Your heart gets a lot of attention from poets, songwriters, and storytellers, but today we'll learn how it really works. The heart's ventricles, atria, and valves create a pump that maintains both high and low pressure to circulate blood...

See how Aldosterone effects the principal cells of the kidney to raise BP and lower potassium. Rishi is a pediatric infectious disease physician and works at Khan Academy. [13:18]

Learn how the size of a tube (it's radius) is related to its resistance to something flowing through. Rishi is a pediatric infectious disease physician and works at Khan Academy. [8:53]

Learn about how the arteries use nerve impulses to help regulate blood pressure. Rishi is a pediatric infectious disease physician and works at Khan Academy. [12:09]

Learn the important cells and hormones that are working together to control your blood pressure! Rishi is a pediatric infectious disease physician and works at Khan Academy. [14:09]

See how Renin and ACE work to cut Angiotensinogen down to size! Rishi is a pediatric infectious disease physician and works at Khan Academy. [10:19]

See how pressure, flow, and resistance relate to one another and how they each affect the human body. Rishi is a pediatric infectious disease physician and works at Khan Academy. [11:50]

See how increasing resistance in the blood vessels can cause blood pressure to rise over time. Rishi is a pediatric infectious disease physician and works at Khan Academy. [11:25]

See how Angiotensin 2 effects four target "organs" to increase blood pressure. Rishi is a pediatric infectious disease physician and works at Khan Academy. [10:40]

See how ADH acts on blood vessels and the kidney to raise blood pressure. Rishi is a pediatric infectious disease physician and works at Khan Academy. [9:33]

See how ADH acts on blood vessels and the kidney to raise blood pressure. [9:32]