You have learned about the organelles that are important to your own cells. It may surprise you to find out that many living cells can survive on far fewer structures than what your cells have. In this lesson, you'll learn about cells that survive--and thrive--without a nucleus and without any membrane-bound organelles. These organisms are called prokaryotes. Like eukaryote, the word prokaryote was created using Greek roots: pro means "before" and karyon means "kernel," or center. Scientists call these more primitive cells prokaryotes because they existed long before there were eukaryotes, cells containing a nucleus.
Organisms containing prokaryotic cells aren't just prehistoric oddities, though they appeared on earth long before eukaryotes. Prokaryotes are essential to the survival of eukaryotes and to the function of any ecosystem. As you watch the video below, think about the prokaryotes that are part of your everyday life.
You are interacting with prokaryotes throughout the day. When? In your intestines there are bacteria that break down food. In your mouth there is bacteria that causes tooth decay. In the human body there are 10 times as many bacterial cells as human cells. Bacteria called Alcanivorax can remove oil from water after an oil spill. Bacteria can break down plastic debris and reduce acid rain runoff. Prokaryotes are all around you. Can you think of a way a prokaryote has helped you today?
Question
How could the absence of a nucleus be a disadvantage for a cell?
