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Respiratory system introduction

7 videos
3 skills
Did you know that your right lung is larger than your left? That’s because the majority of your heart is on the left side of your body, and your left lung is slightly smaller to accommodate it. The lungs take in oxygen and help you breathe out carbon dioxide. Humans have an intricate respiratory system, with hundreds of millions of tiny air sacs called alveoli, where all of the magic happens. These videos will introduce you to the lungs, and show how they help you survive.

Meet the lungs

VIDEO 9:36 minutes
Every time you take a breath, oxygen makes it way into your lungs. Follow along on that journey! Rishi is a pediatric infectious disease physician and works at Khan Academy.

People and plants

VIDEO 9:30 minutes
Learn more about photosynthesis and cellular respiration through a classic story: Jack and the Beanstalk. Rishi is a pediatric infectious disease physician and works at Khan Academy.

The bronchial tree

VIDEO 12:47 minutes
Follow the path of an oxygen molecule as it makes its way from your mouth down to an alveolus! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Inhaling and exhaling

VIDEO 12:59 minutes
Find out exactly why air goes in and out of the lungs. Rishi is a pediatric infectious disease physician and works at Khan Academy.

How does lung volume change?

VIDEO 8:10 minutes
Learn about how muscle contraction and lung recoil actually help the lungs change their volume with every breath! Rishi is a pediatric infectious disease physician and works at Khan Academy.

The lungs and pulmonary system

VIDEO 20:33 minutes
The pulmonary system including the lungs, larynx, trachea, bronchi, bronchioles, alveoli and thoracic diaphragm

Introductory respiratory system quiz

PRACTICE PROBLEMS
Questions

Intermediate respiratory system quiz

PRACTICE PROBLEMS
Intermediate Lung Quiz

Advanced respiratory system quiz

PRACTICE PROBLEMS
Advanced Lung Quiz