Cellular RespirationCellular Respiration

Chapter 9Chapter 9

What is a calorie?What is a calorie?

The amount of energy need to raise the The amount of energy need to raise the temperature of 1 g of Htemperature of 1 g of H22O 1O 1ooC.C.

* The Calorie used on food labels is actually a kilocalorie.

* 1 g of C6H12O6 contains 3811 calories.

How do organisms release the energy How do organisms release the energy found in Cfound in C66HH1212OO66??A 3 step process called cellular respiration. These are the steps:

1. GlycolysisGlycolysis – occurs in the cytoplasm

2. Krebs CycleKrebs Cycle – occurs in the matrix of the mitochondria

3. Electron Transport chainElectron Transport chain – occurs on the inner membrane of the mitochondria

The overview of cellular respiration:The overview of cellular respiration:

What is the difference What is the difference between aerobic & between aerobic & anaerobic reactions?anaerobic reactions?

Aerobic = uses O2. The Krebs Cycle & ETC are aerobic

Anaerobic = doesn’t use O2. Glycolysis is anaerobic.

How do cellular respiration & How do cellular respiration & photosynthesis compare?photosynthesis compare?

Aerobic RespirationAerobic RespirationStep 1: GlycolysisStep 1: Glycolysis

A. Occurs in the cytoplasmB. Produces 2 ATP2 ATPC. Produces 2 NADH2 NADH

- hi energy e- that will be used by the electron transport chain (ETC)

D. Produces 2 pyruvic acid molecules2 pyruvic acid molecules- these will be used by the Krebs cycle

Aerobic RespirationAerobic RespirationStep 2: Krebs CycleStep 2: Krebs Cycle

A. Occurs in the matrix of the mitochondria

B. A.K.A the Citric Acid CycleCitric Acid Cycle because it is temporarily made during this process

C. Produces 1 ATP1 ATPD. Produces 4 NADH4 NADH

- hi energy e- that will go to the ETCE. Produces 1 FADH1 FADH22

- hi energy e- that will go to the ETCF. Releases COCO22 as a waste productwaste product

* The main job of the Krebs Cycle is to make * The main job of the Krebs Cycle is to make more hi energy e- for the ETC.more hi energy e- for the ETC.

Aerobic RespirationAerobic RespirationStep 3: Electron Transport ChainStep 3: Electron Transport Chain

A. Occurs on the inner membrane of the mitochondria.

B. ElectronsElectrons delivered by NADH & FADH2 travel down a chain of chain of

proteinsproteins. The electrons are then used to make make H H22OO. OO22 is used at this step.

C. The movement of electrons pumps HThe movement of electrons pumps H++ across the inner membrane. across the inner membrane.D. The H+ then pass through an enzyme called ATP SynthaseATP Synthase. 24 ATP are 24 ATP are

made made here. here.

Aerobic RespirationAerobic Respiration

For each molecule For each molecule of of CC66HH1212OO66, aerobic , aerobic

(cellular) respiration (cellular) respiration produces produces 36 ATP36 ATP..

Anaerobic RespirationAnaerobic Respiration

What is anaerobic respiration?What is anaerobic respiration?The process of releasing the energy in C6H12O6 without the presence of O2.

It is a two step process:1.1. GlycolysisGlycolysis – makes 2 ATP2 ATP & 2 NADH2 NADH2.2. FermentationFermentation – turns NADH back into

NAD+* Anaerobic respiration only makes 2 ATP 2 ATP

per glucose moleculeper glucose molecule.

Anaerobic RespirationAnaerobic Respiration

Step 1: GlycolysisStep 1: Glycolysis

A. Produces 2 ATP2 ATP

B. Produces 2 NADH2 NADH

C. Produces 2 pyruvic acid 2 pyruvic acid moleculesmolecules

Anaerobic RespirationAnaerobic Respiration

Step 2: FermentationStep 2: Fermentation

A. Converts the pyruvic acid into a different molecule in order to

regenerate NAD+regenerate NAD+.

B. In Alcoholic FermentationAlcoholic Fermentation, pyruvic acid is turned into alcoholalcohol & & COCO22.

C. In Lactic Acid FermentationLactic Acid Fermentation, pyruvic acid is turned into lactic lactic acid acid.

Anaerobic RespirationAnaerobic Respiration