All organisms need energy

Why do we need energy?

To Grow

To Move

To Reproduce

ETC.

Respiration provides energy from food

The energy carrier of all cells

ATP PRODUCTION

Intermediate Electron Carriers:Nads and fads

NADH

Nicotinamide adenine

dinucleotide

NAD + H NADH

FADH2

Flavin adenine dinucleotide

FAD + 2H FADH2

• Aerobic respiration requires oxygen

• Anaerobic respiration does not require oxygen

Anaerobic Respiration• No oxygen is needed.• Some small organisms do this.• Other cells that do this include

human muscle cells during times of low oxygen.

• Fermentation often follows.• Glycolysis occurs in all cells.• Provides only a little energy – 2 ATP net gain.

NEEDS

2 ATP

1 GLUCOSE

2 NAD

4 ADP+4P

RELEASES

2adp + 2p

2 PYRUVATE

2 NADh

4 ATP

• Occurs in cytoplasm of all cells.• Breaks down glucose incompletely.• Provides the cell with a net gain of only

2 ATP.• Is often followed by fermentation.

anAerobic Respiration (Glycolysis) can be

followed by Fermentation

• Muscle cells – further break down pyruvate into lactic acid – but this doesn’t provide any additional ATP. – Lactic acid is toxic and causes muscle aches.

When the physical exertion ends (you collapse), your body will clear itself of the toxins.

Yeast carry out Alcoholic Fermentation

• After glycolysis, yeast further breaks down pyruvate to CO2 and alcohol. – The CO2 bubbles off (making bread rise and

bubbles in drinks).

– The alcohol is given off by the yeast as a waste.

C6H12O6 + 6O2 6CO2 + 6H2O + ATP

Glucose + oxygen carbon dioxide + water + ATP

Aerobic Respiration Equation

Aerobic Respiration has three major steps

• 1

• 2

• 3 34-36 ATP

The Krebs Cycle

Needs

2 FAD

6 NAD

Pyruvate

2ADP + 2P

RELEASES

2 FADH2

6 NADH

CO2

2ATP

Electron Transport chain (ETc)

Occurs on the cristae of the

mitochondrion

The Electron Transport chain

Needs

2 FADH2

10 NADH

O2

ADP + P

Releases

FAD

NAD

H2O

Up to 34 ATP

Final ATP TallyStage NADH FADH2 ATP Yield

Glycolysis 2 2Pyruvic acid conversion

2

Krebs cycle 6 2 2ETC 10 32-34Loss due to active transport

-2

Total ATP 36-38

Respiration provides Energy from food so we

can:

The end