Agenda 10/15• Finish/review guided notes (slide on what affects enzymes)– Per. 5

feedback inhibition (5 min)• Groups that did same experiments- share and discuss data and questions -

pick a rep from each group to present to class (10 minutes)– I check toothpickase lab during this

• Go through Analysis Questions and Share out group data – discuss errors, etc. (30 min.)

• Discuss experiment in lab manual (5 min)• Last call Cells Quiz

• Homework-• Enzyme lab packet due tomorrow• Enzyme Quiz tomorrow – study guided notes, animations, powerpoint,

lab• Free Response questions due Wednesday• Enzyme lab conclusion only (follow formal report rubric) due Friday

In general…

• Higher enzyme concentration (up to a certain point) = faster reaction rate

• Higher substrate concentration (up to a certain point) = faster reaction rate

• Too high/too low temp = slower reaction rate

• Too high/too low pH = slower reaction rate

• With inhibitors= slower reaction rate

Agenda 10/16• Study for Enzyme quiz while I check lab packet (5 min)• Enzyme Quiz (20 minutes)• Background of Lab in New Lab Manual (per. 5 & 6) – 5 min• Go over Cells Quiz – 5 min• Hemoglobin practice questions from Big Idea Pwpt. (slides 12-14)-

10 min• Test analysis

Homework –• Free Response questions due tomorrow• Enzyme lab conclusion only (follow formal report rubric) due

Friday• Ch. 9 Cornell Notes and concept checks due Friday 10/19• Ch. 9 online activities due Monday 10/22 8am• Quiz on Cell Respiration Monday 10/22

Agenda 10/17

• Per. 6 – last practice question from yesterday• Grade FRQ’s (15 min)• Practice Free Energy problems – 10 min• Intro cell respiration and photosynth. as reverse processes (5 min)• Discussion of Cellular Respiration pathways as redox reactions – Ch. 9

highlighted slides to 21 (15 min)

Homework – • For tomorrow – print pages 25-28 from Curriculum Framework on my

website• Enzyme lab conclusion only (follow formal report rubric) due Friday• Ch. 9 Cornell Notes and concept checks due Friday 10/19• Ch. 9 online activities due Monday 10/22 8am (1 ½ hours)• Open-poster Quiz on Cell Respiration Monday 10/22

Bozeman Biology – great podcasts• http://www.youtube.com/watch?v=DPjMPeU5Oe

M&feature=relmfu (start at 5 ½ minutes)

Practice problems (chemistry based, scroll to bottom of first one)

• http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch21/problems/ex21_6s.html

• http://129.123.92.202/biol3300-stark/Biol3300/documents/practice/gibbs.pdf (problems that give delta G’s)

Agenda 10/18

• Cell respiration posters – memorize as you go• Cell Respiration VHS video? (1-3 through glycolysis, 4 is

Kreb’s, 5 is ETC) – did not show

Homework - • Enzyme lab conclusion only (follow formal report

rubric) due tomorrow• Ch. 9 Cornell Notes and concept checks due tomorrow• Ch. 9 online activities due Monday 10/22 8am• Open-poster Quiz on Cell Respiration Monday 10/22

Agenda 10/19• Collect enzyme lab conclusions• Using poster and my slides, we go over cellular

respiration• Discuss and sum up cell respiration with your partner –

quiz each other- I check Ch. 9 Notes during this

• Practice Quiz

Homework –• Ch. 9 online activities due Monday 10/22 8am• Open-poster Quiz on Cell Respiration Monday 10/22

– NOTE – Poster itself will be checked but not graded

f. Cellular respiration in eukaryotes involves a series of coordinated enzyme-catalyzed reactions that harvest free energy from simple carbohydrates.

1. Glycolysis rearranges the bonds in glucose molecules, releasing free energy to form ATP from ADP and inorganic phosphate, and resulting in the production of pyruvate.

Figure 9.8

Energy Investment Phase

Glucose

2 ADP 2 P

4 ADP 4 P

Energy Payoff Phase

2 NAD+ 4 e 4 H+

2 Pyruvate 2 H2O

2 ATP used

4 ATP formed

2 NADH 2 H+

NetGlucose 2 Pyruvate 2 H2O

2 ATP

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

4 ATP formed 2 ATP used

Electron shuttlesspan membrane

MITOCHONDRION2 NADH

2 NADH 2 NADH 6 NADH

2 FADH2

2 FADH2

or

2 ATP 2 ATP about 26 or 28 ATP

Glycolysis

Glucose 2 Pyruvate

Pyruvate oxidation

2 Acetyl CoACitricacidcycle

Oxidativephosphorylation:electron transport

andchemiosmosis

CYTOSOL

Maximum per glucose:About

30 or 32 ATP

Moving into matrix – on your picture, point to matrix, cristae, inner mitochondrial membrane, and intermembrane space

NADH from glycolysis – 1.5 ATP vs. 2.5 ATP per NADH depending on which shuttle working

Figure 9.10

Pyruvate

Transport protein

CYTOSOL

MITOCHONDRION

CO2 Coenzyme A

NAD + HNADH Acetyl CoA

1

2

3

2. Pyruvate is transported from the cytoplasm to the mitochondrion, where further oxidation occurs.

Figure 9.12-8

NADH

1

Acetyl CoA

CitrateIsocitrate

-Ketoglutarate

SuccinylCoA

Succinate

Fumarate

Malate

Citricacidcycle

NAD

NADH

NADH

FADH2

ATP

+ H

+ H

+ H

NAD

NAD

H2O

H2O

ADP

GTP GDP

P i

FAD

3

2

4

5

6

7

8

CoA-SH

CO2

CoA-SH

CoA-SH

CO2

Oxaloacetate

3. In the Krebs cycle, carbon dioxide is released from organic intermediates ATP is synthesized from ADP and inorganic phosphate via substrate level phosphorylation and electrons are captured by coenzymes.

Figure 9.11Pyruvate

NAD

NADH

+ HAcetyl CoA

CO2

CoA

CoA

CoA

2 CO2

ADP + P i

FADH2

FAD

ATP

3 NADH

3 NAD

Citricacidcycle

+ 3 H

Electron shuttlesspan membrane

MITOCHONDRION2 NADH

2 NADH 2 NADH 6 NADH

2 FADH2

2 FADH2

or

2 ATP 2 ATP about 26 or 28 ATP

Glycolysis

Glucose 2 Pyruvate

Pyruvate oxidation

2 Acetyl CoACitricacidcycle

Oxidativephosphorylation:electron transport

andchemiosmosis

CYTOSOL

Maximum per glucose:About

30 or 32 ATP

Now moving to the inner mitochondrial membrane

4. Electrons that are extracted in the series of Krebs cycle reactions are carried by NADH and FADH2 to the electron transport chain.

g. The electron transport chain captures free energy from electrons in a series of coupled reactions that establish an electrochemical gradient across membranes.

1. Electron transport chain reactions occur in chloroplasts (photosynthesis), mitochondria (cellular respiration) and prokaryotic plasma membranes.

Figure 9.13NADH

FADH2

2 H + 1/2 O2

2 e

2 e

2 e

H2O

NAD

Multiproteincomplexes

(originally from NADH or FADH2)

III

III

IV

50

40

30

20

10

0

Fre

e e

ner

gy

(G)

rela

tiv

e to

O2 (

kcal

/mo

l)

FMN

FeS FeS

FAD

Q

Cyt b

Cyt c1

Cyt c

Cyt a

Cyt a3

FeS

2. In cellular respiration, electrons delivered by NADH and FADH2 are passed to a series of electron acceptors as they move toward the terminal electron acceptor, oxygen.

The electrons carried by FADH2 have lower free energy and are added to a later point in the chain.

• 3. The passage of electrons is accompanied by the formation of a proton gradient across the inner mitochondrial membrane or the thylakoid membrane of chloroplasts, with the membrane(s) separating a region of high proton concentration from a region of low proton concentration. In prokaryotes, the passage of electrons is accompanied by the outward movement of protons across the plasma membrane.

Figure 9.15

Proteincomplexof electroncarriers

(carrying electronsfrom food)

Electron transport chain

Oxidative phosphorylation

Chemiosmosis

ATPsynth-ase

I

II

III

IVQ

Cyt c

FADFADH2

NADH ADP P i

NAD

H

2 H + 1/2O2

H

HH

21

H

H2O

ATP

4. The flow of protons back through membrane-bound ATP

synthase by chemiosmosis generates ATP from ADP and

inorganic phosphate.

• ATP synthase uses the exergonic flow of H+ to drive phosphorylation of ATP

• This is an example of chemiosmosis, the use of energy in a H+ gradient to drive cellular work

• The H+ gradient is referred to as a proton-motive force, emphasizing its capacity to do work

Figure 9.14INTERMEMBRANE SPACE

Rotor

StatorH

Internalrod

Catalyticknob

ADP+P i ATP

MITOCHONDRIAL MATRIX

– As hydrogen ions flow down their gradient, they cause the rotor to rotate.

– The spinning rod causes a conformational change in the knob region, activating catalytic sites where ADP and inorganic phosphate combine to make ATP.

INTERMEMBRANE SPACE

Rotor

StatorH

Internalrod

Catalyticknob

ADP+P i ATP

MITOCHONDRIAL MATRIX

Figure 9.16

Electron shuttlesspan membrane

MITOCHONDRION2 NADH

2 NADH 2 NADH 6 NADH

2 FADH2

2 FADH2

or

2 ATP 2 ATP about 26 or 28 ATP

Glycolysis

Glucose 2 Pyruvate

Pyruvate oxidation

2 Acetyl CoACitricacidcycle

Oxidativephosphorylation:electron transport

andchemiosmosis

CYTOSOL

Maximum per glucose:About

30 or 32 ATP

5. In cellular respiration, decoupling oxidative phosphorylation from electron

transport is involved in thermoregulation.

• Used by hibernating mammals• Brown fat, high in mitochondria, with ETC

uncoupling protein– Protein is activated during hibernation– Allows protons to flow back down their gradient

without making ATP (uncoupled)– Ongoing oxidation of stored fuel generates heat to

keep body temp warmer than environment– If ATP were made, would build up to high levels that

would shut down the cell respiration pathways

Fermentation produces organic molecules, including alcohol and lactic acid, and it occurs in the absence of oxygen.

See Ch. 9 slide 78 Animation

• In alcohol fermentation, pyruvate is converted to ethanol in two steps.– First, pyruvate is converted to a two-carbon

compound, acetaldehyde by the removal of CO2.

– Second, acetaldehyde is reduced by NADH to ethanol.

– Alcohol fermentation by yeast is used in brewing and winemaking.

Fig. 9.17a

• During lactic acid fermentation, pyruvate is reduced directly by NADH to form lactate (ionized form of lactic acid). – Lactic acid fermentation by some fungi and

bacteria is used to make cheese and yogurt.– Muscle cells switch from aerobic respiration to

lactic acid fermentation to generate ATP when O2 is scarce.• The waste product,

lactate, may cause muscle fatigue, but ultimately it is converted back to pyruvate in the liver.

Fig. 9.17b

• Some organisms (facultative anaerobes), including yeast and many bacteria, can survive using either fermentation or respiration.

• At a cellular level, human muscle cells can behave as facultative anaerobes, but nerve cells cannot.

• For facultative anaerobes, pyruvate is a fork in the metabolic road that leads to two alternative routes.

Fig. 9.18

The Evolutionary Significance of Glycolysis

• Ancient prokaryotes are thought to have used glycolysis long before there was oxygen in the atmosphere

• Very little O2 was available in the atmosphere until about 2.7 billion years ago, so early prokaryotes likely used only glycolysis to generate ATP

• Glycolysis is a very ancient process

© 2011 Pearson Education, Inc.

• Control of catabolism is based mainly on regulating the activity of enzymes at strategic points in the catabolic pathway.

• One strategic point occurs in the third step of glycolysis, catalyzed by phosphofructokinase.

Fig. 9.20

• Carbohydrates, fats, and proteins can all be catabolized through the same pathways.

Fig. 9.19

Let’s Practice Quiz

• Use your poster and follow along as I ask a few example questions.

• Then continue this with your neighbor.