Some say Preload = End-Diastolic Pressure, others say Preload = End-Diastolic Volume, so which one is it? Watch and find out! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Learn the difference between blood flow (volume/time) and perfusion (volume/time/amount of tissue). Rishi is a pediatric infectious disease physician and works at Khan Academy. [10:31]

Learn about how resistance can be added up in series and in parallel (similar to electrical circuits!). Rishi is a pediatric infectious disease physician and works at Khan Academy. [10:33]

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]

Find out what a systolic and diastolic blood pressure mean. Rishi is a pediatric infectious disease physician and works at Khan Academy. [6:21]

Find out how compliance allows arteries to store elastic energy (and lower pressure). [9:54]

Watch the pressure in the left heart go up and down with every heart beat! This video lecture focuses on following the blood as it moves from the left artium and exploring the pressure as it moves through the heart. [14:58]

See how increasing resistance in the blood vessels can cause blood pressure to rise over time. [11:25]

See how Angiotensin 2 effects 4 target 'organs' to increase blood pressure. [10:40]

See how Renin and ACE work to cut angiotensinogen down to size. [10:18]

Learn the key triggers for ADH secretion. [15:05]

Learn about four lifestyle changes that can be made to lower blood pressure in this video. Understand how a good diet, exercise, losing weight and quitting smoking can all help patients manage hypertension. [6:35]

A video [7:08] explaining what hypertension is, how it is measured, and how to know if systolic and diastolic blood pressure is high or low.

A video [7:08] explaining what hypertension is, how it is measured, and how to know if systolic and diastolic blood pressure is high or low.

What do your blood pressure numbers mean? In this video, learn the difference between systolic and diastolic pressure and when these numbers are in the danger zone. [6:13]

This video looks at factors that influence shock and decreased tissue perfusion. [7:39]

This video contains a very detailed drawing of the heart to explain blood flow. [9:47]

Find out what a systolic and diastolic blood pressure mean. Rishi is a pediatric infectious disease physician and works at Khan Academy.

An overview of a diagnosis and treatment of shock.

A video reviewing over the difference between blood vessels and how they all work together in the circulatory system. [7:42]

This lesson will identify what blood pressure is and factors that affect blood pressure. It is 1 of 5 in the series titled "Blood Pressure."

Paul Andersen shows you how to use a sphygmomanometer to measure the systolic and diastolic blood pressure. The the describes the elements of the laboratory portion. The temperature is gradually lowered and the respiration rate of a...

This lesson will explain the steps that occur when your heart muscle contracts. It will investigate the cardiac cycle and the cardiac conduction system. It is 1 of 2 in the series.