LB145Sec 001-004

Happy Valentine’s Day!

Today’s Announcements• StudyNotes5 AND Homework4 are due on

Tuesday Feb 19th. • **Download HW VERSION 2.0**• Field Trip sign up – started!• Glycolysis and the Krebs Cycle.• Oxidative Phosphorylation, the ETC.

Glyc

olys

is: W

hat d

o yo

u ne

ed to

kno

w? Track the Carbons and Phosphates:

Glucose + ATP Fructose-P + ADP

Fructose-P + ATP P-Fructose-P

P-Fructose-P P-CCC + P-CCC

P-CCC + P-CCC + 2NAD+ + 2Pi P-CCC-P + P-CCC-P + 2NADH

P-CCC-P + P-CCC-P + 2ADP P-CCC + P-CCC + 2ATP

P-CCC + P-CCC + 2ADP Pyruvate + Pyruvate + 2ATP

Methods of Producing ATP

GLYCOLYSIS & CITRIC ACID CYCLE• Substrate-level phosphorylation occurs when ATP is

produced by the enzyme-catalyzed transfer of a phosphate group from an intermediate substrate to ADP.

Campbell: Fig. 9-6-3

Mitochondrion

Substrate-levelphosphorylation

ATP

Cytosol

Glucose Pyruvate

Glycolysis

Electronscarried

via NADH

Substrate-levelphosphorylation

ATP

Electrons carriedvia NADH and

FADH2

Oxidativephosphorylation

ATP

Citricacidcycle

Oxidativephosphorylation:electron transport

andchemiosmosis

Fig. 9-10

CYTOSOL MITOCHONDRION

NAD+ NADH + H+

2

1 3

Pyruvate

Transport protein

CO2Coenzyme A

Acetyl CoA

Fig. 9-11

Pyruvate

NAD+

NADH+ H+

Acetyl CoA

CO2

CoA

CoA

CoA

Citricacidcycle

FADH2

FAD

CO22

3

3 NAD+

+ 3 H+

ADP + P i

ATP

NADH

Bitter MelonSelling my Body to Science1. Consume a cup of liquid glucose.2. Consume capsules that contain

bitter melon OR placebo.3. Lie still on a bed with a dome

over my head and allow breath to be analyzed for an hour.

QUESTIONS:Q1: On a molecular level, what is happening if bitter melon aids weight

loss?Q2: On a molecular level, what is happening if bitter melon does not aid

weight loss?Q3: Why were they interested in the air I exhaled?Q4: What do you think might happen to excess glucose in your body?

Glycolysis is a core metabolic pathway!

Campbell 8e Fig. 9.16

How does this

compare to light

reactions?

ETC: The main pieces

Complex I: NADH dehydrogenase• removes e- from NADH• pumps 4 H+ into inter-

membrane space

Complex II: succinate dehydrogenase• moves e- from FADH2 to Q

Complex III: Cytochrome bc1

• transfers e- from Q to Cyt c• pumps 2 H+ into intermembrane space

Complex IV: cytochrome c oxidase• transfers e- from Cyt c to O2

• pumps 2H+ into intermembrane space

Q: ubiquinone, pumps 2 H+ into intermembrane space

Cyt c: cytochrome c• e- shuttles

Disrupting cellular respiration:What happens if…..?

Disrupting cellular respiration:What happens if…..?

• Cyanide– Binds to Cytochrome oxidase

(Complex IV)

– Immediate Effect?

– Ultimate Effect?

Disrupting cellular respiration:What happens if…..?

• Rotenone– Binds to ubiquinone binding site of

Complex I

– Immediate Effect?

– Ultimate Effect?

Disrupting cellular respiration:What happens if…..?

• Dinitrophenol– Protonophore (makes membrane

completely permeable to H+ ions)

– Immediate Effect?

– Ultimate Effect?

Anaerobic Respiration

Anaerobic Respiration(from wikipedia)

Homework Problem:Question: The Glucose Problem In the molecular process known as cellular respiration, how many ATP molecules can be made from the electron transport chain after one molecule of glucose is catabolized in glycolysis, pyruvate processing and the citric acid cycle. Assume that 1 ATP is produced when 3.5 protons pass through ATP synthase.

**What pieces of information do I need to know to solve

this problem?

Problem solving…

Problem solving…What would be the implications if a

mitochondria was missing Complex II?

Problem solving…If Complex I was missing, what would net more

ATP: Krebs Cycle OR ETC?

Problem solving…Can the ETC make energy (ATP) when we are not

breathing? Why or why not?

Problem solving…Assume there was an unlimited supply of readily

available NADH and an unlimited supply of readily available photons. If you had to choose one of the below two processes to make ATP,

which would you choose (and why!)

For TUESDAY:1. SN5 and HW4 (Version 2.0)2. Honors Option Students – SIGN UP FOR THE

FIELD TRIP (and show me the money)