Answer:
Explanation:
A gene can be turned on or off by environmental factors or from other cells that activate proteins known as transcription factors.
<span>By proper application of fertilizers. Soil tests provides the proper application. hope this helps</span>
<span>The woolly lousewort has dense hairs that surround its flowers. These hairs trap the heat from the sun and allow its temperature to be maintined, keeping the flower at a warm enough temperature for it to germinate its seeds.
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I believe it is behavioural isolation. When there are changes within a certain species, e.g. new birdcalls are formed in certain individuals in a species, "traditional" birds may not like such mating calls and only choose to mate with the more common birdcalls from majority of the birds. There are also some birds that may like the new birdcalls, and choose to mate with birds with those birdcalls. They become genetically isolated as they continue such behavior. Eventually, through genetic drift and other mutations, different species form from a single specie.
Hope this helps! :)