Respiration Chapter 9

Figure 6.4 Breathing Lungs Muscle cells Cellular respiration

Cellular Respiration The exact opposite of photosynthesis. The process by which living organisms get energy by breaking down carbohydrates. This important job is the responsibility of the mitochondria.

Ruby Lu’s cells are doing respiration ALL the time, even when she is sleeping! The bears are not living, so no respiration!

Ruby & Bella playing means more energy is needed, so more cellular respiration!

Glucose Glycolysis Cytoplasm Pyruvic acid Electrons carried in NADH Krebs Cycle Electrons carried in NADH and FADH 2 Electron Transport Chain Mitochondrion Figure 9–2 Cellular Respiration: An Overview Mitochondrion

A common fuel molecule for cellular respiration is glucose This is the overall equation for what happens to glucose during cellular respiration The Overall Equation for Cellular Respiration Unnumbered Figure 6.1 Glucose Oxygen Carbon dioxide WaterEnergy

Cellular Respiration Three Stages 1. Glycolysis 2. Citric acid cycle (Kreb’s Cycle) 3. Electron transport chain

Glycolysis Glycolysis is an anaerobic reaction Glucose is broken in half producing 2 pyruvic acid These molecules release 4 ATP’s. Unfortunately, glycolysis requires 2 ATP’s to get started so it is not very efficient.

Glucose To the electron transport chain Figure 9–3 Glycolysis Section Pyruvic acid

Glucose To the electron transport chain Figure 9–3 Glycolysis Section Pyruvic acid

Glucose To the electron transport chain Figure 9–3 Glycolysis Pyruvic acid

Oxygen Respiration can occur with or without oxygen. When there is no oxygen, you have two entirely different sets of reactions dependent on what type of organism you are.

Alcoholic Fermentation Occurs in yeast cells and some other organisms. Occurs when there is no oxygen. This is what causes bread to rise when being baked. This is also how we get wine and beer.

Lactic Acid Fermentation Occurs in animal cells Occurs when there is little or no oxygen What causes the burning sensation in muscles. Used in dairy industry to make cheese & yogurt

Citric Acid Cycle Also called the Krebs cycle- a series of aerobic chemical reactions

Electron transport chain The 3 rd and final stage. This chain releases 34 ATP’s and H 2 O as long as Oxygen is present. Very efficient!

Energy Production Comparisons

19 Eukaryotes (Have Membranes) Total ATP Yield 02 ATP - glycolysis (substrate-level phosphorylation) 04 ATP - converted from 2 NADH - glycolysis 06 ATP - converted from 2 NADH - grooming phase 02 ATP - Krebs cycle (substrate-level phosphorylation) 18 ATP - converted from 6 NADH - Krebs cycle 04 ATP - converted from 2 FADH 2 - Krebs cycle 36 ATP - TOTAL

Photosynthesis vs Cellular Respiration

Bill Nye and Respiration