1. Respiratory System Intro

2. Objective: SWBAT describe common functions of the respiratory system as well as the basic organs.

3. Respiratory System Function 1. It provides for oxygen and carbon dioxide exchange between the blood and air. 2. It serves for speech and other vocalizations. 3. It provides the sense of smell, which is important in social interactions, food selection, and avoiding danger. 4. By eliminating carbon dioxide, it helps control the pH of body fluids.

4. Function Continued 5. The lungs carry out a step in the synthesis of a vasoconstrictor called angiotensin II, which helps to regulate blood pressure. 6. Breathing creates pressure gradients between the thorax and abdomen that promote the flow of lymph and venous blood 7. Taking a deep breath and holding it while contracting the abdominal muscles helps to expel abdominal contents during urination, defecation, and childbirth.

5. Principal Organs (important ones) Nose Pharynx Larynx Trachea Bronchi Lungs

6. The flow of oxygen Within the lungs, air flows along a dead-end pathway consisting essentially of bronchi  bronchioles  alveoli. Incoming air stops in the alveoli, exchanges gases with the bloodstream across the alveolar wall and then flows back out

7. Divisions/Zones The conducting division of the respiratory system consists of those passages that serve only for airflow, essentially from the nostrils through the bronchioles. The respiratory division consists of the alveoli and other distal gas- exchange regions. The airway from the nose through the larynx is often called the upper respiratory tract (respiratory organs in the head and neck), and the regions from the trachea through the lungs compose the lower respiratory tract (the respiratory organs of the thorax).

8. 8 The Respiratory Organs Conducting zone Respiratory passages that carry air to the site of gas exchange Filters, humidifies and warms air Respiratory zone Site of gas exchange Composed of Respiratory bronchioles Alveolar ducts Alveolar sacs Conducting zone labeled