Difference between Prokaryotic & Eukaryotic Cell

Contrasting Traits and Structures of Prokaryotes versus Eukaryotes

Feb 2, 2009

What specifically are the main differences between prokaryotic and eukaryotic cells? Here is a side by side comparison to simplify mastering the basics of cell structure.

Cells are the basic units of life, and although there are many different forms of specialized cells, there are only two true types of cells — prokaryotes and eukaryotes.

There are several Suite101 articles which discuss the basics of these two types of cells, including:

However, neither of the above articles presents a simple, point by point comparison of prokaryotic and eukaryotic cells. Well, here it is. There is also another corresponding article featuring the similarities of prokaryotic and eukaryotic cells.

Note that this list does not contain every conceivable difference, but rather focuses on the main features that distinguish prokaryotic from eukaryotic cells.

Differences between Prokaryotic and Eukaryotic Cells

Cell Walls – Although most prokaryotes, and some eukaryotes, have a cell wall — cell-supporting structures located outside the plasma membrane, cell walls are composed of different materials, based on the type of organism. Bacteria (prokaryotes of the domain Eubactera) have cell walls that contain the molecule peptidoglycan. No other type of organism has a cell wall containing this molecule. Prokaryotes in the domain Archea have cell walls, but they are made of materials other than peptidoglycan. Eukaytotic animal cells do not have cell walls. Eukaryotic plants and fungi have cells walls, made of cellulose and chitin, respectively.

Centriomes and Centrostomes (some Eukaryotes) – Animal and some fungal cells possess these structures, whereas plants, algae, fungi and prokaryotes do not have them. Centrioles (two together make a centrosome) are involved in cytoskeleton production and cell division of animal cells.

Energy-related Organelles (Eukaryotes) – Mitochondria and chloroplasts are membrane-bound organelles, so are not found in prokaryotes. Mitochondia are found in nearly all eukaryotic cells (other than a few oddball parasites) and chloroplasts are found only in eukaryotes that photosynthesize (capture sunlight energy and turn it into food). These two energy-related organelles have their own DNA and are believed to have originally been independent prokaryotes that formed a symbiotic (mutualistic) relationship with another cell. This is called the endosymbiotic theory.

Endomembrane System (all Eukaryotes) – Although both prokaryotes and eukaryotes have a plasma membrane, a phospholipid bilayer that separates the inside from the outside of the cell, only eukaryotes have additional membrane-bound organelles within the cell, including the nuclear membrane, endoplasmic reticulum, Golgi apparatus, lysosomes and vesicles.

Evolution – Eukaryotic cells are more evolutionarily advanced, having arisen from prokaryote-like predecessors.

Location of Genome – The genome (chromosomes) of a eukaryote resides within the nucleus, a membrane bound structure which encloses the genetic material within the nuclear membrane. Prokaryotes don’t have a nucleus. Their genetic material (called a nucleoid) floats freely within the cytoplasm.

Type of Genome – Although the genomes of all living organisms are composed of deoxyribonucleic acid (DNA), eukaryotes can have their DNA present in few to many linear chromosomes (humans have 46 chromosomes). Prokaryotes typically have a single, circular chromosome.

Plasmids (Bacterial Prokaryotes) – A plasmid is an extra piece of ‘bonus’ genetic material that is separate from the genome and not use for day to day functions of the cell. This small piece of DNA typically confers some advantage to the bacteria, such as antibiotic resistance, virulence factors or augmenting conjugation.

Size – Nearly all prokaryotes are much smaller in size that a eukaryotic cell. Prokaryotes usually range between 1 – 10 micrometers, whereas eukaryotic cells range from 10 micrometer – 1 millimeter.

The copyright of the article Difference between Prokaryotic & Eukaryotic Cell in Biology is owned by Tami Port. Permission to republish Difference between Prokaryotic & Eukaryotic Cell in print or online must be granted by the author in writing.

May 13, 2009 1:13 AM

Guest :

you must make the difference more clearer or better yet put it in table form

May 13, 2009 11:11 AM

Tami Port :

Regarding the comment requesting more information or a table: The information is all here. Unfortunately, Suite101 articles cannot be formatted to include a table. But better yet...make your own table of this differences based on the wealth of information in the article. If you are a biology student, this will help you learn about these differences.

Jun 8, 2009 1:54 PM

Guest :

The two comparative articles made learning the difference so clear. And putting them into a chart just helped so much more. Thanks for all the hard work and effort toward our success!

Jun 16, 2009 6:09 AM

Guest :

i just want to ask Tami Port because I heard from many people that the main difference between eukaryotic and prokaryotic is the nucleus.. It is also what I have understood on your other link http://microbiology.suite101.com/article.cfm/prokaryotic_and_eukaryotic_cel ls
that is why I am very confused about this.. please answer it as soon as possible..
thanks..

Jun 16, 2009 1:13 PM

Tami Port :

Regarding the June 16 comment:

This article lists all of the main differences between prokaryotes and eukaryotes. The differences are listed in alphabetical order, so the fact that the cell wall is listed first does not mean that this is the most important difference. Yes, prokaryotes don't have a membrane-bound nucleus (or any membrane-bound structures). Prokaryotes have a naked genome, called a nucleoid, floating in the cytoplasm. Eukaryotes do have a membrane-bound nucleus. This presence or absence of a nucleus is one of the most visible differences when viewing cells through a microscope. But there are many differences between prokaryotes and eukaryotes in addition to how the genetic material is packaged. Those differences are outlined in this article.

Jun 21, 2009 1:35 PM

Guest :

thank you for answering my question tami port (regarding my June 16 question) I wish you could stll help many other students..

Jul 7, 2009 2:40 AM

Guest :

dont fight for just one topic. what for?. the article is so good.

Jul 26, 2009 1:57 AM

Guest :

there is no difference beetween prokaryotic & eukaryotic cell

Aug 10, 2009 4:39 AM

Guest :

you should make a table so it will be more clearer

Aug 14, 2009 2:51 AM

Guest :

...please make it clear...it is better if you will tabulate it okay...

Sep 8, 2009 7:27 PM

Guest :

Truely speaking, i had come to this site to make my concept clear about two different cells but after learning i am more confused . I request to format articles in easiest method i.e can be in table so everyone can understand.