Answer:
The acidic environment in the stomach stops the action of the amylase enzyme.
The stomach will secrete digestive juice that contain hydrochloric acid and digestive enzyme such as pepsin to digest protein.
The HCL create an acidic environment that will deform the ionic and hydrogen bond of the amylase which cause the enzyme to be denatured.
The answer is signal transduction. It is also known as cell signaling. It is the transmission of molecular signals beginning from a cell's exterior to its interior. Signals got by cells must be transferred efficiently into the cell to make certain a suitable response. This step is started by the cell-surface receptors.
The guard cell is responsible for controlling the size of the stomata in leaves. These do so as a result of an interaction between potassium ions and water in and around the cells. When potassium ions accumulate inside the guard cells the water potential inside these cells is lower than that of the outside and as a result, water has to be taken in. This makes the guard cells turgid which in turn stretches them and results in the opening of the stomata. Meanwhile, when potassium ions accumulate outside the cell, the opposite scenario results. Water from inside the cell moves out, making the guard cells flaccid, thus causing these to cover (and effectively close) the stomata.
