Explain the formation of $PEP$ (Phosphoenolpyruvate) during glycolysis.

(N/A) The formation of $PEP$ occurs during the final stages of glycolysis.
$1$. $2$-phosphoglycerate ($2$-$PGA$) is converted into phosphoenolpyruvate $(PEP)$ by the enzyme enolase.
$2$. This reaction involves the removal of a water molecule $(H_2O)$,which is a dehydration reaction.
$3$. Subsequently,$PEP$ is converted into pyruvic acid by the enzyme pyruvate kinase,a step that generates $ATP$ through substrate-level phosphorylation.
$4$. Pyruvic acid is the key product of glycolysis. Its metabolic fate depends on cellular requirements,leading to three major pathways: $(i)$ Lactic acid fermentation,$(ii)$ Alcoholic fermentation,or $(iii)$ Aerobic respiration.