Thread Tools Display Modes
Old 08-26-2001, 07:59 PM
Join Date: Jun 2000
Location: Silicon Valley
Posts: 4,190
This must be obvious. Is it really one single cell? What is all the extra material, beyond the DNA, mitochondria, etc. I assume it's food for growth; is that true? If it is one cell, does it actually split into two yolks and albumins (sp?), etc.? Or is the actual reproducing part a reasonable size (i.e. very small) And in that case, I assume the actual cell is in the yolk; true?
Old 08-26-2001, 08:17 PM
Charter Member
Join Date: Apr 2000
Location: Slithering on the hull
Posts: 26,283
It is one cell, with a big support system. No, the yolk doesn't split, nor does the white. The yolk is the food source for the developing embryo, which starts microscopically on the surface of the yolk. The embryo grows, the yolk shrinks.
Old 08-26-2001, 08:24 PM
Join Date: May 2001
Location: Eastern SF Bay Area
Posts: 4,219
Technically, a chicken egg (or any other bird or reptile egg) is not a cell at all. The "amniotic egg" is composed of several parts which effectively allow for a fluid environment for the developing fetus.
The actual fetus (or the cell which will become the fetus) is housed in the amnion (thus the "amniotic egg" bit), a mebranous compartment within the egg. Other such compartments include the allantois (kind of a waste receptacle), the yolk sac (this houses the egg yolk), and the chorion, which encloses everything (this is the thin "skin" that you find on hard-boiled eggs, just inside the shell).
In a chicken egg, the yolk, of course, is the fluid-filled yolk sac, which is a nutrient source for the developing fetus. The fetus, when present, would be attached to the yolk sac (actually, the yolk sac is attached to the fetus, but you get the idea).
Old 08-26-2001, 08:46 PM
Charter Member
Join Date: May 2000
Location: Heartland of New Jersey
Posts: 1,892
And those blood spots you sometimes find?

Those come from the yolk breaking out of the ovary (technically breaking out of follicular sacs of the ovary) before it moves through the oviduct to be fertilized and have the shell deposited. Usually, the yolks break through at areas of limited arterial involvement (called stigma) but occasionally a blood vessel gets in the way, and voila! Blood spot.

Since this occurs before fertilization, blood spots are poor indicators of fertile eggs. Just thought I'd share.
Old 08-27-2001, 01:04 AM
Join Date: Jun 2000
Location: Silicon Valley
Posts: 4,190
Excellent info; thanks all. So what is the purpose and destiny of the white of the egg? Is it cushion? Does it remain until hatching?
Old 08-27-2001, 01:43 AM
Join Date: May 2001
Location: Eastern SF Bay Area
Posts: 4,219
The egg-white, aka albumen, is essentially a protein soup which, in addition to the yolk, supplies proteins, vitamins, water, and minerals to the developing embryo. The yolk is primarily protein and fat.

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 09:16 AM.

Send questions for Cecil Adams to: [email protected]

Send comments about this website to:

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Copyright 2018 STM Reader, LLC.

Copyright © 2017
Best Topics: torpedo vs missile prescription strength motrin creative stripper names lockable liquor cabinet abnormal means walmart mongoose bicycles low altitude parachute poison for groundhogs cox versus utilities in monopoly 5w20 vs 5w30 nfl referee wristband what happened to john edward psychic performance chips that work magic the gathering deckmaster price guide cost to upgrade garmin nuvi maps shaving cream on a plane best cat food for stinky poop phone books dont leave bruises ear still feels blocked after syringing how long can cooked meat stay at room temperature how to get cockroaches out of microwaves where do lock washers go