Which of the following statements is a plausible description of some aspect of protein secretion from prokaryotic cells?
a. Prokaryotes are unlikely to be able to secrete proteins because they lack an endomembrane system.
b. In prokaryotes, the ribosomes that are involved in the synthesis of secreted proteins are located outside of the cell.
c. Proteins that are secreted by prokaryotes may be synthesized on ribosomes that are associated with the cytoplasmic surface of the plasma membrane.
d. The mechanism of protein secretion in prokaryotes is probably the same as that in eukaryotes.