Biology 20 Lecture Cellular Respiration (0210) 1 Biology 20 Cellular Respiration What is respiration? (p. 90, fig 6.2) What is the main function of cellular respiration? (p. 90, fig 6.2) RESPIRATION EQUATION: (p. 91, fig 6.3) Reduction C6H12O6 + 6 O2  6 CO2 + 6 H2O + Energy (ATP) Oxidation Reference: p. 92; Fig. 6.5  *Key = follow the H+s. Oxidation: Reduction: Is cellular respiration a catabolic or anabolic reaction? Overview of Cellular Respiration (p. 93; Fig. 6.9): Aerobic respiration: 1) 2)) 3) Anaerobic respiration: 1) 2) a) b) Glycolysis: (p. 94; Fig. 6.7A-C) Refers to: Occurs: Energy investment phase: Steps 1 – 4 C-C-C-C-C-C 2 ATP  How many ATP's required (used)? Results in 2 molecules of 3 phosphoglyceraldehyde (G3P) C-C-C C-C-C Note: Step 5 is an isomeration step between G3P & Dihydixyacetone phosphate Energy yielding phase: Steps 6 – 10 (G3P) C-C-C C-C-C Results in: pyruvates 4 ATP Biology 20 Lecture Cellular Respiration (0210) 2 ATP produced 2 NADH  NADH produced (PYR) C-C-C C-C-C (PYR) Nicotinamide adenine dinucleotide (NADH) – energy rich molecule which will be shuttled to the ETC & undergo oxidative phosphorylation to yield more (Think: Disney dollars - can only get this energy converted to ATP at the ETC) Glycolysis Net Yield: pyruvates: ATP: NADH: What is Substrate-level phosphorylation? (p. 94, Fig. 6.7B) Two fates of pyruvate depend on O2: 1) If O2 is present: 2) If O2 is not present: Aerobic Respiration: Glycolysis  Citric Acid Cycle (Kreb’s Cycle): Occurs: Grooming phase: (p. 96; Fig. 6.8) Occurs where: 2 pyruvate (3C) 2 acetyl CoA (2C) 2 CO2. 2 NAD+ + H+. 2 NADH Krebs Cycle: (p. 96 - 97; Fig. 6.9 A & B) Occurs: Acetyl CoA + Oxaloacetate (OAA) citrate (2 C) (4 C) (6 C) 2 acetyl CoA citrate synthaseBiology 20 Lecture Cellular Respiration (0210) 3 + 2 OAA 2 Citrate 2 FADH2. 2 Turns Illustrated 2 FAD+ 6 NAD+ 2 ATP 6 NADH 2 ADP + 2 Pi Why does it require 2 turns of the Krebs Cycle to completely oxidize 1 glucose molecule? (Hint: Think back to glycolysis) Krebs Cycle Net Yield: ATP NADH FADH2. CO2. Electron Transport Chain & Oxidative Phosphorylation: (p. 98; Fig. 6.10) Location: Proteins complexes & ATP synthase What is chemiosmosis? What is oxidative phosphorylation? Is ATP produced directly? Each NADH = ATP Each FADH2 = ATP Final electron acceptor? Where does the O2 come from? How does the O2 get to the cells? Where does the water (metabolic water) come from?Biology 20 Lecture Cellular Respiration (0210) 4 What happens when cyanide & carbon monoxide accumulate in our bodies? (p. 99, Fig. 6.11) Energy yield from aerobic respiration: (p. 100, Fig. 6.12) # of ATPs Glycolysis: 2 ATP 2 NADH Primer RXN: 2 NADH Krebs Cycle: 2 ATP 6 NADH 2 FADH2. Total ATPs NOTE: Eukaryotes = 36 – 38 ATPs Do the numbers agree? Why or why not? Fermentation:Biology 20 Lecture Cellular Respiration (0210) 5 a) Lactic Acid Fermentation (Fig. 6.15b) 2 pyruvates  2 Lactic acid (lactate) Occurs when: Location: Results in: Lactic acid build-up results in: 1) 2) Cori cycle: 1) In skeletal muscles: 2) In the liver: Two fates lactic acid: a) b) b) Alcohol Fermentation (Fig. 6.15 A) 2 pyruvates  2 ethanol (ethyl alcohol) Occurs when: Location: Results in: What organisms undergo this type of metabolism? What is the connection between breathing and cellular respiration? (p. 90; Fig. 6.2) LIPID METABOLISM: (p. 102; Fig. 6.15) Lipolysis:Biology 20 Lecture Cellular Respiration (0210) 6 Ketone bodies: As a result of: ketosis: results in: causes: ketoacidosis: AMINO ACID METABOLISM: (p. 102; Fig. 6.15) Are all the foodstuff that we eat converted into energy (ATP)? (p. 103; Fig. 6.16) Where does the fuel for respiration ultimately come