Overview of eukaryotic cells and how they differ from prokaryotic cells (nucleus, organelles, and linear chromosomes).


What would it be like to live in a one-room cabin? Well, things would probably be pretty simple. You would eat, sleep, work, and relax in a single room—which might be a bit cramped, but would certainly make cleaning the house a snap!
Prokaryotic cells, the simple cells of organisms like bacteria, are sometimes compared to one-room cabins: they don't have internal membranes, so they’re like a single room with no walls to carve it upstart superscript, 1, end superscript. If we extend this analogy to eukaryotic cells, the more complex cells that make up plants, fungi, and animals, we'll find that they're a definite step upward in the real estate market.
Just as a large family home is split into many rooms with different purposes (bedrooms, bathrooms, kitchen, living room, etc.), so eukaryotic cells contain a variety of different compartments with specialized functions, neatly separated from one another by layers of membrane. This organization lets each compartment maintain its own conditions, the ones it needs to carry out its job.
For instance, compartments called lysosomes, which act as recycling centers for the cell, must maintain an acidic pH in order to dispose of cellular waste. Similarly, structures called peroxisomes carry out chemical reactions called oxidation reactions and produce hydrogen peroxide, both of which would damage the cell if they weren’t safely stored away in their own “room.”
The ability to maintain different environments inside a single cell allows eukaryotic cells to carry out complex metabolic reactions that prokaryotes cannot. In fact, it’s a big part of the reason why eukaryotic cells can grow to be many times larger than prokaryotic ones.

Prokaryotic vs. eukaryotic cells

What are the key features of eukaryotic cells? Unlike prokaryotic cells, eukaryotic cells have:
  1. A membrane-bound nucleus, a central cavity surrounded by membrane that houses the cell’s genetic material.
  2. A number of membrane-bound organelles, compartments with specialized functions that float in the cytosol. (Organelle means “little organ,” and this name reflects that the organelles, like the organs of our body, have unique functions as part of a larger system.)
  3. Multiple linear chromosomes, as opposed to the single circular chromosome of a prokaryote.
Eukaryotic cells are much more complicated than those of prokaryotes. They are packed with a fascinating array of subcellular structures that play important roles in energy balance, metabolism, and gene expression.
In the articles and videos that follow, we’ll take a tour through eukaryotic plant and animal cells, exploring the unique structures they contain and the role that each structure plays in the life of the cell.
Already know what part of the cell you want to visit? Use the list below to jump to your region of interest:
Diagram of a typical animal cell:
Diagram of an animal cell with components lettered.
Image modified from OpenStax Biology.
Diagram of a typical plant cell:
Diagram of a plant cell with components labeled.
Image modified from OpenStax Biology.


This article is a modified derivative of “Eukaryotic cells,” by OpenStax College, Biology (CC BY 3.0). Download the original article for free at http://cnx.org/contents/185cbf87-c72e-48f5-b51e-f14f21b5eabd@9.85:18/Biology.
The modified article is licensed under a CC BY-NC-SA 4.0 license.

Works cited:

  1. Raven, P. H., Johnson, G. B., Mason, K. A., Losos, J. B., and Singer, S. R. (2014). Cell structure. In Biology (10th ed., AP ed., p. 63). New York, NY: McGraw-Hill.

Additional references:

Eukaryotic cells. (2014). In Scitable. Accessed July 21, 2016. http://www.nature.com/scitable/topicpage/eukaryotic-cells-14023963.
Raven, P. H., Johnson, G. B., Mason, K. A., Losos, J. B., and Singer, S. R. (2014). Cell structure. In Biology (10th ed., AP ed., pp. 59-87). New York, NY: McGraw-Hill.
Reece, J. B., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V., and Jackson, R. B. (2011). A tour of the cell. In Campbell Biology (10th ed., pp. 92-123). San Francisco, CA: Pearson.