Comparing and Contrasting the Prokaryotic and Eukaryotic Cells

My AP Biology Thoughts Unit 2 Cell Structure and Function

Welcome to My AP Biology Thoughts podcast, my name is Chloe and I am your host for episode #49 called Unit 2 Cell Structure and Function: Comparing and Contrasting the Prokaryotic and Eukaryotic Cells. Today we will be discussing the comparison between the functions and structures of these two cell types.

Segment 1: Introduction to Prokaryotes and Eukaryotes

• The main difference between prokaryotic and eukaryotic cells is the presence of the nucleus and other internal membranes. This lack of membrane in prokaryotic cells often causes them to lack crucial organelles which are present in Eukaryotic cells.
• In Eukaryotic cells, the genetic information, the DNA, is held within the nucleus.
• In a prokaryotic cell, the genetic material is carried on a singular piece of DNA which is attached to the cell membrane, and there is no enclosing membrane which causes the genetic information to come into direct contact with the cytoplasm. (This whole system is called a nucleoid, a concentration of DNA)
• Overall, the main difference is the presence of membrane bound organelles in eukaryotic cells, and absolutely no membrane bound organelles or a nucleus at all in prokaryotic cells.

Segment 2: More About Prokaryotes and Eukaryotes

Going more in depth, prokaryotes are ultimately unicellular organisms. In contrast, eukaryotic organisms can be unicellular, but eukaryotes are the building blocks of larger organisms

• Two examples of prokaryotes include bacteria and archaea. Eukaryotic cells make up everything besides these two organisms including fungi, plants, and animals.
• Specific similarities between the organelles present in both prokaryotic and eukaryotic cells is that they both contain a plasma membrane, ribosomes, cytoplasm, and DNA. Although they carry genetic information differently, it is important to remember that they both still possess it.
• It's important to understand the origin of these two different cells, and how it came about that they have different contents. According to the endosymbiotic theory, it is believed that two or more prokaryotic cells, living in a symbiotic relationship with each other, ultimately evolved into the mitochondria, present in only eukaryotic cells. One prokaryotic may have engulfed another, created an enclosed membrane for the new organelles that were being created by the presence of two prokaryotic cells.

Segment 3: Connection to the Course

• The endosymbiotic theory is very critical to the evolution aspect of all living things. Because two prokaryotic cells were able to work together in their own beneficial way to make a eukaryotic cell, which now make up all living things besides bacteria and archaea, is very significant. Once the eukaryotic cells were created, evolution was able to take its course, and lead us to where we are now. The creation of the membrane bound nucleus in eukaryotic cells made a huge structural difference, and made complex evolution possible. Overall, both prokaryotic and eukaryotic cells play a major role in the biological world, but it is especially important to appreciate how the eukaryotic cells were created, and how evolution took place after this occurrence.

Thank you for listening to this episode of My AP Biology Thoughts. For more student-ran podcasts and digital content, make sure that you visit