Here's something you might be interested in.
Ask a Hipster — Advice you didn't know you needed
Big Screen — Movie commentary
Blurt — Music's inside track
Booze News — San Diego spirits
Classical Music — Immortal beauty
Classifieds — Free and easy
Cover Stories — Front-page features
Drinks All Around — Bartenders' drink recipes
Excerpts — Literary and spiritual excerpts
Feast! — Food & drink reviews
Feature Stories — Local news & stories
Fishing Report — What’s getting hooked from ship and shore
From the Archives — Spotlight on the past
Golden Dreams — Talk of the town
The Gonzo Report — Making the musical scene, or at least reporting from it
Letters — Our inbox
Movies@Home — Local movie buffs share favorites
Movie Reviews — Our critics' picks and pans
Musician Interviews — Up close with local artists
Neighborhood News from Stringers — Hyperlocal news
News Ticker — News & politics
Obermeyer — San Diego politics illustrated
Outdoors — Weekly changes in flora and fauna
Overheard in San Diego — Eavesdropping illustrated
Poetry — The old and the new
Reader Travel — Travel section built by travelers
Reading — The hunt for intellectuals
Roam-O-Rama — SoCal's best hiking/biking trails
San Diego Beer — Inside San Diego suds
SD on the QT — Almost factual news
Sheep and Goats — Places of worship
Special Issues — The best of
Street Style — San Diego streets have style
Surf Diego — Real stories from those braving the waves
Theater — On stage in San Diego this week
Tin Fork — Silver spoon alternative
Under the Radar — Matt Potter's undercover work
Unforgettable — Long-ago San Diego
Unreal Estate — San Diego's priciest pads
Your Week — Daily event picks
How chicks breathe inside their eggshells
Through their butts
The chick breathes with both the air sac and the allantois.
Matmail: I was getting ready to cook up some eggs the other day, and I started wondering...how do the little chickens breathe inside the shells before they’ve hatched? It seems like a long time for them to hold their breath during the 21 days or so it takes for them to break out of the shell. — Rich, the Net
Let’s back up the truck, Rich. You’re already five miles down the wrong road on this one. The chicklet doesn’t drop out of the hen fully developed in the shell, then struggle for 21 days to get out. In fact it takes 21 days from the time it’s laid for the egg to develop from the fryable, yolk-and-white form into the cute, chirping, fuzzy yellow form. For the first two weeks outside the hen, the thing in the shell hardly even looks like a chick. But you’re right, the developing embryo does need oxygen. And I’m pleased to be the first to tell you that unhatched chicks (and other birds) breathe through their butts.
Around day four after the chicken lays an egg, the embryo develops a structure called an allantois (al- an-toys), a vein-filled sac that grows out of the back end of the bird’s digestive tract. It absorbs oxygen that comes in through the porous egg shell and also excretes wastes. The growing bird can hum along nicely, “breathing” this way until about two days before it hatches. At that time, it breaks the shell’s membrane lining and punctures that little air sac in the fat end of the egg. For a while, the chick breathes with both the air sac and the allantois. When hatch-time comes, it’s weaned itself off the allantois, which dries up and is left behind in the discarded shell.
Here's something you might be interested in.
How chicks breathe inside their eggshells
Through their butts
How chicks breathe inside their eggshells
Through their butts
The chick breathes with both the air sac and the allantois.
Matmail: I was getting ready to cook up some eggs the other day, and I started wondering...how do the little chickens breathe inside the shells before they’ve hatched? It seems like a long time for them to hold their breath during the 21 days or so it takes for them to break out of the shell. — Rich, the Net
Let’s back up the truck, Rich. You’re already five miles down the wrong road on this one. The chicklet doesn’t drop out of the hen fully developed in the shell, then struggle for 21 days to get out. In fact it takes 21 days from the time it’s laid for the egg to develop from the fryable, yolk-and-white form into the cute, chirping, fuzzy yellow form. For the first two weeks outside the hen, the thing in the shell hardly even looks like a chick. But you’re right, the developing embryo does need oxygen. And I’m pleased to be the first to tell you that unhatched chicks (and other birds) breathe through their butts.
Around day four after the chicken lays an egg, the embryo develops a structure called an allantois (al- an-toys), a vein-filled sac that grows out of the back end of the bird’s digestive tract. It absorbs oxygen that comes in through the porous egg shell and also excretes wastes. The growing bird can hum along nicely, “breathing” this way until about two days before it hatches. At that time, it breaks the shell’s membrane lining and punctures that little air sac in the fat end of the egg. For a while, the chick breathes with both the air sac and the allantois. When hatch-time comes, it’s weaned itself off the allantois, which dries up and is left behind in the discarded shell.
Comments