Cells are divided into two broad categories: prokaryotic cells and eukaryotic cells. Prokaryotic cells include the single-cell organism bacteria and archaea. Animal cells, plant cells, protists, and fungi are eukaryotes. Viruses are not included in these categories as viruses are not independently living organisms but are dependent on living cells as hosts in order to replicate.

All living cells share five components: a plasma membrane, cytoplasm, DNA, ribosomes and a cytoskeleton. However, eukaryotes and prokaryotes differ in many different ways.

Eukaryotic cells contain more specialized organelles, such as the endoplasmic reticulum, Golgi apparatus, mitochondria, and lysosomes compared to prokaryotes.

The eukaryotic ribosomes are larger. They consist of a 60S large subunit and 40S small subunit which comes together to form an 80S complete ribosome whereas the prokaryotic cells have 70S ribosomes. The DNA of eukaryotes is contained within a nucleus whereas prokaryotic DNA is found freely in the cytoplasm in a region called the nucleoid.

Prokaryotes also contain extra-chromosomal DNA called plasmids which eukaryotes don’t.