Glycolysis begins with one glucose molecule and ends with two molecules of:

1. Glucose is a six-carbon ring-shaped sugar. 2. Glycolysis splits that ring evenly in two. 3. Glycolysis begins with the six carbon ring-shaped structure of a single glucose molecule and ends with two molecules of a three-carbon keto acid called pyruvate. 4. Lactate and ethanol appear only later, in fermentation. _Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 7 'Cellular Respiration', sections 7.1-7.7_