Answer:
it includes geological processes that slowly alter the layout of the physical enviroment and human activity such as land conversion which can help and alter much faster and causes the extinction of many species
Answer:
They can be regulated by different enzymes and feedback.
Explanation:
Most of the transduction pathways are regulated by second messengers and final products. There can be some receptors inside the cell that perceive the excess of some molecules, like Calcium, for example, which can inhibit some signaling pathways, and that's why it's called a third messenger.
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