1. Respiratory System

2. General Information
Respiration - brings about exchange of gases (oxygen and carbon dioxide) between the blood, the air, and tissues
Cellular respiration – the process that releases energy by breaking down glucose and other food molecules in the presence of oxygen, releasing carbon dioxide, and making ATP
The respiratory system brings the oxygen to the cells and carries the carbon dioxide away

3. Structures of the Respiratory System
Nose, pharynx, larynx, trachea, and bronchi
Carry air to and from the lungs
A. Nose – Where Oxygen first enters your body. Tiny hairs help filter the air and air is moistened and heated by your nose. Your Nose leads into your Nasal Cavity.

4. Pharynx
Gathers air from your Nasal and Oral Cavities and passes it to your Trachea.
Food, water and air can travel through this tube

5. Larynx Also called, “voice box” Made of cartilages
Covered by epiglottis during swallowing
Keeps solids, liquids out of airways
Supports true vocal cords
Exhaled air vibrates them to make sound

6. Trachea Also called “windpipe” Stiffened by C-shaped cartilage rings
Esophagus stuck to posterior surface
Cartilage missing there
Trachea distorted by balls of food as they pass down esophagus to stomach

7. Lungs
Bronchi Tubes- Each tube (one per lung) splits up into many smaller tubes called Bronchiole, like branches on a tree.
Bronchiole- Keep splitting up until they reach your Alveoli.
Composed of millions of tiny air sacs called alveoli which are rich with capillaries
The alveoli are where gas exchange occurs

8. Structures of the Respiratory System
3. Breathing
Movement of air into & out of the lungs
Lungs have no muscle tissue
Diaphragm contracts to form a partial vacuum to pull air into the lungs, the diaphragm relaxes to allow chest cavity to become smaller, making air flow out

10. Diseases of the respiratory system – many
diseases result from smoking tobacco
Nicotine – strong, toxic stimulant drug which increases heart rate and blood pressure (leading to cardiovascular disease)
Carbon monoxide – poisonous gas which blocks the transport of oxygen and carbon dioxide in the blood

11. Tar – a carcinogen (causes cancer)
Emphysema – loss of lung tissue elasticity

13. Review
Homeostasis – the rate of breathing is controlled by the amount of carbon dioxide in the blood
The level of carbon dioxide in the blood is monitored by the medulla oblongata of the brain

14. Review
Increase in carbon dioxide tells the medulla to increase breathing rate until the level decreases
When the medulla senses the decrease in carbon dioxide, this feedback to the medulla decreases the breathing rate