-All signal transduction cascades are shut down immediately so as to prevent the cell from mounting a response.
-Cells are unable to respond quickly to hormones, and therefore signal transduction cascades always occur over a long time.
-Cells have to be able to function alone, because they are unable to work together in a coordinated fashion.
-Cells often have to respond very quickly to changes in their internal and external environments.
Since pressure is force per unit area, blood pressure could be thought as the force exerted by the blood to the surface area of your blood vessels. When your blood vessels dilate, it means that they expanded. The result would be faster flow of blood. When this happens, the force of the blood is not any more concentrated on your blood vessels because there is more room available.
Think of a faucet where tap water flows. When you stopper the faucet with your finger, you feel the force of the water. The pressure builds up as manifested by the sound your faucet makes. But when you release your finger, the water rushes through and flows faster. The pressure is released. Therefore, when your blood vessels are dilated, your blood pressure decreases.
