dl9006

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an egg remains at metaphase II until fertilized by a sperm right?

so shouldn't an egg contain 23 chromosomes and 46 chromatids since the 23 chromosomes haven't been pulled apart at metaphase II?
 
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dl9006

dl9006

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please don't post garbage
 

4thMolar

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yes, from what I remember from embryology, I believe you are right. Is there something you saw that didn't agree with this statement?
 
May 22, 2009
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The eggs all arrest at prophase I until puberty. Then once a month, few of the eggs (only one of each will actually be released) go on with meiosis I and then arrest at metaphase II. When stimulated by sperm entry, the meiotic division is complete. That's how I remember it.
 
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dl9006

dl9006

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yes, from what I remember from embryology, I believe you are right. Is there something you saw that didn't agree with this statement?
this was actually from the Destroyer 2008 #158.

Question:
An egg cell will contain?
a)23 chromosome 46 chromatids
b)23 chrom 23 chromatids
c) 46/ 46
d)46/23
e)48/24


ans B

Explanation: egg and sperm cells are haploid. thus has 23 chromosome and 23 chromatids.


i guess it all depends on what stage of meiosis the egg is in.

so if the question was re-worded and asked about the egg before fertilization, answer A would be correct right?
 
Jun 14, 2009
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an oocyte is not an egg. In humans a primary oocyte is arrested at prophase I until ovulation, then proceeds to metaphase II. At this stage it is still not considered a true egg; instead it is still called an oocyte. A true egg is haploid, meiosis complete, and in humans this stage is very transient because it does not complete until fertilization. An egg in any animal is the reproductively competent, meiosis-complete haploid 1N gamete that unites with a sperm.

It doesnt really matter what stage of meiosis it's in because an egg is not an egg until meiosis II finishes. Any time before that it is an oocyte.