Topic: Respiratory System Aim: How does breathing occur? Do Now: Explain the process of gas exchange in the respiratory system. http://www.youtube.com/watch?v=EtrsdmuhcT8 http://www.youtube.com/watch?v=XTMYSGXhJ4E HW: Read pages 574 – 576. Write a paragraph discussing the cause and treatment of each disorder.
Did you know… Your lungs contain almost 1500 miles of airways and over 300 million alveoli. During normal breathing, the speed that you exhale air is about 4 miles per hour. Plants are our partners in breathing. We breathe in air, use the oxygen in it, and release carbon dioxide. Plants take in carbon dioxide and release oxygen.
Breathing Inhalation air travels into lungs Exhalation air pushed out of lungs Involves the diaphragm & rib cage muscles
Inhalation
Diaphragm moves DOWN (contracts) Rib cage expands Air rushes in
Exhalation
Diaphragm moves UP (relaxes) Rib cage relaxes Air forced out
Maindex
REMEMBER… Inhale DOWN Exhale UP
What controls breathing rate?
Brain MEDULLA Detects the level of CO2 in the blood
3. Which gas regulates breathing rate? http://www.youtube.com/watch?v=Lygr-rAtHgA http://www.youtube.com/watch?v=D0mUHzmnN_4&feature=related Review: Which way does the diaphragm move during inhalation? During exhalation? 2. What happens to pressure in the chest cavity during inhalation? During exhalation? 3. Which gas regulates breathing rate?
1 2 3 4 1 = TRACHEA 3 = ALVEOLI 2 = BRONCHI 4 = DIAPHRAGM BELL JAR MODEL OF THE RESPIRATORY SYSTEM 1 2 3 4 1 = TRACHEA 3 = ALVEOLI 2 = BRONCHI 4 = DIAPHRAGM
BELL JAR MODEL OF THE RESPIRATORY SYSTEM EXHALATION INHALATION
EXHALATION INHALATION BELL JAR MODEL OF THE RESPIRATORY SYSTEM Diaphragm moves UP Pressure increases Air forced up & out Diaphragm moves DOWN Pressure decreases Air enters