The Respiratory System Dr. Wendy Bruffy. Fun Facts Why Do I Yawn? When you are sleepy or drowsy the lungs do not take enough oxygen from the air. This.
(1.4)Human Systems - Respiratory System (p56-59).
Cultures and Lifestyles of Russia. 1-Why does Russia have so many ethnic groups? As the Russian Empire expanded, different people came under its control.
Chapter 18 Respiratory System. What is the Respiratory System? Your respiratory system is made up of the organs in your body that help you to breathe.
The Human Respiratory System
