What is a mesosome in a prokaryotic cell? Mention the functions that it performs.

A mesosome is an infolding or invagination of the plasma membrane in certain prokaryotic cells observed under electron microscopy that appear as vesicular, tubular or lamellar extensions of the membrane

Functions attributed to mesosomes

• Increase membrane surface area to localize respiratory enzyme complexes, facilitating aerobic respiration analogous to mitochondrial cristae

• Serve as sites for cell wall (septum) formation during cell division, organizing synthesis machinery at the division plane

• Participate in DNA replication by anchoring the bacterial chromosome and coordinating replisome activity

• Aid in the distribution and segregation of replicated DNA to daughter cells, ensuring equal chromosome allocation

Modern consensus holds that mesosomes are largely artifacts produced by chemical fixation techniques rather than true cellular organelles in living bacteria