Differentiation in plants refers to the processes by which distinct cell types arise from precursor cells and become different from each other. Plants have about a dozen basic cell types that are required for everyday functioning and survival. Additional cell types are required for sexual reproduction. While the basic diversity of plant cell types is low compared to animals, these cells are strikingly different. For example, some cells such as parenchyma cells retain the potential to respond to environmental and/or hormonal signals throughout their life and, under the right conditions, can be transformed into another cell type (transdifferentiation). Other cells such as the water-conducting vessel elements undergo cell death as part of their differentiation pathway and thus can never transdifferentiate to another cell type
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A molecular clock is a method used by researchers that uses mutation rates in DNA to estimate the length of time that two species have been evolving independently. This provides evidence of evolutionary descent because it can link to common ancestors.
Climate and weather, since the ocean currents circulate warm and cold water around the earth. Kind of like the butterfly affect, one thing happens over there another thing happens over here. I hope that you find this helpful!
The sentence probably saying about polyploid
Polyploid is when the cell duplicates a complete set of chromosome. This will result in one extra chromosome for each kind which makes them triploid, tetraploid or more. The polyploid organism will more likely to die. In the animal, the extra chromosome will cause sexual imbalance and can make it infertile.
