Cellular RespirationChapter 8.3

Animal

Plant

Mitochondria

Cellular Respiration Catabolic pathway Organic sugars are broken down to

release energy for the cell Electrons are used for energy (opposite of photosynthesis)

C6H12O6 + 6 O2 6 CO2 + 6 H2O

Question Which cell organelle makes energy

available to the rest of the cell? Mitocondria – energy powerhouse

Cellular RespirationGlycolysi

sKrebs Cycle

Electron Transpor

t

Anaerobic:

Does not require oxygen

Aerobic:Requires oxygen

Outer membrane Intermembrane space

Inner membrane

Matrix

Mitochondria

Glycolysis What are the reactants

in this process? Glucose, 2 ATP, 2 NAD+

and 4 ADP What are the products

of this process? 2 ADP, 2 NADH, 4 ATP,

and 2 pyruvates

Glycolysis Overall Purpose:

Initial break down of GLUCOSE to release energy

Produces ATP and NADH molecules for energy storage

Takes place in the…. CYTOPLASM

Reactants: Glucose (ADP & NAD+)

Products: Two PYRUVATE molecules (ATP & NADH)

Krebs Cycle (Citric Acid Cycle) Overall Purpose:

In the presence of oxygen, pyruvate is broken down to carbon dioxide (CO2)

Collect energized electrons to pass to the electron transport chain (NADH/FADH2 carriers)

Takes place in the…. MITOCHONDRIAL MATRIX

Reactants: Pyruvate (ADP, NAD+, & FAD)

Products: CO2

(ATP, NADH, & FADH2)

Overall Purpose: High-energy electrons and hydrogen ions from NADH and

FADH2 are used to convert ADP to ATP Electrons from NADH and FADH2 are passed to the electron

transport chain Oxygen picks up the electrons (and hydrogen) to make water Hydrogen ions flow through ATP synthase to make ATP

Takes place in the…. INNER MITOCHONDRIAL MEMBRANE

Reactants: (NADH & FADH2) Oxygen

Products: (NAD & FAD) Water ATP!!!!!

Electron Transport

What about bacteria? Prokaryotic cells (bacteria)

don’t have mitochondria…

Electron transport takes place in the cell membrane!

http://www.google.com/url?sa=i&rct=j&q=cellular+respiration&source=images&cd=&cad=rja&docid=Ut7RtL0v4dHelM&tbnid=itMcU8pcDvpTJM:&ved=0CAUQjRw&url=http://zombiemechanics.com/2011/09/review-the-physics-of-zombies-iii/detailed_cellular_respiration_cycle-modified/&ei=2ootUbO8Icy60QH6wIGIDg&bvm=bv.42965579,d.dmQ&psig=AFQjCNG4zBNSwUagBfAnwYeQEZG2KKGm7g&ust=1362025532483063

Mr. Anderson’s Podcast (Bozemanbiology):

http://www.youtube.com/watch?v=Gh2P5CmCC0M

Anaerobic Respiration Cells can function for a short time with little

oxygen Cells continue to produce ATP through glycolysis

Glycolysis only produces a small amount of ATP Limited by the availability of NAD+

Anaerobic respiration that follows glycolysis is called fermentation

Fermentation occurs in the cytoplasm• Two types of

fermentation:• Lactic acid

fermentation• Alcohol

fermentation

Lactic Acid Fermentation Enzymes convert

pyruvate from glycolysis to lactic acid

Transfer of electrons from NADH

Skeletal muscles produce lactic acid when there is not enough oxygen

Bacteria make lactic acid in the production of cheese, yogurt, and sour cream from milk

Alcohol Fermentation

Occurs in yeast and some bacteria

Pyruvate is converted to alcohol and carbon dioxide

NADH transfers electrons