word Equation

Sugar (glucose) → Alcohol (ethanol) + Carbon Dioxide + Energy (ATP)

Alcoholic FermentationAlcoholic Fermentation

CC66HH1212OO6 6 2 C2 C22HH55OH + 2 COOH + 2 CO22

(Ethyl Alcohol or Ethanol)

As a result of Alcoholic Fermentation,

Glucose is converted into 2 molecules of Ethyl Alcohol and 2

Molecules of Carbon Dioxide.

Importance of FermentationImportance of Fermentation Alcohol Industry - almost every society Alcohol Industry - almost every society

has a fermented beverage.has a fermented beverage. Baking Industry - many breads use yeast Baking Industry - many breads use yeast

to provide bubbles to raise the dough.to provide bubbles to raise the dough.

Alcoholic FermentationAlcoholic Fermentation

Bacteria and fungi (yeast)Bacteria and fungi (yeast)

Ethyl alcohol and carbon dioxide Ethyl alcohol and carbon dioxide are the end productsare the end products

Process used to form beer, wine, Process used to form beer, wine, and other alcoholic beveragesand other alcoholic beverages

Also used to raise dough, breadAlso used to raise dough, bread

Lactic Acid FermentationLactic Acid Fermentation

Uses only Glycolysis.Uses only Glycolysis. Does Does NOTNOT require O require O22

Produces ATP when OProduces ATP when O22 is not is not available.available.


Carried out by human muscle cells under Carried out by human muscle cells under oxygen debtoxygen debt..

Lactic Acid is a toxin and causes fatigue, Lactic Acid is a toxin and causes fatigue, soreness and stiffness in muscles.soreness and stiffness in muscles.

Lactic Acid FormationLactic Acid Formation

pyruvate + NADH----- lactic acid + NADpyruvate + NADH----- lactic acid + NAD++


Glucose (6 carbons)

Pyruvic Acid (3C)

Pyruvic Acid (3C)2 ATP’s supply the activation

energy

4 ATP’s are produced

4 ATP Yield = 2 ATP Net Gain

2 NAD+ + 2 e- 2 NADH 2 NAD+ + 2 e-

Lactic Acid (3C)

Lactic Acid (3C)

Glycolysis

Fermentation - SummaryFermentation - Summary

Releases 2 ATP from the breakdown Releases 2 ATP from the breakdown of a glucose moleculeof a glucose molecule

Provides ATP to a cell even when OProvides ATP to a cell even when O2 2 is is

absent.absent.

Energy TallyEnergy Tally

36 ATP for aerobic vs. 2 ATP for anaerobic36 ATP for aerobic vs. 2 ATP for anaerobic

Glycolysis Glycolysis 2 ATP2 ATP

Kreb’s Kreb’s 2 ATP2 ATP

Electron TransportElectron Transport 32 ATP32 ATP 36 ATP36 ATP

Anaerobic organisms can’t be too energetic Anaerobic organisms can’t be too energetic but are important for global recycling of carbonbut are important for global recycling of carbon

Documents

Photosynthesis and Cellular Respiration Almost all plants are photosynthetic autotrophs, as are some bacteria and protists –Autotrophs generate their