Prokaryotes and eukaryotes are two fundamental types of cells that differ in various ways:
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Nucleus:
- Prokaryotes: Lack a true nucleus. Their genetic material (DNA) is not enclosed within a membrane but is instead located in a region called the nucleoid.
- Eukaryotes: Have a well-defined nucleus that houses their DNA, which is enclosed by a nuclear membrane.
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Cell Size:
- Prokaryotes: Generally smaller in size, typically ranging from 0.1 to 5 micrometers.
- Eukaryotes: Generally larger, usually ranging from 10 to 100 micrometers.
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Organelles:
- Prokaryotes: Lack membrane-bound organelles. They do have ribosomes, but these are smaller and structurally different from those found in eukaryotes.
- Eukaryotes: Contain membrane-bound organelles, such as the endoplasmic reticulum, Golgi apparatus, mitochondria, and lysosomes, which compartmentalize cellular functions.
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Cell Wall:
- Prokaryotes: Most have a rigid cell wall made of peptidoglycan (in bacteria) or other materials (in archaea).
- Eukaryotes: Some have a cell wall (such as plants and fungi), but animal cells do not have a cell wall. Plant cell walls are made of cellulose, while fungal cell walls are made of chitin.
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Reproduction:
- Prokaryotes: Typically reproduce asexually through binary fission, a simple process where a cell divides into two identical cells.
- Eukaryotes: Can reproduce both asexually (through processes like mitosis) and sexually (through meiosis).
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Genetic Material:
- Prokaryotes: Usually have a single circular strand of DNA and may also possess small circular DNA molecules called plasmids.
- Eukaryotes: Have multiple linear chromosomes located within the nucleus.
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Examples:
- Prokaryotes: Bacteria and archaea.
- Eukaryotes: Animals, plants, fungi, and protists.
These differences reflect the evolutionary divergence between prokaryotic and eukaryotic life forms and influence their complexity and functions.