|
- 积分
- 17983
- 威望
- 17983
- 包包
- 26159
|
本帖最后由 细胞海洋 于 2012-10-6 13:58 编辑
! i) r2 O% p0 ~6 s: u4 Q
0 P: T& T9 t5 J# k& h 3 O9 U8 Y3 S% i& O7 o
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
$ }, @' x" W5 f/ S+ F
, o* E% |2 J- D! T; B7 p. m; v
_9 q0 A" i& M @$ Q9 A$ I" }3 ]3 K[hide][/hide] |
附件: 你需要登录才可以下载或查看附件。没有帐号？注册
-
总评分: 威望 + 20
包包 + 20
查看全部评分
|
发表于 2012-10-5 12:23
发表于 2012-10-8 15:15
