Plasma membrane of prokaryotic cells

A 75 Å thick unit-type membrane surrounding the cytoplasm is treated.

It has a similar structure to the membrane of eukaryotic cells , although it does not contain sterols. Another peculiarity is the existence of mesosomes, internal folds of the plasma membrane.

In addition to having the same functions as the eukaryotic plasma membrane, such as limiting the cell and regulating the passage of nutritional substances, mesosomes have other functions:

• They hold the bacterial chromosome.
• They contain enzymes that:
  • They direct the duplication of bacterial DNA by DNA polymerase.
  • They carry out cellular respiration, performing a function similar to that of mitochondria (they lack them).
  • They carry out photosynthesis, in photosynthetic bacteria.
  • They perform chemosynthesis, in chemosynthetic bacteria.