Cellular Respiration: Energy Transfer

NGSS HS-LS1-7: Use a model to illustrate that cellular respiration is a chemical process whereby the bonds of food molecules and oxygen molecules are broken and the bonds in new compounds are formed resulting in a net transfer of energy.

Net Energy Transfer
0 ATP
Mitochondrion Model

Chemical Process Overview

1 C6H12O6 Glucose (Food)
+
6 O2 Oxygen
Recombination
6 CO2 Carbon Dioxide
+
6 H2O Water
+
Energy ATP + Heat

Conservation of Matter

Notice that the exact same number of atoms exist before and after the reaction. The atoms are simply rearranged into new compounds.

6
Carbon
12
Hydrogen
18
Oxygen

Energy Transfer & Pathways

Aerobic Respiration: When Oxygen is present, 1 Glucose molecule combines with 6 Oxygen molecules to produce ~36 ATP, Carbon Dioxide, and Water.

Anaerobic Respiration: If Oxygen is depleted, cells use anaerobic pathways (like fermentation), which produces only ~2 ATP and Lactic Acid. Try lowering the Oxygen slider to see this effect!