It is the major sight of water absorption.
The correct answer should be the Periderm.
It is not as simple as this, of course and you would be wise to know that periderm is just a part of the overall concept that is bark, because bark is not a biological term.
Answer:
The molecules that bind cellular respiration enzymes act as signals, giving the enzyme information about the cell's energy state. ATP and ADP are examples of molecules that regulate cellular respiration enzymes. ATP, for instance, is a "stop" signal: high levels mean that the cell has enough ATP and does not need to make more through cellular respiration.
This is a case of feedback inhibition in which a product feeds back to shut down its pathways.
