What creates ATP molecules, but then gains overall only two

Glycolysis creates ATP molecules, but then gains overall only two.

Explanation:

Glycolysis refers to the breakdown of glucose molecules into ATP. It occurs in the process of respiration.

Respiration is a process in which energy is released due to the breakdown of glucose molecules with the addition of oxygen or without oxygen forming carbondioxode, water and energy in the form of Adenine tri phosphate (ATP). There are two types of respiration i. e. aerobic and anaerobic respiration. In aerobic respiration oxygen is used which produces 38 ATP molecules while in anaerobic respiration, only 2 ATP molecules are produced.