Ask A Scientist© Molecular Biology Archive

name         Ronni T.
status       student
age          20s

Question -   I am fighting with my boyfriend
because I say that a chicken egg is a SINGLE cell.  He says that a chicken
egg is made up of multiple cells.  Is it one tiny cell surrounded by
proteins OR, is it one large cell containing the proteins within its large
membrane?  Thanks for your help.


You are right and your boyfriend is wrong...its one cell...the Ostrich egg
is the largest cell on Earth....I think your boyfriend should have to suck
an egg.

PF
=========================================================
This is a great question! However, there is only one cell in a unfertilized 
chicken egg and the rest is by definition of what an is an egg.

The controversy is -does the egg shell membrane encompasses the 
nucleus containing the genetic material and the cytoplasm (together called an 
ovum) or does the ovum have the cell membrane and the yolk and albumen are separate 
structures in birds.  With most mammals, they are together in the cytoplasm.

The yolk and albumen together contain a rich supply of protein and all the other 
nutrients to allow the developing bird an adequate supply for 3 weeks or so. The 
albumen and the york are frequently viewed as large food vacuoles or containers 
and an essential element to the ovum's potential development; and all the 
components are enclosed by one single membrane. 
 
Actually, the ovum is intergrated with the yolk in mostly all organisms, but 
since the yolk is part of many ovum's cytoplasm in most animals and not in 
others, it becomes a matter of definition as to whether the Ostrich's egg is the 
largest living single cell [before development] having the yolk separated from the 
cyctoplasm.
  
Since man makes the definitions of structures, not nature, we find that science
has made the egg or ovum of three or more types by definition.  It so happens that 
with or without the yolk and albumen, the poultry ovum is the largest living cell.  
If you investigate the details, one of the egg (ovum) definitions does make the 
Ostrich Egg a one cell unit.  I'm sure that like so many other definitions in 
science, there is not a complete universally accepted agreement.

Whatever, there is only one cell in the unfertilized chicken egg when it is laid.

Steve Sample
 
Related Web Sites (active Feb. 02):

http://www.wsu.edu/DrUniverse/eggs4.html

http://www.scri.fsu.edu/~jac/Nuclear/whatis/sizes-5.html

http://www.watchtower.org/library/g/1999/9/8a/article_02.htm

http://members.madasafish.com/~grahamwhite/download/clever.html

http://www.vw.cc.va.us/vwkillj/Advisor/chicken%20rep/chickens1.htm