What Prokaryotic and Eukaryotic Cells Have in Common:
- Both have DNA as their genetic material (it’s DNA that tells cells what kind of cells they should be).
- Both are covered by a cell membrane.
- Both contain RNA.
- Both are made from the same basic chemicals: carbohydrates, proteins, nucleic acid, minerals, fats and vitamins.
- Both have ribosomes (the structures on which proteins are made).
- Both regulate the flow of the nutrients and wastes that enter and leave them.
- Both have similar basic metabolism (life processes) like photosynthesis and reproduction.
- Both require a supply of energy.
- Both are highly regulated by elaborate sensing systems ("chemical noses”) that make them aware of the reactions within them and the environment around them.
Prokaryotic and Eukaryotic Cells Differences:
AGE DIFFERENCES
Scientists believe that prokaryotic cells (in the form of bacteria) were the first life forms on earth. They are considered “primitive” and originated about 3.5 billion years ago. That's 2 billion years earlier than eukaryotic cells and billions of years before our earliest ancestors, the hominids.
Eukaryotic cells contain two important things that prokaryotic cells do not: a nucleus and organelles (little organs) with membranes around them.
We Can see the structural differences in this page:http://www.cod.edu/people/faculty/fancher/CellStructure.htm
DNA arrengament
Although both eukaryotic and prokaryotic cells contain DNA, the DNA in eukaryotic cells is held within the nucleus. In prokaryotic cells, the DNA floats freely around in a unorganized manner.
Size
Eukaryotic cells are, on average, ten times larger than prokaryotic cells.
New Discoveries
Until recently, it was thought that only eukaryotic cells existed in multi-cell groups like in organs and tissues. But recent discoveries suggest that some prokaryotic cells do too. This is just one more example of how new discoveries are always changing what we know – or think we know.
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