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Circulatory system introduction

1 article
1 program
9 videos
3 skills
No organ quite symbolizes love like the heart. One reason may be that your heart helps you live, by moving ~5 liters (1.3 gallons) of blood through almost 100,000 kilometers (62,000 miles) of blood vessels every single minute! It has to do this all day, everyday, without ever taking a vacation! Now that is true love. Learn about how the heart works, how blood flows through the heart, where the blood goes after it leaves the heart, and what your heart is doing when it makes the sound “Lub Dub.”

Meet the heart!

VIDEO 10:09 minutes
Find out exactly where the heart rests in your body and what it does. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Flow through the heart

VIDEO 7:51 minutes
Learn how blood flows through the heart, and understand the difference between systemic and pulmonary blood flow. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Two circulations in the body

VIDEO 12:25 minutes
Learn the difference between the pulmonary and systemic circulatory systems in the body. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Lub dub

VIDEO 9:50 minutes
Ever wonder why the heart sounds the way that it does? Opening and closing of heart valves makes the heart rhythm come alive with its lub dub beats... Rishi is a pediatric infectious disease physician and works at Khan Academy.

Layers of the heart

VIDEO 12:13 minutes
Take a closer look at the heart, explore some of its interesting features and get to know the three layers that make up the heart. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Arteries vs. veins - what's the difference?

VIDEO 11:09 minutes
Learn some important differences between arteries (high pressure/low volume) and veins (low pressure/high volume). Rishi is a pediatric infectious disease physician and works at Khan Academy.

Arteries, arterioles, venules, and veins

VIDEO 7:43 minutes
Learn the differences between these blood vessels! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not ...

Circulatory system and the heart

VIDEO 14:57 minutes
Introduction to the circulatory system and the heart

Intermediate Circulatory System Quiz

PRACTICE PROBLEMS
Intermediate Circulatory System Quiz

Advanced circulatory system quiz

PRACTICE PROBLEMS
Advanced heart quiz