Each cell expresses, or turns on, only a fraction of its genes. The rest of the genes are repressed, or turned off.
The turned on genes are then first transcribed into messenger RNA by the process of Transcription.
Then the mRNA is Translated into protein by the process called Translation.
This is how the specific genes are expressed.
Explanation:
What would cause a tree to die?
There are 5 factors to which a tree eventually succumbs: death from its environment, death from harmful insects and diseases, death from a catastrophic event, death from age-related collapse (starvation) and of course, death from harvest.
I hope this helps
The growth of plants and formation of land mammals characterized the paleozoic era.