1. The Respiratory System

2. The respiratory system is the group of organs that takes in oxygen and gets rid of carbon dioxide
Respiration is another name for breathing
Respiration is the transport of oxygen from outside the body to cells and the transport of carbon dioxide and wastes away from the cells
When we inhale, oxygen in the air moves into the blood from the lungs
Oxygen is used for cellular respiration

3. The O₂/C O₂ Exchange

4. When we exhale, carbon dioxide is released from the body
When we inhale, O₂ in the air moves into the blood from the lungs
O₂ leaves the blood and enters the body cell through the capillaries
O₂ is used for cellular respiration
When we exhale, CO₂ is released from the body
CO₂ moves from the body cells to the capillaries
Blood carries CO₂ through the heart and to the lungs
CO₂ moves out of the lung capillaries and into the lungs to be exhaled

5. Parts of the Respiratory System

6. Air enters your respiratory system through your nose and your mouth
Air flows into the pharynx, or throat
The pharynx branches into two tubes
One tube leads to the stomach
The other tube leads to the lungs
The larynx is the part of the throat that holds the vocal chords
When air passes across the vocal chords, they vibrate, making a voice

7. Parts of the Respiratory System

8. The larynx is connected to the trachea, or windpipe
Air flows from the larynx through the trachea to the lungs
The trachea splits into two branches called bronchi (bronchus, singular)
The bronchi connect to each lung
The bronchi branch off into smaller tubes called bronchioles
Bronchioles lead to tiny sacs called alveoli
Alveoli are surrounded by blood vessels
Gases move between the blood vessels and alveoli

9. Parts of the Respiratory System

10. As you breathe, air is sucked into and forced out of the alveoli
Breathing is carried out by the diaphragm and the rib muscles
The diaphragm is a dome-shaped muscle below the lungs
When you inhale the diaphragm contracts, or moves down
The volume of the chest increases
This creates a vacuum and air is sucked in
Exhaling is the reverse process

11. Disorders of the Respiratory System

12. Asthma – condition in which airways are narrowed because of inflammation of the bronchi
Pneumonia – inflammation of the lungs that is usually caused by bacteria or viruses – alveoli fill with fluid
Emphysema – alveoli have been damaged so oxygen cannot pass across into the blood as well as it should – often linked to long term use of tobacco