Glycolysis Overview and Processes

What is the primary role of glycolysis in cellular metabolism?

Which molecule is produced at the end of glycolysis?

Glycolysis does not require oxygen. What type of process is this characterized as?

What is the starting substrate for glycolysis?

Which enzyme catalyzes the final step of glycolysis, producing pyruvate?

During glycolysis, how many molecules of ATP are produced as outputs?

What role does NADPH play in the phosphorylation step of glycolysis?

What happens to pyruvate under anaerobic conditions after glycolysis?

Glycolysis is the breakdown of ______, which is a 6-carbon molecule.

The end product of glycolysis is two molecules of ______.

Glycolysis occurs in the ______ of the cell.

Oxidative phosphorylation involves the transfer of a phosphate group to ______.

The enzyme used in the first step of glycolysis is called ______.

In the absence of oxygen, pyruvate is converted into ______.

The metabolic pathway that converts glucose into energy is known as ______.

Two molecules of ______ are produced as outputs of glycolysis.

Glycolysis Overview

Glycolysis is the breakdown of glucose (a 6-carbon molecule) into two molecules of pyruvate (a 3-carbon molecule).
It's a metabolic pathway converting glucose to energy and intermediates for other metabolic pathways.
It's an anaerobic process, meaning it doesn't require oxygen, but the presence or absence of oxygen affects the fate of pyruvate.
It's the first step in cellular respiration, preceding the Krebs Cycle and the Electron Transport Chain (ETC).
Glycolysis occurs in the cytoplasm of the cell.
With oxygen, pyruvate enters the Krebs Cycle; without oxygen, it's converted to lactate.

Inputs and Outputs

Inputs: One glucose molecule, 2 ATP molecules, and 2 NAD+ molecules.
Outputs: Two pyruvate molecules, 2 ADP molecules, and 2 NADH molecules.

Glycolysis Steps

Phosphorylation (Hexokinase): A dehydrogenase enzyme is used to oxidize and phosphorylate Glyceraldehyde-3-Phosphate, forming 1,3-Bisphosphoglyceric acid. The phosphate comes from NAD+.
Oxidative Phosphorylation: A phosphate group from 1,3-Bisphosphoglyceric acid is transferred to ADP, forming ATP and 3-Phosphoglyceric acid. This reaction is catalyzed by phosphoglycerate kinase. The source of the inorganic phosphate in this step is not NADPH, but is a result of a high-energy phosphate bond being transferred.
Transfer of Phosphate Group (Phosphoglycerate Mutase): The phosphate group is moved to the second carbon atom, producing 2-Phosphoglyceric acid, catalyzed by phosphoglycerate mutase.
Dehydration (Enolase): 2-Phosphoglyceric acid loses a water molecule to produce Phosphoenolpyruvate. The enzyme responsible is enolase.
Transfer of Phosphate Group (Pyruvate Kinase): A final ATP molecule is produced when a phosphate group from Phosphoenolpyruvate is transferred to ADP, creating pyruvate. The enzyme catalyzing this step is pyruvate kinase.

This quiz explores the glycolysis metabolic pathway, detailing the breakdown of glucose into pyruvate and its significance in cellular respiration. Discover the inputs and outputs of glycolysis, as well as the sequential steps involved in this critical energy conversion process. Test your understanding of this fundamental biological pathway.