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本帖最后由 细胞海洋 于 2012-10-6 13:58 编辑 5 j8 y: u$ `. J$ w: Y g7 l' Y
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As it develops from a single-celled zygote to a mature plant embryo, the thale cress Arabidopsis thaliana passes through a stage during which phylogenetically very ancient genes are preferentially expressed. This corroborates recent work on animals demonstrating a similar period of embryogenesis that coincides with what nineteenth-century zoologists recognized as a phase in development — at least in vertebrates — in which embryos of all species looked very similar. It seems that animals and plants have independently converged on a similar way of managing gene expression as they transform from a single-celled zygote to a multicellular organism, even though their morphological development is very different. Cover art by www.sistersofdesign.de / F7 O! e9 |0 k6 R U; R( L( y
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发表于 2012-10-5 12:23
发表于 2012-10-8 15:15
