Cellular Respiration

When is ATP Made in the Body? During a Process called Cellular Respiration that takes place in both Plants & Animals

Cellular Respiration Occurs in 3 stages – Glycolysis (kickstart) – Krebs Cycle Also known as Citric Acid Cycle – Electron Transport Chain (ETC) Depends upon the production of high energy electron carriers (similar to photysynthesis) to produce ATP

Cellular Respiration Simplified

Cellular Respiration Includes pathways that require oxygen Includes pathways that require oxygen Glucose is oxidized and O 2 is reduced Glucose is oxidized and O 2 is reduced Glucose breakdown is therefore an oxidation-reduction reaction Glucose breakdown is therefore an oxidation-reduction reaction Breakdown of one glucose results in 36 to 38 ATP molecules Breakdown of one glucose results in 36 to 38 ATP molecules

Overall Equation for Cellular Respiration 6CO 2 + 6H e ATP’s C 6 H 12 O 6 + 6O 2 YIELDS Copyright Cmassengale

Other Cellular Respiration Facts Metabolic Pathway that breaks down carbohydrates Metabolic Pathway that breaks down carbohydrates Process is Exergonic as High-energy Glucose is broken into CO 2 and H 2 O Process is Exergonic as High-energy Glucose is broken into CO 2 and H 2 O Process is also Catabolic because larger Glucose breaks into smaller molecules Process is also Catabolic because larger Glucose breaks into smaller molecules

What are the Stages of Cellular Respiration? Glycolysis Glycolysis The Krebs Cycle The Krebs Cycle The Electron Transport Chain The Electron Transport Chain

Where Does Cellular Respiration Take Place? It actually takes place in two parts of the cell: It actually takes place in two parts of the cell: Glycolysis occurs in the Cytoplasm Krebs Cycle & ETC Takeplace in the Mitochondria Krebs Cycle & ETC Take place in the Mitochondria

Diagram of the Process Occurs in Cytoplasm Occurs in Matrix Occurs across Cristae

Glycolysis Summary Takes place in the Cytoplasm Anaerobic (Doesn’t Use Oxygen) Requires input of 2 ATP Glucose split into two molecules of Pyruvate or Pyruvic Acid

Glycolysis Summary Also produces 2 NADH and 4 ATP Also produces 2 NADH and 4 ATP Pyruvate is oxidized to Acetyl CoA and CO 2 is removed Pyruvate is oxidized to Acetyl CoA and CO 2 is removed

Glycolysis Diagrams

Fermentation Occurs when O 2 NOT present (anaerobic)  Occurs when O 2 NOT present (anaerobic)  Called Lactic Acid fermentation in muscle cells (makes muscles tired)  Called Alcoholic fermentation in yeast (produces ethanol)  Nets only 2 ATP

Krebs Cycle Summary Requires Oxygen (Aerobic) Requires Oxygen (Aerobic) Cyclical series of oxidation reactions that give off CO 2 and produce one ATP per cycle Cyclical series of oxidation reactions that give off CO 2 and produce one ATP per cycle Turns twice per glucose molecule Turns twice per glucose molecule Produces two ATP Produces two ATP Takes place in matrix of mitochondria Takes place in matrix of mitochondria

Krebs Cycle Summary Each turn of the Krebs Cycle also produces 3NADH, 1FADH 2, and 2CO 2 Each turn of the Krebs Cycle also produces 3NADH, 1FADH 2, and 2CO 2 Therefore, For each Glucose molecule, the Krebs Cycle produces 6NADH, 2FADH 2, 4CO 2, and 2ATP Therefore, For each Glucose molecule, the Krebs Cycle produces 6NADH, 2FADH 2, 4CO 2, and 2ATP

Krebs Cycle ATP NETS: 3NADH, 1ATP, 1FADH 2, & 2CO 2

Electron Transport Chain Summary 34 ATP Produced 34 ATP Produced H 2 O Produced H 2 O Produced Occurs Across Inner Mitochondrial membrane Occurs Across Inner Mitochondrial membrane Uses coenzymes NAD+ and FAD+ to accept e- from glucose Uses coenzymes NAD+ and FAD+ to accept e- from glucose NADH = 3 ATP’s NADH = 3 ATP’s FADH 2 = 2 ATP’s FADH 2 = 2 ATP’s

Electron Transport Chain Animation Electron Transport Chain Animation

What happens if there isn’t enough oxygen for Respiration?

What do we use fermentation for?

Photosynthesis Light _________ Reactions ______ & NADPH H20H20 Light ________________ Reactions ATP & ________ Calvin Cycle Oxygen H20

Cellular Respiration Oxygen glycolysis No O2 O2 Fermentation Krebs Cycle Electron Transport Chain

How do photosynthesis and respiration go together?