Centriole
In cell biology a centriole (centri- + -ole) is a cylindrical cell structure composed mainly of a protein called tubulin that is found in most eukaryotic cells. An associated pair of centrioles, surrounded by a shapeless mass of dense material, called the pericentriolar material, or PCM, makes up a compound structure called a centrosome.
Centrioles are present in the cells of most eukaryotes, for example those of animals. However, they are absent from conifers (pinophyta), flowering plants (angiosperms) and most fungi, and are only present in the male gametes of charophytes, bryophytes, seedless vascular plants, cycads, and ginkgo.
Most centrioles are made up of nine sets of microtubule triplets, arranged in a cylinder. Deviations from this structure include crabs and Drosophila melanogaster embryos, with nine doublets, and Caenorhabditis elegans sperm cells and early embryos, with nine singlets.
Edouard van Beneden and Theodor Boveri made the first observation and identification of centrioles in 1883 and 1888 respectively, while the pattern of centriole duplication was first worked out independently by Etienne de Harven and Joseph G. Gall c. 1950 The main function of centrioles is to produce aster and spindle during cell division.
Podcasts:
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by Cya
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by Ezio
Cinderella
by: CyaIt's midnight Cinderella but don't you worry none
'Cause I'm Peter Peter the Pumpkin Eater
And the party's just begun
I guess your prince charming
Wasn't after all
'Cause he sure seemed different
Right after the ball
I guess more than horses
Are turnin' into rats
And by the way he's walkin'
I can guess where your slipper's at
It's midnight Cinderella time that you should know
There's gonna be some changes in the way this story goes
It's midnight Cinderella but don't you worry none
'Cause I'm Peter Peter the Pumpkin Eater
And the party's just begun
I'm gonna help you get over
Bein' under that spell
You're gonna learn to love midnight
Inside this pumpkin shell
I gotta few new magic tricks
Your godmother can't do
I'll show you what it means to
Bip, bip, bip, bip, boppity boo
It's midnight Cinderella time that you should know
There's gonna be some changes in the way this story goes
It's midnight Cinderella but don't you worry none
'Cause I'm Peter Peter the Pumpkin Eater
And the party's just begun