Keystone Biology Practice Exam

Prokaryotic cells, which include bacteria and archaea, are characterized by their simplicity and lack of membrane-bound organelles. One of the key features of prokaryotic cells is that they do not have mitochondria, which are organelles found in eukaryotic cells responsible for respiration and energy production.

In prokaryotes, cellular respiration occurs in the cell membrane rather than in specialized organelles like mitochondria. As for the other components, prokaryotic cells do possess a cell membrane, ribosomes, and chromosomes. The cell membrane controls the passage of substances in and out of the cell, ribosomes are essential for protein synthesis, and chromosomes, usually in the form of a single circular DNA molecule, contain the genetic material necessary for the cell's functions and reproduction. This distinction highlights a fundamental difference between prokaryotic and eukaryotic cells.