Your heart gets a lot of attention from poets, songwriters, and storytellers, but today Hank's gonna tell you how it really works. The heart’s ventricles, atria, and valves create a pump that maintains both high and low pressure to circulate blood from the heart to the body through your arteries, and bring it back to the heart through your veins. You'll also learn what your blood pressure measurements mean when we talk about systolic and diastolic blood pressure. Table of Contents Heart's Ventricles, Atria and Valves Create a Pump 3:25 Maintains Both High and Low Pressure 3:25 Blood Circulates From the Heart to the Body Through Your Arteries 4:47 Blood Circulates From the Body to the Heart Through Your Veins 4:49 Systolic and Diastolic Blood Pressure 7:58 Crash Course Psychology posters available now at DFTBA.com! http://www.dftba.com/crashcourse *** Crash Course is now on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever: Mark Brouwer, Jan Schmid, Anna-Ester Volozh, Robert Kunz, Jason A Saslow, Christian Ludvigsen, Chris Peters, Brad Wardell, Beatrice Jin, Roger C. Rocha, Eric Knight, Jessica Simmons, Jeffrey Thompson, Elliot Beter, Today I Found Out, James Craver, Ian Dundore, Jessica Wode, SR Foxley, Sandra Aft, Jacob Ash, Steve Marshall ***SUBBABLE MESSAGES*** TO: My Student FROM: Earle Check out www.youtube.com/amorsciendi for supplementary content. -- TO: Everyone FROM: Magnus Krokstad Keep dreaming! ***SUPPORTER THANK YOU!*** Thank you so much to all of our awesome supporters for their contributions to help make Crash Course possible and freely available for everyone forever: Damian Shaw, Taylor Garget, Emily Barker, Librarifan, Damian Shaw, Courtney Spurgeon, juliagraph, Katherine Allen, Stephen DeCubellis, Vanessa Benavent -- Want to find Crash Course elsewhere on the internet? Facebook - http://www.facebook.com/YouTubeCrashCourse Twitter - http://www.twitter.com/TheCrashCourse Tumblr - http://thecrashcourse.tumblr.com Support Crash Course on Patreon: http://patreon.com/crashcourse CC Kids: http://www.youtube.com/crashcoursekids