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 hypothesis is classified as an ¨If, Then¨ statement. Example: If I punch a brick, then it will hurt.
Yes most of them do. That is one of the main reasons why dogs get spayed/neutered. In order to give birth, You need to of had your period first. So the animals that can give birth have a period. I don't know how long it is though. I am also not sure about fish, just mammals.
Answer:
Because of gravity, in matter does not leave the system so the chemical matter we have on Earth will always be here
