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prokaryotic cells

Prokaryotic Cells

The distinction in prokaryotics cells which defines it as unique is the lack of a cell nucleus and organelles contained within individual membranes. The majority of prokaryotic organisms are single celled organisms although this varies in some life forms that have a multicellular life cycle. An example of one of these exceptions is with cyanobacteria which is commonly known as blue-green algae and is essential in the ocean’s ecosystems. All cell components are contained within the central cell membrane where they essential float freely within the cell. Ribosomes within a prokaryotic cell are also generally smaller than their counter parts in eukaryotic cells.


Since prokaryotic cells lack complex structure, DNA within a prokaryote is contained within the nucleoid which is a relatively simple single strand molecule (compared to the complex double helix structure we are most often taught). Prokaryotes also contain a plasmid which is a unique DNA molecule which can reproduce independently from the cell’s chromosomal DNA cycle and contains two strands. These are most common in bacteria.

Although prokaryotic life forms are commonly thought of as simply single celled organisms, they are known for their ability to aggregate in a community such as is found in cyanobacteria where they create an envelope of a polymer like slime to provide additional protection. These biofilms help to unite a community of prokaryotes into microcolonies.

prokaryotic reproduction

Prokaryotic Reproduction

Prokaryotic reproduction usually occurs asexually through a process known as binary fission. The parent cell begins the process of binary fission by first cloning it’s single DNA strand. The two DNA strands then attach themselves to the cell membrane adjacent from each other and the cell membrane begins to expand. Once the total cell size is almost doubled the middle of the membrane begins a pinching process to separate both sides. Once closed the cells have completed their replication process and have now formed two daughter cells.