Where does this occur?

• Occurs in the mitochondria of cells

• Mitochondria are nicknamed the "powerhouses" of the cell because cellular respiration provides energy to the cell

Overview

• Breaks down glucose into usable energy (ATP) for the cell

• Uses oxygen

• Produces carbon dioxide and water as byproducts

• ATP stands for Adenosine Triphosphate

The Stages of Cellular Respiration

• Glycolysis - breaks glucose into pyruvate molecules, occurs in the cytoplasm

• Krebs Cycle - breaks down pyruvate, occurs in matrix of mitochondria

• Electron Transport Chain - uses electrons to produce majority of ATP, occurs on inner membrane of mitochondria

Glycolysis

• Splits 1 glucose molecule into 2 pyruvate molecules

• Produces 2 ATP molecules per glucose molecule

Krebs Cycle

• Pyruvate enters mitochondria and is broken down into acetyl CoA

• Acetyl CoA enters Krebs cycle and is further broken down into CO2

• Produces 2 ATP, electrons, and hydrogen atoms per acetyl CoA molecule

Electron Transport Chain

• Electrons passed along series of proteins in inner membrane

• Oxygen serves as final electron acceptor

• Movement of electrons releases energy used to pump H+ ions creating gradient

• Flow of H+ ions powers ATP synthase to make ATP

Results of Cellular Respiration

• Yields 36-38 ATP molecules per glucose molecule

• Produces CO2 and H2O as waste products

Connection to Photosynthesis

• Photosynthesis produces glucose and oxygen

• Cellular respiration breaks down glucose, uses oxygen, and produces CO2 and H2O

• The two processes complement each other in the carbon cycle

Summary

• Glycolysis - breaks glucose into pyruvate molecules, occurs in the cytoplasm

• Krebs Cycle - breaks down pyruvate, occurs in matrix of mitochondria

• Electron Transport Chain - uses electrons to produce majority of ATP, occurs on inner membrane of mitochondria