Biology Prokaryotes

Prokaryotes

• Prokaryotes are the smallest organisms in size, but they’re grand in almost every other way. Their forms are ancient, represented in fossils going back to the first life on Earth. If we count individuals, there are far more prokaryotes today than all other organisms combined.

• Prokaryotes can be found in every imaginable habitat, including some so extreme that no other forms of life could survive there.

• In this Lesson, we’ll survey the diversity of prokaryotic organisms. Their external shapes may be simple, but their lifestyles and biochemistry are very complex.

• Although some prokaryotes are well-known causes of disease, many others are beneficial, and neither humans nor any other species could survive without them.