Hi, I know that arterial pressure increases as peripheral resistance increases. This is because blood begins to back up from the point of increased resistance and a greater volume causes greater pressure in the arteries. Also, the more stiff or rigid the artery the greater the pressure change will be. However, how come in many circuits by increasing resistance the voltage (analog of pressure) does not change but rather the current (analog of flow rate) changes. I know voltage does not change because it is a function of the battery. However why and how does current change?, why the difference between the two systems? Thank you. I didn't know whether to put this in the physics or biology forum.