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Name: Christa
Status: Student
Grade:  Other
Location: GA
Country: United States
Date: Summer 2009

Are there any living organisms that developed without the use of an egg?

Yes, there are tons of them. Bacteria, fungi, plants, several invertebrates, the list goes on and on. Reproduction can occur by fission (where a cell splits), budding (a mini-cell grows from the parent), spore formation (a tight package of the stuff needed for life) and other means too. Search on the net for 'asexual reproduction' to read more about how organisms can reproduce without eggs.

And (I can't resist) the egg existed before the chicken.

Hope this helps,

Yes, there are plenty of living organisms that develop without the use of an egg.

Eggs are part of sexual reproduction in animals. Organisms that utilize asexual reproduction do not use eggs as part of their reproductive cycle. An example is bacteria. A bacteria cell reproduces by copying its genetic material and splitting its chromosomes and organelles into two new cells. This process does not use eggs (or sperm).

Plants do not use eggs during reproduction either, although they do have male and female counterparts to the sperm and egg that play similar roles to those found in sexually reproducing animals.

When you consider how many organisms are plants and how many reproduce asexually, really, very few organisms use eggs in development!

Ian Farrel

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