Cellular Energy

aerobic cellular respiration

glycolysis → pyruvate decarboxylation → Krebs cycle → oxidative phosphorylation

glycolysis takes place…

in cytosol

glycolysis equation

glucose → 2 ATP + 2NADH + 2 pyruvate

first enzyme used in glycolysis

hexokinase

what does hexokinase do

uses 1 ATP to turn glucose into glucose-6-phosphate

2nd enzyme of glycolysis

isomerase

what does isomerase do

turns glucose-6-phosphate into fructose-6-phosphate

3rd enzyme of glycolysis

phosphofructokinase

what does phosphofructokinase do

uses ATP to phosphorylate fructose-6-phosphate into fructose-1,6-biphosphate

fructose-1,6-biphosphate splits into…

2 G3P molecules

pyruvate decarboxylation equation

CO₂ + NADH + acetyl-CoA

where does pyruvate decarboxylation occur

mitochondrial matrix

Krebs cycle equation

acetyl-CoA → 2 CO₂ + 3 NADH + FADH₂ + ATP

where does krebs cycle occur

mitochondrial matrix

what is regenerated during krebs cycle

oxaloacetate

oxidative phosphorylation equation

NADH + FADH₂ + O₂ → ATP + H₂O

where does oxidative phosphorylation occur

mitochondrial membrane

final electron acceptor for krebs cycle

O₂ (forms water byproduct)

lactic acid regenerates…

NAD⁺ (via conversion of pyruvate to lactate)

alcohol fermentation regenerates…

NAD⁺ (via decarboxylation of pyruvate to acetaldehyde)

photosynthesis equation

6CO₂ + 6 H₂O → C₆H₁₂O₆ + 6O₂