Respiration

A Dr. Production

Energy Concepts

• Thermodynamics & Reaction Rates

• RESPIRATION a process where organic (food) molecules are oxidized & broken down to release E

• Glycolysis is the 1o source of e- for the citric acid and e- transport chain

• CH2O + O2 CO2 + H2O + Energy

• Has both an anaerobic phase and an aerobic phase

• Associated with Mitochondria found in eukaryotic cells

• Respiration is a multi-step process that occurs in several places in the mitochondria. So it is important that you know the anatomy of the mitochondria

Glyco lysis, or "splitting of sugar" occurs in the cytosolGlucose is very stable, and must be converted to reactive

compound by phosphorylation Glucose (6C)

2ATP

2ADP + 2P

PGAL (3C) PGAL (3C)

NAD+ NAD+

NADH NADH

 2ADP + 2P 2ADP + 2P

2ATP 2ATP

  Pyruvic Acid (3C) Pyruvic Acid (3C)

Redox Reactions

• How NAD+ Works

Glycolysis

• net gain +2ATP, 2% total E in 1 molecule glucose, only 7% of E released

• 2ADP 2ATP

• 2NAD+ 2NADH + 2H+

• 1 Glucose 2Pyruvate

Pyruvic Acid vs Pyruvate

Draw pyruvate

Conversion of Pyruvate• Conversion of Pyruvate occurs in the mitochondrial

membrane

Identify the components of Acetyl CoA

TCA/Citric Acid/Krebs Cycle

• Citric Acid Cycle occurs in the mitochondrial matrix

• each molecule acetyl Co-A yields the following from one molecule of glucose:

3NADH+ + H +

1FADH2

1ATP

2CO2

Or, for a more detailed look…

The Electron Transport Chain

E- Transport Chain occurs across the inner mitochondrial membrane and in the inter-membrane space

It uses O2 to transfer e- from 10NADH + H+ and 2FADH2

It separates H into e- and H+, carries e- away from H+ gradient

Which side is more basic than the other?

More acidic?

More alkaline?

ATPase attached to H + channels and uses kinetic E of H+ to join ADP + P this is called "chemiosmotic ATP synthesis"

each NADH+ + H + produces 3ATP = 30 ATP

each FADH2 produces 2ATP = 4 ATP

Glycolysis = 2 ATP

Kreb’s Cycle = 2 ATP

ATP Synthetase The Movie

Electron Transporters

Got O2?

• In the absence of O2…

• Fermentation occurs…

Pyruvate (3C) Pyruvate (3C)

CO2

Acetaldehyde (2C)

NADH + H+ NADH + H+

NAD+ NAD+

Ethanol Lactic Acid

Liver

Glucose Glycogen in the liver is a reserve of glucose.

When blood sugar levels drop below 4 to 5 mM glycogen phosphorylase is activated

• Fermentation generates 0ATP, so what is it’s usefulness?

• How did the first anaerobic heterotrophs make E?

• NAD+ is needed for glycolysis

• Pyruvic acid generates NADH from NAD+, fermentation regenerates NAD+

• Which is more efficient, aerobic or anaerobic respiration? What is the evolutionary significance of this?

Alternative Energy Sources for Muscles

• Hydrolysis of Sucrose in Intestines

• Fatty Acid Metabolism

RESPIRATIONRESPIRATION CYTOPLASM CYTOPLASM GLYCOLOSIS GLYCOLOSIS

HAPPENS HERE!HAPPENS HERE!

MITOCHONDRIAMITOCHONDRIARESPIRATION HAPPENS IN RESPIRATION HAPPENS IN

THIS ORGANELLE!THIS ORGANELLE!

PROTEINSPROTEINS CARBO’SCARBO’S(SUGARS)(SUGARS)

AMINOAMINOACIDSACIDS

FATSFATS(LIPIDS)(LIPIDS)

GLUCOSEGLUCOSECC66HH1212OO66

ACETYL-CoAACETYL-CoA

PYRUVICPYRUVICACIDACID

GLYCOLOSISGLYCOLOSISIN CYTOPLASM IN CYTOPLASM

NO OXYGEN!NO OXYGEN!

KREBS CYCLEKREBS CYCLE AND AND

ELECTRONELECTRONTANSPORTTANSPORT

MAKESMAKES34 ATPS34 ATPS

MAKESMAKES2 ATPS2 ATPS

OO2 2 ENTERS ENTERS HEREHERE

COCO22 IS IS RELEASEDRELEASED

ATP TOTALSATP TOTALS

GLYCOLOSIS=2GLYCOLOSIS=2

RESPIRATION=34RESPIRATION=34

BOTH=36!BOTH=36!

Gluconeogenesis• Gluconeogenesis is the synthesis of glucose from non-carbohydrate

sources. Glucose must be synthesized after 12-24 hours of fasting or during prolonged exercise to maintain blood glucose concentration.

• The brain prefers to use glucose as fuel, although after a long period of starvation it can derive some of its energy requirements from ketone bodies.

• RBCs have an absolute requirement for glucose since they have no mitochondria and can not utilize ketone bodies.

• Occurs in the liver (& kidney cortex after prolonged starvation), in cytosol &mitochondria.

Glycolysis Pyruvate Intermediate

TCA Cycle E- Transport Chain

Fermen-tation

Where it occurs

Co-Enzymes used

Co-Enzymes produced

ATP Used

ATP Produced

MISC Inputs

MISC Outputs

References• Hibernation:

• Krebs cycle Tutorial

• Citric Acid Cycle tutorial

• A&P Animations & Quizzes

• ATP & Energy Storage

• Fermentation & Irritable Bowel Syndrome

• Step by Step Glycolysis

• Interactive Biochemistry Animations

• Overview of Glycolysis Heavy Chemistry

• Fundamentals of Biochemistry Animations

• Glycolysis with Redox Reactions

• Cellular Respiration Animation: Summary