Aerobic System

Question 1

What is Oxidative Metabolism?

Answer 1

Complete breakdown of carbohydrates (glycolysis), fats (beta-oxidation), to CO2 and H2O

Relies on oxygen to fuel for energy, yields much more ATP than anaerobic systems (35 ATP per unit of substrate)

Occurs in mitochondria

Central steps:
- Formation of acetyl CoA
- Oxidation of acetyl CoA in kreb cycle (able to reduce coenzymes)
- Formation of ATP (electron transport chain)- coenzymes are oxidized

End product of oxidative metabolism:
ATP, H2O,CO2

Question 2

Why does the amount of ATP generated from ‘slow’ (aerobic) glycolysis vs. ‘fast’ (anaerobic) glycolysis differ?

Answer 2

It can yield much more energy for slow glycolysis.

Anaerobic does incomplete oxidation of glucose 2 ATP per glucose, 3 ATP per glycogen

Aerobic: 39 ATP per molecule of glycogen

Glycolysis: in cytosol

Kreb cycle: mitochondria

Question 3

What is the fate of pyruvate in the presence of oxygen?

Answer 3

Enter mitochondria, acetyl CoA

Or converted to lactate without O2

Based on how much O2 is available

Acetyl CoA enter Krebs Cycle

Question 4

What are the basics of the mitochondria?

Answer 4

➢ Powerplants of the cell

➢ Responsible for the majority of ATP produced in the cell

Processes that occur in the mitochondria
➢ Beta oxidation (Matrix)
➢ Krebs Cycle (Matrix)
➢ Electron transport chain (Matrix and Inner membrane)

Question 5

Krebs Cycle

Answer 5

Fuels ETC

Cycle ‘begins’ with Acetyl CoA (the Krebs cycle ‘feeder’)

Acetyl-CoA + final product (oxaloacetate) = Citrate

Question 6

Why is NADH and FADH2 Important?

Answer 6

Electron Carriers: Transport high-energy electrons to the electron transport chain.

Energy Production: Help create a proton gradient for ATP synthesis via oxidative phosphorylation.

Regenerate NAD+ and FAD: Essential for continuous metabolic processes like glycolysis.

Metabolic Roles: Involved in fatty acid oxidation and the citric acid cycle.

Question 7

Understand the basics of ETC and ATP synthesis in Mitochondria

Answer 7

Reducing equivalents (NADH and FADH2) ‘donate’ electrons that are sent down an
electron ‘chain’ along the inner mitochondrial membrane

Electron transfer coupled with H+ pumped out into inner membrane space
O2 is the electron acceptor!

ATP Synthase uses H+ gradient to create energy for ATP synthesis