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Animals: Human Respiratory System

Animals: Human Respiratory System

Author: Nathan Lampson

When we breathe, our respiratory system intakes oxygen and exhales carbon dioxide. In this tutorial, you will learn about the function and structure of the human respiratory system, and see how different muscles, such as the lungs and diaphragm, work together to help us breathe and make sounds.  Concepts such as alveoli, bronchi and lungs are crucial to the study of basic science.

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The respiratory system's job is to move oxygen from outside the body (in the environment) into the body and to exhale waste (water, carbon dioxide).


The respiratory system begins with the nose.  Air is drawn in through the nose and debris in the air are trapped in mucus.  The process of drawing air into the respiratory system is called inhalation.


Air drawn in through the nose makes its way to the trachea.  The trachea is a tube (known as the windpipe) that has ridges to strengthen it and prevent it from folding shut.  Tiny hairs in the trachea clean particles out of the air to prevent them from entering farther into the body.


The bronchi is an area where the trachea splits into two passage ways that travel to the left and right lungs.


Lungs collect oxygen from the air and move it into the bloodstream so that it can be transported throughout the body.  Inside the lungs, bronchi split into smaller tubes called bronchioles.  Branches of bronchioles eventually end in tiny sacs called alveoli.

This image labels complex features of the respiratory system.  Important features to note include the trachea, bronchi (left and right), alveoli, and lungs.

Animals: Human Respiratory System