Eukaryotes require size for their diverse collection of structures.
At the very least, a eukaryotic cell contains a nucleus, a membrane transport system including the endoplasmic reticulum and golgi, mitochondria, and the ever-present (and often transitory) vacuoles and vesicles. Without so much cellular furniture to deal with, a prokaryote can afford to be the "bachelor's suite of life".
As a case study, a single mitochondrion is roughly the size of a prokaryotic cell, and eukaryotes can have dozens of these.
Mitochondria are, in fact, postulated as symbiotic prokaryotes adapted to life inside larger eukaryotic cells.
Their lack of dining set, chesterfield, and a china cabinet does not mean prokaryotes are less equipped to deal with survival, any less than a bachelor's suite is less condusive to survival than a three-bedroom apartment; in fact, they gain distinct advantages from their simplicity.
This is not a complete list of the differences between prokaryotic and eukaryotic cells. The tables comparing these types of cells (in general) include detail at about the level of detail expected for A-Level Biology.
For more about cells see prokaryotic cell structure, animal cell structure, and an introduction to cell division.
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I found this among some notes from undergrad that I was cleaning up.
The flagellum of a bacterial cell is much simpler than the flagellum of a eukaryotic cell.
A prokaryotic flagellum consists of a single cylinder of protein subunits (flagellin).
Prokaryotic cell flagella are "tails" used for movement.
They are surrounded by (not protruding through, or outside of) the cell membrane and contain microtubules and motor proteins that enable complex movements.
Depending on their size, these structures are either flagella (longer than the cell; few in number) or cilia (smaller but more numerous).
The tiny prokaryote can do everything a eukaryote can do, and usually much faster.
Their cellular membrane performs the ATP synthesis duties of a mitochondrion.
DNA is constantly replicating in the bacterial cytoplasm, with neither the elegance nor the encumbrance of formal mitosis.
The environment is small enough that reactions can occur in the hydrophilic cytoplasm or hydrophobic plasma membrane with satisfactory frequency.
Some eukaryotic organisms, such as Paramecium, require a contractile vacuole to maintain water balance, while a bacterium achieves this passively with a semirigid cell wall that holds in hydrostatic pressure., keeping the cell from bursting.
Therefore neither the DNA of prokaryotic cells nor any of the sites of metabolic activity within a prokaryotic cell are enclosed by a separate membrane.
Instead, everything is openly accessible within the cell e.g.
ribosomes are scattered throughout the cytoplasm (not attached to the surfaces of the endoplasmic reticulum as in animal cells). The types and quantities of other membrane-bound organelles vary with the type of cell. endoplasmic reticulum (SER , RER), golgi apparatus, mitochondia, lysosomes, peroxisomes and microbodies & chloroplasts (in photosynthetic cells only; not in animal cells).
Examples of prokaryotic cells include the cells of many bacteria, e.g. The cell nucleus is surrounded by a double membrane.
Most cells have only one nucleus but some specialized cells e.g. (Multinucleate cells are called coenocytes.) The nucleus controls the activity of the cell and contains DNA and a nucleolus - or multiple nucleoli - in which ribosome units, ribosomal RNA and transfer RNA are produced. The nucleus is continuous with the endoplasmic reticulum.
It's an answer from a test I wrote back in 2nd-year microbiology in 2001, and I think quite relevant as a primer on some biological concepts.
This essay explains: In a eukaryotic organism, the membrane-bound organelles that are its trademark effectively raise the surface area-to-volume ratio, the traditional limit to cell size.
In addition, they provide a high level of segregation and organisation for chemical reactions within the cell, arguably increasing efficiency and definitely increasing possible size.
If environments are controlled by vacuoles and other organelles, reactions between reagents that would be too rare in the cytoplasm to react can be much faster, simply because the effective volume is smaller.
Prokaryotes lack this ability, so in order for reactions involving low-concentration metabolites to occur, the cell must remain fairly small.
That is, they are the smallest units that can be alive.
There are many different types of biological cells - see diagram, right. plant cells and animal cells) there are many different forms of specialized biological cells.
Biological cells can be classified as either Introductory school biology courses include topics about animal cells, plant cells and differences between plant and animal cells. Examples of animal cells include muscle fibres, neurones and blood cells incl. Other types of eukaryotic cells include the cells of fungi e.g. There are many species of protoctists - the biological "Protoctista Kingdom" consists of aquatic microorganisms that are neither plant nor animal nor fungi nor bacteria.