Why do bacteria perform the emden-Meyerhof pathway, need the pentose- phosphate pathway?

Why do bacteria perform the emden-Meyerhof pathway, need the pentose- phosphate pathway?

A-

photophosphorylation can be cyclical to produce additional ATP molecules. Why can’t oxidative phosphorylation be cyclical?

B-

How can you determine that a bacterium performs the pentose- phosphate cycle?