chapter 9: cellular respiration: harvesting chemical energy -transport – tuesday -test info -avg =...

Chapter 9: Cellular Respiration: Harvesting Chemical Energy

-Transport – Tuesday -Test info

-AVG = 22 (Mercer’s class as well) -Range = 9 – 32

-Most missed questions-A B-16 13 (98 of 122)-18 14 (99 of 122)-20 30 (89 of 122)-28 6 (105 of 122)

-Learning log quality has declined….changes coming-Ignored cues -Verbatim answers from yahoo answers, et al = learning-Direct contradictions from earlier units….no retention-Reading comprehension issues & questions not fully answered

Bennett students-Lab notebooks onto cart by computer station

-1st – top shelf-2nd – 2nd shelf-4th – top shelf

Mercer’s students-Any needs? He will attend to on Monday-Food items – take to his room & log into notebook-Need someone to help with attendance…thank you!

ALL students-Test corrections due Monday-Clean up after yourselves when leaving please-Cell phones into bin – muted or off – please & thank you!

Welcome to AP Biology College Lecture Hall!!!- Participation is important – NO social loafing!

What do you know about Cellular Respiration?

1. Why is respiration important?- Consumption of food & oxygen to produce CO2, water & energy

- C6H12O6 + 6O2 6CO2 + 6H2O + energy (ATP + heat)


Light energy

ECOSYSTEM

CO2 + H2O

Photosynthesisin chloroplasts

Cellular respiration

in mitochondria

Organicmolecules

+ O2

ATP

powers most cellular work

Heatenergy

1. Why is respiration important?- Consumption of food & oxygen to produce CO2, water & energy


- Exergonic rxn releases -686 kcal/mol using redox rxns

- All foods can be metabolized as fuel (carbs, proteins, fats,)


1. Why is respiration important?

2. What are redox rxns?- Reduction & oxidation

- LEO says GER

- Loss of Electrons – Oxidation : Gain of Electrons – Reduction

- ┌----oxidation-----┐


- └----reduction----┘



2. What are redox rxns?

3. What are the 3 main steps of respiration?- Glycolysis

- Citric Acid Cycle (Krebs Cycle)

- Oxidative Phosphorylation - Electron Transport Chain (ETC)- Chemiosmosis



Electronscarried

via NADH

Glycolysis

Glucose Pyruvate

ATP

Substrate-levelphosphorylation

Electrons carried via NADH and

FADH2

Citric acid cycle

Oxidativephosphorylation:electron transport

andchemiosmosis

ATPATP

Substrate-levelphosphorylation

Oxidativephosphorylation

Mitochondrion



3. What are the 3 main steps of respiration?

4. What happens during glycolysis?- Glucose is split in the cytosol- 10 steps- NO oxygen needed



Glycolysis Citricacidcycle


ATP ATP ATP

2 ATP

4 ATP

used

formed

Glucose

2 ADP + 2 P

4 ADP + 4 P

2 NAD+ + 4 e- + 4 H + 2 NADH + 2 H+

2 Pyruvate + 2 H2O

Energy investment phase

Energy payoff phase

Glucose 2 Pyruvate + 2 H2O

4 ATP formed – 2 ATP used 2 ATP

2 NAD+ + 4 e– + 4 H + 2 NADH + 2 H+




4. What happens during glycolysis?

5. How is the ATP made in glycolysis?- Substrate-level phosphorylation – ATP produced from the transfer of a

phosphate group from a substrate to ADP- ATP made one at a time


Enzyme Enzyme

ATP

ADP

Product

SubstrateP

+





5. How is the ATP made?

6. How do electrons get from glucose to O2?- NAD+ - nicotinamide adenine dinucleotide- Coenzyme (derived from niacin, a vitamin)- Accepts 2 e- and a H+


NAD+

H

O

O

O O–

O

O O–

O

O

O

P

P

CH2

CH2

HO OHH

HHO OH

HO

H

H

N+

C NH2

HN

H

NH2

N

N

Nicotinamide(oxidized form)

NH2+ 2[H]

(from food)

Dehydrogenase

Reduction of NAD+

Oxidation of NADH

2 e– + 2 H+

2 e– + H+

NADH

OH H

N

C +

Nicotinamide(reduced form)

N

H+

H+







6. How do electrons get from glucose to O2?

7. How does pyruvate get into the mitochondria for the Krebs Cycle?

- Active transport across double membrane- 3 step process


CYTOSOL MITOCHONDRION

NADH + H+NAD+

2

31

CO2 Coenzyme APyruvate

Acetyl CoA

S CoA

C

CH3

O

Transport protein

O–

O

O

C

C

CH3


1. Why is respiration important?2. What are redox rxns?3. What are the 3 main steps of respiration?4. What happens during glycolysis?5. How is the ATP made?6. How do electrons get from glucose to O2?7. How does pyruvate get into the mitochondria for the Krebs

Cycle?8. What happens during the Citric Acid Cycle?

- Mitochondrial matrix- 8 steps- Spins 2X per glucose (1X for each pyruvate)


NAD+

ATP

2 CO2

3 NAD+

3 NADH

+ 3 H+

ADP + P i

FAD

FADH2

Citricacidcycle

CoA

CoA Acetyl CoA

NADH

+ H+

CoA

CO2

Pyruvate(from glycolysis,2 molecules per glucose)

ATP ATP ATP

Glycolysis Citricacidcycle



1. Why is respiration important?2. What are redox rxns?3. What are the 3 main steps of respiration?4. What happens during glycolysis?5. How is the ATP made?6. How do electrons get from glucose to O2?7. How does pyruvate get into the mitochondria for the Krebs

Cycle?8. What happens during the Citric Acid Cycle?9. How many ATP so far?

- 4 total, 2 from glycolysis & 2 from Krebs Cycle- ALL from substrate-level phosphorylation









8. What happens during the Citric Acid Cycle?

9. How many ATP so far?

10. How many electron carriers so far?

- 10 NADH

- 2 FADH2


Test corrections -Stapled BEHIND test-Place in box

-Lab notebooks – give to me

-Current learning log – on-line-Transport tomorrow

-This week-Mon – Ch 9-Tues – Finish Ch 9 & begin Case Study-Wed – Finish Case Study-Thurs – Lab – Respiration – Dress up for Halloween???-Fri – OFF….for you

-Cell phones in bin – muted or off….please & thank you

1. Why is respiration important?2. What are redox rxns?3. What are the 3 main steps of respiration?4. What happens during glycolysis?5. How is the ATP made?

6. How do electrons get from glucose to O2?7. How does pyruvate get into the mitochondria for the Krebs

Cycle?8. What happens during the Citric Acid Cycle?9. How many ATP so far?10. How many electron carriers so far?11. What happens during electron transport?

- redox rxns in inner mitochondrial membrane

- electrons flow from electron carriers to electronegative O2

- electron carriers “break the fall”

12. Why do electron carriers NEED to “break the fall?”


H2 + 1/2 O2 2 H 1/2 O2

(from food via NADH)

2 H+ + 2 e–

2 H+

2 e–

H2O

1/2 O2

Controlled release of energy for synthesis of

ATPATP

ATP

ATP

Electro

n tran

spo

rt chain

F

ree

ener

gy, G

(b) Cellular respiration(a) Uncontrolled reaction

Fre

e en

ergy

, G

H2O

Explosiverelease of

heat and lightenergy

+


Glycolysis Citircacidcycle


ATP ATP ATP

H2O

O2

NADH

FADH2

FMN

Fe•S Fe•S

Fe•S

O

FAD

Cyt b

Cyt c1Cyt c

Cyt aCyt a3

2 H + + 12

III

III

IV

Multiproteincomplexes

0

10

20

30

40

50

Fre

e e

ne

rgy

(G)

rela

tive

to

O2 (k

cl/m

ol)

Figure 9.13 Free-energy change during electron transport

-Redox reactions between each carrier-Each carrier is more electronegative

than the previous one-O2 is the final electron acceptor-Protons are pumped to the

inner membrane space











11. What happens during electron transport?

12. Why do electrons NEED to “break the fall?”

13. How is ATP made during chemiosmosis?


MITOCHONDRIAL MATRIX

INTERMEMBRANE SPACE

H+

H+

H+

H+

H+

H+ H+

H+

P i

+ADP

ATP

A rotor within the membrane spins clockwise whenH+ flows pastit down the H+

gradient.

A stator anchoredin the membraneholds the knobstationary.

A rod (or “stalk”)extending into the knob alsospins, activatingcatalytic sites inthe knob.

Three catalytic sites in the stationary knobjoin inorganic Phosphate to ADPto make ATP.

Figure 9.14 ATP synthase, a molecular mill


electron transportand chemiosmosis

Glycolysis

ATP ATP ATP

InnerMitochondrialmembrane

H+

H+H+

H+

H+

ATPP i

Protein complexof electron carners

Cyt c

I

II

III

IV

(Carrying electronsfrom food)

NADH

FADH2

NAD+

FAD+ 2 H+ + 1/2 O2

H2O

ADP +

Electron transport chainElectron transport and pumping of protons (H+),

which create an H+ gradient across the membrane

ChemiosmosisATP synthesis powered by the flowOf H+ back across the membrane

ATPsynthase

Q

Oxidative phosphorylation

Intermembranespace

Innermitochondrialmembrane

Mitochondrialmatrix

Citircacidcycle

Figure 9.15 Chemiosmosis couples the electron transport chain to ATP synthesis

1 NADH = 2.5 ATP1 FADH2 = 1.5 ATP

Figure 9.16 ATP yield per molecule of glucose at each stage of cellular respiration














14. What happens when there is no O2?

- anaerobic respiration (fermentation)


Glucose

CYTOSOL

Pyruvate

No O2 presentFermentation

O2 present Cellular respiration

Ethanolor

lactate

Acetyl CoA

MITOCHONDRION

Citricacidcycle

Figure 9.18 Pyruvate as a key juncture in catabolism

2 ADP + 2 P i 2 ATP

GlycolysisGlucose

2 NAD+ 2 NADH

2 Pyruvate

2 Acetaldehyde2 Ethanol

(a) Alcohol fermentation

2 ADP + 2 P i 2 ATP

GlycolysisGlucose

2 NAD+ 2 NADH

2 Lactate

(b) Lactic acid fermentation

H

H OH

CH3

C

O–

OC

C O

CH3

H

C O

CH3

O–

C O

C O

CH3O

C O

C OHH

CH3

CO22

2 Pyruvate

+2 H+

Figure 9.17 Fermentation














14. What happens when there is no O2?

15. How do the other foods we eat get catabolized?


Amino acids

Sugars Glycerol Fattyacids

Glycolysis

Glucose

Glyceraldehyde-3- P

Pyruvate

Acetyl CoA

NH3

Citricacidcycle


FatsProteins Carbohydrates

Figure 9.19 The catabolism of various molecules from food

Fats - Even numbered fatty acid chains- Beta oxidation – catabolized to 2-carbon units

1. Why is respiration important?2. What are redox rxns?3. What are the 3 main steps of respiration?4. What happens during glycolysis?5. How is the ATP made?

6. How do electrons get from glucose to O2?7. How does pyruvate get into the mitochondria for the Krebs Cycle?8. What happens during the Citric Acid Cycle?9. How many ATP so far?10. How many electron carriers so far?11. What happens during electron transport?12. Why do electrons NEED to “break the fall?”13. How is ATP made during chemiosmosis?

14. What happens when there is no O2?15. How do the other foods we eat get catabolized?16. How is cellular respiration controlled?


Glucose

Glycolysis

Fructose-6-phosphate

Phosphofructokinase

Fructose-1,6-bisphosphateInhibits Inhibits

Pyruvate

ATPAcetyl CoA

Citricacidcycle

Citrate


Stimulates

AMP

+

– –

Figure 9.20 The control of cellular respiration

-Allosteric regulation of PFK Phosphofructokinase-ATP & Citrate allosteric inhibitors-AMP allosteric activator

Students-Pick up handout – Case Study

-Transport today

-We are in Mercer’s classroom tomorrow

-Cell phones in bin – off or muted – please & thank you

Story timeGlucose RespirationGlycolysis ShuttleRefrigerator NADH & NAD+

Book MovingATP Mr. Bennett or AllanProcess BlondePyruvate RedoxOxygen Electron Pen PhosphofructokinaseCitric acid cycleChemiosmosisATP synthaseH+

WaterElephant Turtle

Students…please get:- ½ sheet handout- Learning logs from 1st table

-Turn in “Respiration Stories” to box

-Transport - TODAY

Respiration Pictographs

Today you will construct pictographs on the topics listed below. Your groups will create this pictograph using a fun & creative example to tell the story of the process. Your pictograph will include where each process occurs, who the main players are, and what their role is. Then EACH of you will write a paragraph indicating how each of your symbols from the pictograph represents the biology of the process. You will present these pictographs tomorrow.

Topics:Glycolysis (Figure 9.8)Citric Acid Cycle (Figure 9.11)Oxidative Phosphorylation: Electron Transport (Fig. 9.13 & 9.15)Oxidative Phosphorylation: Chemiosmosis (Figure 9.14 & 9.15) Anaerobic respiration (Figure 9.17)

Announcements-Transport – today – all day & 4:30-Pre-Lab – tomorrow

-Lab 5: Cellular Respiration -Using mealworms instead of peas

-Get lab notebook -Checked for “turned in”-Content check later

-If I have jury duty-1st, 4th, & 7th periods – meet in Mr. Mercer’s room-2nd & 3rd – meet in Media Center

-Absent1 2 4 7-Sarah M. Jillian Autumn Jamese-David-Katherine

chapter 9: cellular respiration: harvesting chemical energy -transport – tuesday -test info -avg =...

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