And that's exactly why epinephrine and norepinephrine are part of a group of molecules that are collectively known as cater colonines. Now, our epinephrine and norepinephrine are also water soluble. And what that basically means is they can easily dissolve inside our blood and they do not actually need any type of protein carrier to transport them inside the blood to their target cell. Now, the fact that they're water soluble and not lipid soluble means that they cannot actually pass across the cell membrane of the target cell and they bind onto receptors on target cell membranes and they create a secondary messenger response to basically initiate some type of effect inside the target cell. So epinephrine and norepinephrine are very similar in the type of response that they create inside our cell and inside our body as a whole. So epinephrine is responsible for increasing the rate of our heart, the rate at which our heart pumps blood, and also the force with which our heart actually pumps that blood.