Redox Reactions oxidation: involves loss of electrons, often occur with loss of hydrogen, occur with gain of oxygen reduction: involves gain of electrons, often occur with loss of oxygen, occur with gain of hydrogen redox reactions: coupled reactions that play a key role in flow of energy, involve gain/loss of electrons
Energy Terms anabolic: using energy to build large molecules catabolic: breaking down compounds into smaller molecules to release energy metabolism: all the chemical reactions that take place in cells endergonic: reaction that requires input of energy exergonic: reaction that releases energy
ATP: adenosine triphosphate substrate-level phosphorylation: process of forming ATP by the physical addition of a phosphate group to ADP
ATP cycle: Process of breaking down glucose and creating energy, ADP + Pi -->ATP
Diagram of Mitochondria & Parts
Cellular Respiration – 4 Stages (Aerobic)
Glycolysis: Anaerobic process that occurs in the cytosol/cytoplasm. It breaks down glucose into two 3-carbon pyruvate molecules. Key terms: glucose, glyceraldehyde 3-phosphate (G3P)
Activation: Substrate-level phosphorylation adds 2 phosphate groups to glucose. Uses 2 ATP molecules and produces fructose 1,6 – biphosphate.
Lysis: The 6-carbon molecule (glucose) turns into G3P and DHAP (the dhap is converted to G3P). Basically split into two 3-carbon molecules of G3P (glyceraldehyde-3-phosphate).
Oxidation: G3P is oxidized by NAD+ which is reduced to NADH. This releases energy to attach phosphates to sugar molecules producing 1,2-biphosphoglycerate. This happens twice – once for each G3P.
Phosphates are transferred to ADP producing 4 molecules of ATP. This is a net gain of 2 ATP and 2 pyruvate.
NADH molecules go to the ETC
If oxygen is present, pyruvate will enter the Krebs cycle
Pyruvate oxidation: Aerobic process that occurs in mitochondrial matrix. Pyruvate molecules are transported to the mitochondria through transport protein.