用现代遗传学的理论来解释拉马克的用进废退

用现代遗传学的理论来解释拉马克的用进废退
用现代遗传学的理论来解释拉马克的用进废退

用现代遗传学的理论来解释拉马克的用进废退
现代遗传学也是建立在达尔文的进化论,自然选择学说基础上的,基因进化的动力也是源于自然选择.而用进废退其实是结果,而非原因.基因以及表型是由于被选择并保留了下来才体现出了用进的现象,废退也是同样的道理.

从现代生物学来讲，拉马克的用进废退是可以理解的。从某一方面来说是对的，因为有科学家发现让一代小老鼠听到某种音乐后产生疼痛感，到第三代小老鼠，也就隔代遗传后听到这种音乐也会有疼痛感产生。
其次，表观遗传学的建立。这是一种不依赖DNA改变来改变遗信息的调控。这是可以获得性遗传。所以拉马克的用进废退是可以说成立的。下面就是Epignetic的含义。
In biology, and s...

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从现代生物学来讲，拉马克的用进废退是可以理解的。从某一方面来说是对的，因为有科学家发现让一代小老鼠听到某种音乐后产生疼痛感，到第三代小老鼠，也就隔代遗传后听到这种音乐也会有疼痛感产生。
其次，表观遗传学的建立。这是一种不依赖DNA改变来改变遗信息的调控。这是可以获得性遗传。所以拉马克的用进废退是可以说成立的。下面就是Epignetic的含义。
In biology, and specifically genetics, epigenetics is the study of heritable changes in gene activity that are not caused by changes in the DNA
sequence; it also can be used to describe the study of stable,
long-term alterations in the transcriptional potential of a cell that
are not necessarily heritable. Unlike simple genetics based on changes to the DNA sequence (the genotype), the changes in gene expression or cellular phenotype of epigenetics have other causes. The name epi- (Greek: επί- over, outside of, around) -genetics.[1]
The term also refers to the changes themselves: functionally relevant
changes to the genome that do not involve a change in the nucleotide
sequence. Examples of mechanisms that produce such changes are DNA methylation and histone modification, each of which alters how genes are expressed without altering the underlying DNA sequence. Gene expression can be controlled through the action of repressor proteins that attach to silencer regions of the DNA. These epigenetic changes may last through cell divisions
for the duration of the cell's life, and may also last for multiple
generations even though they do not involve changes in the underlying DNA sequence of the organism;[2] instead, non-genetic factors cause the organism's genes to behave (or "express themselves") differently.[3]
(There are objections to the use of the term epigenetic to describe
chemical modification of histone, since it remains unclear whether or
not histone modifications are heritable.)[4]
One example of an epigenetic change in eukaryotic biology is the process of cellular differentiation. During morphogenesis, totipotent stem cells become the various pluripotent cell lines of the embryo, which in turn become fully differentiated cells. In other words, as a single fertilized egg cell – the zygote – continues to divide, the resulting daughter cells change into all the different cell types in an organism, including neurons, muscle cells, epithelium, endothelium of blood vessels, etc., by activating some genes while inhibiting the expression of others.[5]
In 2011, it was demonstrated that the methylation of mRNA plays a critical role in human energy homeostasis. The obesity-associated FTO gene is shown to be able to demethylate N6-methyladenosine in RNA. This discovery launched the subfield of RNA epigenetics.[6][7]
来自
http://en.wikipedia.org/wiki/Epigenetic

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