ETC occurs here Krebs Cycle Occurs here Cellular

ETC occurs here Krebs Cycle Occurs here

Cellular Respiration: • A series of BIOCHEMICAL PATHWAYS… the product of 1 reaction is the reactant of the next reaction • Occurs in the mitochondria ( & cytoplasm) • Is the process of creating ENERGY…ATP!!!! • food broken down into organic molecules, ultimately broken down into GLUCOSE – glucose changed into/converted into ATP (ENERGY) • enzyme controlled

CR • • Occurs in BOTH PLANTS AND ANIMALS Has 3 stages: 1. Glycolysis – anaerobic: w/o Oxygen 2. Krebs Cycle (aka: Citric acid cycle) – aerobic: require oxygen 3. Electron Transport Chain (ETC) aerobic

Glycolysis: • Occurs in the cytoplasm (cytosol) • Chemical RXN where sugar. GLUCOSE is broken down into 2 Pyruvic Acid molecules • Produces 2 ATP molecules for every 1 glucose molecule • NAD provides energy for the change (an e- energy carrier)

Products from Glycolysis move into the Mitochondria THE PRODUCT (Pyruvic Acid) WILL THEN BE USED AS THE REACTANT IN THE NEXT REACTION Hence…Biochemical Pathway

CK ? ? Topic CR Date: 10 -11 -10 1. What is the purpose of Cellular Respiration? 2. Where are the 2 places does CR occurs? 3. What are the 3 stages of CR?

CK ? ? Topic CR Date: 10 -11 -10 4. How many usable ATP result from Glycolysis? 5. What is the second stage of CR? 6. Where does the second stage take place? 7. What does the term aerobic mean?

Stage 2 Krebs (Citric Acid Cycle): • Oxygen is required – Aerobic Respiration • A series of chemical rxns… a cycle – Pyruvic Acid is further broken down: • into Acetyl Co. A • CO 2 is produced and • released into the air from animal cells • Or in plants move to the chloroplasts to be used for photosynthesis

Pyruvic Acid is further broken down: • 2 ATP are produced and • NADH & FADH are produced (high energy electron carriers) which will provide the energy to bond the last phosphate in ADP to create ATP! ENERGY

Citric Acid Cycle: • Takes place in the matrix of the mitochondria

In summary: Pyruvic Acid is further broken down into Acetyl Co. A as it enters the Krebs Cycle

Stage 3 Electron Transport Chain:

Stage 3 Electron Transport Chain: • Occurs in the inner Mitochondrial Membrane • Majority of the ATP (34 ATP) are produced during ETC • The high-energy electrons produced during the Krebs Cycle (NADH and FADH 2) are used to convert ADP into ATP

Chemical Formula Cellular Respiration: Sugar + Oxygen Energy + Carbon Dioxide + Water C 6 H 12 O 6 + 6 O 2 36 ATP + 6 CO 2 + 6 H 2 O

Glycolysis: • Goal: To break down sugar into 2 Pyruvic Acids • Who: Both plant and animals • Where: In the cytoplasm of the cell • Products: 2 ATP, 2 NADH, 2 Pyruvic

Krebs cycle: • Goal: convert (change) the pyruvic acid into NADH and FADH 2 • Where: mitochondria • Products: Energy carriers: NADH & FADH 2, CO 2 (released to environment) and 2 ATP

Electron Transport Chain (chemiosmosis making ATP!!) • Goal: break down NADH and FADH 2 to produce ATP • Where: Mitochondria membrane • Products: 32 -34 ATP

AS A RESULT OF AEROBIC CELLULAR RESPIRATION: • • 2 ATP FROM GLYCOLYSIS 2 ATP FROM KREBS CYCLE 32 -34 ATP FROM THE ETC TOTAL OF: – 36 -38 ATP FOR EVERY MOLECULE OF GLUCOSE

IF NO OXYGEN IS AVAILABLE… • Anaerobic Respiration (FERMENTATION): – Begins with Glycolysis – DOES NOT REQUIRE OXYGEN • Also known as FERMENTATION

2 types of FERMENTATION 1. Alcoholic fermentation 2. Lactic acid fermentation

Lactic Acid Fermentation: • Pyruvic acid converted (changed) into lactic acid • Used to make cheese, yogurt, and is the stuff that accumulates in muscles (sore) • 2 ATP only

Alcoholic Fermentation: • Used to make beer, wine • Yeast used in process • 2 ATP only

Reproduce Through BUDDING!!

Clearly Not as efficient as aerobic respiration

• Photosynthesis and cellular respiration are opposite rxns.

Photosynthesis & CR are opposite rxns. Photosynthesis : • removes Carbon Dioxide from the atmosphere and puts back oxygen. Cellular Respiration: • Removes oxygen from the atmosphere and puts back carbon dioxide.