Most of the nephron is permeable to urea except for the cortical portion of the distal tubule. As the filtrate descends into the medulla, urea diffuses into the loop of Henle down its concentration gradient, causing the urea concentration in the tubule to rise.he loop of Henle. The loop of Henle is the portion of the kidney that creates the conditions by which the kidney can form concentrated urine (i.e. urine with an osmolality greater than plasma) later on in the nephron.
Battery Voltage : Normally a charged cell in rest is around 2.1 Volts which yields in 12.6 Volts for a charged battery at rest. When the battery is being charged by the car alternator the voltage will vary usually between 14 and 14.4 Volts.
Everyone says a car battery's voltage is 12 volts but it varies according to how full up it is with electrical charge. A fully-charged car battery in as-new condition can have a voltage of 12.6 volts when it is not delivering any load current. Some import cars only carry a nominal six volts. It will read 12.6 volts with a digital volt meter if it is fully charge and the engine is not running. 12.4 at 75% charge.