Glycolysis: Cellular Respiration Process

Glycolysis

• Definition: Glycolysis is the first step in cellular respiration, where one glucose molecule (6-carbon sugar) is converted into two pyruvate molecules (3-carbon sugars) in the cytosol.
• Energy yield: 2 ATP and 2 NADH molecules are produced during glycolysis.
• Steps:
  1. Glucose phosphorylation to glucose-6-phosphate (G6P)
  2. Conversion of G6P to fructose-6-phosphate (F6P)
  3. Conversion of F6P to fructose-1,6-bisphosphate (F1,6BP)
  4. Cleavage of F1,6BP to glyceraldehyde-3-phosphate (G3P) and dihydroxyacetone phosphate (DHAP)
  5. Conversion of DHAP to G3P
  6. Conversion of G3P to 1,3-bisphosphoglycerate (1,3BPG)
  7. Conversion of 1,3BPG to 3-phosphoglycerate (3PG)
  8. Conversion of 3PG to pyruvate

NADH2

• Definition: NADH2 (Nicotinamide adenine dinucleotide) is a coenzyme that plays a crucial role in energy metabolism.
• Function: NADH2 acts as an electron carrier, transferring electrons from one reaction to another.
• Reduction of NAD+: During glycolysis, NAD+ is reduced to NADH2, resulting in the formation of 2 NADH2 molecules.
• Energy yield: Each NADH2 molecule can produce 2.5 ATP during oxidative phosphorylation in the electron transport chain.
• Importance: NADH2 is a key player in the electron transport chain, generating ATP during cellular respiration.

Glycolysis

• Glycolysis is the first step in cellular respiration, converting one glucose molecule (6-carbon sugar) into two pyruvate molecules (3-carbon sugars) in the cytosol.
• Energy yield of glycolysis is 2 ATP and 2 NADH molecules.
• Glucose phosphorylation to glucose-6-phosphate (G6P) is the first step of glycolysis.
• Fructose-6-phosphate (F6P) is produced from glucose-6-phosphate (G6P) in the second step of glycolysis.
• Fructose-1,6-bisphosphate (F1,6BP) is formed from fructose-6-phosphate (F6P) in the third step of glycolysis.
• Glyceraldehyde-3-phosphate (G3P) and dihydroxyacetone phosphate (DHAP) are produced from fructose-1,6-bisphosphate (F1,6BP) in the fourth step of glycolysis.
• Dihydroxyacetone phosphate (DHAP) is converted to glyceraldehyde-3-phosphate (G3P) in the fifth step of glycolysis.
• Glyceraldehyde-3-phosphate (G3P) is converted to 1,3-bisphosphoglycerate (1,3BPG) in the sixth step of glycolysis.
• 1,3-bisphosphoglycerate (1,3BPG) is converted to 3-phosphoglycerate (3PG) in the seventh step of glycolysis.
• 3-phosphoglycerate (3PG) is converted to pyruvate in the eighth and final step of glycolysis.

NADH2

• NADH2 (Nicotinamide adenine dinucleotide) is a coenzyme that plays a crucial role in energy metabolism.
• NADH2 acts as an electron carrier, transferring electrons from one reaction to another.
• NAD+ is reduced to NADH2 during glycolysis, resulting in the formation of 2 NADH2 molecules.
• Each NADH2 molecule can produce 2.5 ATP during oxidative phosphorylation in the electron transport chain.
• NADH2 is a key player in the electron transport chain, generating ATP during cellular respiration.

Learn about glycolysis, the first step in cellular respiration, where glucose is converted into pyruvate, producing ATP and NADH. Understand the steps involved in this process.