1. Respiration and Excretion
Chapter 4 Section 1
The Respiratory System

2. The Respiratory System
The respiratory system moves oxygen from the outside environment into the body. It also removes carbon dioxide and water from the body. Key Jobs: Taking in Oxygen Removing Carbon Dioxide and Water

3. The Path of Air Pharynx Trachea Bronchi Lungs
As air travels from the outside environment to the lungs, it only take a few seconds, and passes through the following structures:
Nose
Pharynx
Trachea
Bronchi
Lungs

4. The Respiratory System

5. The Nose Facts about the nose: 2. Nasal Cavity produces mucus.
1. In the Nasal Cavities the air is warmed.
2. Nasal Cavity produces mucus.
3. Mucus keeps air moist, the cavity damp, and it traps dust.
4. Cilia: hair like extensions that make a sweeping motion down to the throat.

6. The Pharynx Facts about the Pharynx:
1. Also called the throat.
2. Only part of the respiratory system that is shared with another system.
3. This is where the Epiglottis is located, just above the trachea.

7. The Trachea 2. Also called windpipe.
Facts about the Trachea:
1. The Larynx is at the top of Trachea, also known as the voice box.
2. Also called windpipe.
3. Has ridges made of cartilage that strengthen the trachea and keep it open.
4. Lined with cilia and mucus.
5. Only air should be here at this point.

8. The Bronchi, Alveoli, and Lungs
Quick Questions
1. Large passages that lead to the lungs?
2. Main organs of the respiratory system?
3. Tiny sacs specialized for movements of gases?

9. Gas Exchange
After air enters an alveolus, oxygen passes through the wall of the alveolus and then through the capillary wall into the blood. Carbon dioxide and water pass from the blood into the alveoli. This whole process is known as gas exchange.

10. Gas Exchange continued
Alveoli have a large amount of surface area, like the small intestine. If you spread out the alveoli on a flat surface they would have a surface area of about 70 square meters.

11. How you Breath
Facts about the Lungs:
1. In an average day you may breath more than 20,000 times.
2. The diaphragm is the dome-shaped muscle that plays an important role in breathing.
3. When you breath, the actions of your rib muscles and diaphragm expand or contract your chest. As a result, air flows in or out. (remember this also helps the flow of blood in the body)

12. Breathing and Speaking
Larynx: the voice box, is located in the top part of the trachea, underneath the epiglottis. Vocal cords : connective tissue that stretch across the larynx, when they vibrate it creates your voice.

13. Respiratory Tract

14. Respiration