Biology 30 Structure & Function of Cells (Part 2) Bioenergetics: Energy: Potential energy: Examples: Kinetic energy Examples: Energy can be transformed: Thermodynamics: First law of Thermodynamics: Second law of Thermodynamics Cellular Metabolism: Includes: Two types of metabolic pathways: Anabolic pathway: Catabolic pathway: Biology 30 Lecture Structure & Function of Cells (Part 2) Page 1 of 5
Cells use & transform matter & energy: What is respiration? What is the main function of cellular respiration? Glucose provides energy for the cell (p. 70, Fig 3.23) RESPIRATION EQUATION: Reduction C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O + Energy (ATP) *Key = follow the H + s. Oxidation Oxidation: Reduction: Is cellular respiration a catabolic or anabolic reaction? Overview of Cellular Respiration (p. 70; Fig. 3.24): Aerobic respiration: 1) 2) 3) 4) AEROBIC RESPIRATION Glycolysis: (p. 71; Fig. 3.25) What biological molecular group is worked on during this process? What s the final product sugar end product? What is the net yield of energy produced from 1 glucose molecule? 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 Biology 30 Lecture Structure & Function of Cells (Part 2) Page 2 of 5
Results in: pyruvates 4 ATP 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: Preparatory step (p. 72, Fig 3.26) What biological molecular group is worked on during this process? What s the final product end product? What is the net yield of energy produced from 1 pyruvate molecule? 2 pyruvate (3C) 2 acetyl CoA (2C) 2 CO 2. 2 NAD + + H +. 2 NADH Citric Acid Cycler (Krebs Cycle): (p. 96-97; Fig. 6.9 A & B) Acetyl CoA + Oxaloacetate (OAA) citrate (2 C) (4 C) (6 C) citrate synthase What biological molecular group is worked on during this process? What s the final product sugar end product? What is the net yield of energy produced from 1 glucose acetyl CoA molecule? molecule? 2 acetyl CoA + 2 OAA 2 Citrate 2 FADH 2. 2 Turns Illustrated 2 FAD + 6 NAD + 2 ATP 6 NADH 2 ADP + 2 P i Why does it require 2 turns of the Citric Acid Cycle to completely oxidize 1 glucose molecule? (Hint: Think back to glycolysis) Products produced Cycle Net Yield: ATP Biology 30 Lecture Structure & Function of Cells (Part 2) Page 3 of 5
NADH FADH 2. CO 2. Electron Transport Chain & Oxidative Phosphorylation: (p 74, Fig 3.28) Proteins complexes & ATP synthase What is oxidative phosphorylation? Is ATP produced directly? Each NADH = ATP Each FADH 2 = ATP Final electron acceptor? Where does the O 2 come from? How does the O 2 get to the cells? Where does the water (metabolic water) come from? Energy yield from aerobic respiration: Glycolysis: Primer RXN: Krebs Cycle: 2 ATP 2 NADH 2 NADH 2 ATP 6 NADH 2 FADH 2. (p. 75, Fig. 3.29A) # of ATPs Total ATPs NOTE: Eukaryotes = 36 38 ATPs Do the numbers agree? Why or why not? What happens when cyanide & carbon monoxide accumulate in our bodies? Two fates of pyruvate depend on O 2 : Biology 30 Lecture Structure & Function of Cells (Part 2) Page 4 of 5
1) If O 2 is present: 2) If O 2 is not present: Anaerobic Respiration: (p. 3.31, Fig 3.31) a) Lactic Acid Fermentation 2 pyruvates 2 Lactic acid (lactate) Occurs when: Results in: Lactic acid build-up results in: 1) Cori cycle: 1) In skeletal muscles: 2) 2) In the liver: Two fates lactic acid: a) b) b) Alcohol Fermentation 2 pyruvates 2 ethanol (ethyl alcohol) Occurs when: Results in: What organisms undergo this type of metabolism? What is the connection between breathing and cellular respiration? Additional energy sources? Biosynthesis? Biology 30 Lecture Structure & Function of Cells (Part 2) Page 5 of 5