Presentation on theme: "Cellular Respiration Notes: 10/8/12. 8.1.3 Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs Matrix: –"— Presentation transcript:
Cellular Respiration Notes: 10/8/12
8.1.3 Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs Matrix: – Watery substance that contains ribosomes and many enzymes. – These enzymes are vital for the link reaction and the Krebs cycle. Inner membrane: – The electron transport chain and ATP synthase are found in this membrane. – These are vital for oxidative phosphorylation.
8.1.3 Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs Space between inner and outer membranes: – Small volume into which protons are pumped into. – Small volume high concentration gradient can be reached very quickly. – This is vital for chemiosmosis. Outer membrane: – Separates the contents of the mitochondrion from the rest of the cell. – Creates a good environment for cell respiration.
8.1.3 Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs Cristae: – Tubular projections of the inner membrane – Increase the surface area for oxidative phosphorylation. Mitochondrial DNA – Encode mitochondrial enzymes. Ribosomes – Translation of mitochondrial proteins.
8.1.6 Explain the relationship between the structure of the mitochondrion and its function A. Matrix site for Krebs' cycle link reaction ATP synthesis B. Inner Membrane site of oxidative phosphorylation e– transport chain increase surface area ATP synthesis; C. Inner Membrane Space H+ / proton build up; C A B
C Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs A: Matrix B: Inner membrane C: Intermembrane space C A B
8.1.2 Outline the process of glycolysis, including phosphorylation, lysis, oxidation and ATP formation. Occurs in ________________ Is not ___________ dependent Glucose is Phosphorylated (-__ ATP) Lysis: phosphorylated 6-carbon sugar is broken down into __ ____________ – Glucose is ___________ ___________ phosphorylation produces 2 ATP NET synthesis of ___ ATP and ___ NADH
Glycolysis Overview Major phases – Energy investment – Lysis – Energy harvesting
Summary of glycolysis: – Each molecule of glucose is broken down to two molecules of pyruvate – A net of two ATP molecules and two NADH (high- energy electron carriers) are formed
Energy Investment Phase – Glucose is phosphorylated twice – Requires the INVESTMENT of two ATP molecules
Lysis – The phosphorylated glucose is broken into two triose-phosphate molecules (called G3P)
Energy harvesting phase – In a series of reactions, each molecule is converted into a pyruvate, generating two ATPs per conversion, for a total of four ATPs
Energy harvesting phase – each G3P has an inorganic phosphate group added (P i ). – Simultaneously, NAD+ gains H and 2e- to become NADH PiPi PiPi PiPi NAD + Removes H + and 2 e - to become NADH G3P PiPi
8.1.2 Outline the process of glycolysis, including phosphorylation, lysis, oxidation and ATP formation. Step 1 - Glucose is phosphorylated. Step 2 - Lysis of hexose (6C) biphosphate into two triose (3C) phosphates Step 3 - Each triose (3C) phosphate molecule is oxidized. Step 4 – Two pyruvate molecules (3C) are formed by removing two phosphate groups from each molecule. Type of phosphorylation?
Fermentation enables some cells to produce ATP without the use of oxygen Cellular respiration – Relies on oxygen to produce ATP In the absence of oxygen – Cells can still produce ATP through fermentation
From glycolysis Fermentation (anaerobic) Does not produce more ATP, but is necessary to regenerate NAD+, which must be available for glycolysis to continue Human muscles cells Bacteria Yeast
Fermentation consists of – Glycolysis plus reactions that regenerate NAD +, which can be reused by glycolysis In alcohol fermentation – Pyruvate is converted to ethanol in two steps, one of which releases CO 2 During lactic acid fermentation – Pyruvate is reduced directly to NADH to form lactate as a waste product
8.1.4 Explain aerobic respiration, including the link reaction, the Krebs cycle, the role of NADH + H +, the electron transport chain and the role of oxygen
Link Reaction Pyruvate (C3) + NAD+ + CoA Acetyl-CoA (2C) + NADH + CO 2 Per Glucose NET: 2 NADH + 2 CO Acetyl-CoA
Krebs Cycle Acetyl-CoA (2C) + Oxaloacetate (4C) Citrate (6C) + CoA Citrate (6C) + 3 NAD+ + FAD+ + ADP Oxaloacetate (4C) + 2 CO NADH + FADH ATP Per Glucose NET: 4 CO NADH + 2 FADH ATP
FAD+ accepts electrons from other molecules to form FADH2 which can then donate electrons to the ETC
Carbohydrates, proteins, and lipids can be used as energy sources; metabolites involved in energy production can be used to synthesize carbohydrates, proteins, lipids, nucleic acids, and cellular structures.