1. The Respiratory System
Science 10

2. HOW MANY TIMES DO YOU INHALE AND EXHALE ON AVERAGE IN ONE MINUTE?
TRY IT!
THE ANSWER IS … 15

3. The Respiratory System
What would cause this number to increase?
Physical activity
Stress
What does the respiratory system do?
provide oxygen to the body
remove carbon dioxide from the body

4. Structural Features Nose Mouth Pharynx (throat)
The main parts of the respiratory system are:
Nose
Mouth
Pharynx (throat)
Trachea (rings of cartilage)
Bronchi
Lungs

5. Structural Features nasal cavity mouth ciliated epithelial cells
pharynx
trachea
alveoli
bronchus
lung
bronchioles

6. Structural Features Cilia in Action
Cells that line the trachea and bronchi have cilia (hairlike projections) and cells that produce mucus
Cilia and mucus help filter out foreign material that might enter the system
Cilia in Action

7. Pathway of Gases in System
Inhale oxygen
Oxygen diffuses into blood in the lungs
Blood carries oxygen throughout body
Oxygen diffuses out of blood into cells
Carbon dioxide diffuses out of cells into blood
Carbon dioxide travels in blood to lungs
Carbon dioxide diffuses out of blood into alveoli
Blood picks up oxygen and cycle continues

8. Gas Exchange
the main purpose of the respiratory system is gas exchange
each bronchi ends in tiny air sacs called alveoli
these sacs allow the diffusion of oxygen and carbon dioxide
single alveoli
alveoli
red blood cells
capillary
capillary network

9. Breathing
involves alternately bringing air into the lungs (inhalation) and pushing air out of the lungs (exhalation)
involves muscles of the ribs and the diaphragm (a large sheet of muscle below the ribs)
involuntary process that we can override, but only temporary (try it! how long can you hold your breath for?)

10. Inhalation and Exhalation

11. Breathing Inhalation Exhalation volume of the lungs increase
muscles of ribs contract
diaphragm flattens
Exhalation
lung volume decreases
muscles of ribs relax
diaphragm is dome-shaped

12. Control of Breathing
Breathing is controlled by a part of the brain that detects carbon dioxide in the blood
As carbon dioxide increases, brain sends signals to the diaphragm, muscles between the ribs, and the heart
This increases breath rate and heart rate which decreases the amount of carbon dioxide and increases the amount of oxygen

13. Diseases of the Respiratory System
Tuberculosis
An infectious disease caused by bacteria entering body when you breathe
Symptoms: fever, cough, weight loss, tiredness, chest pain
Cancers
Caused by tobacco smoke
SARS
Symptoms are flulike
Respiration Video

14. Amazing Facts About the Respiration System
The right lung is slightly larger than the left.
Hairs in the nose help to clean the air we breathe as well as warming it.
The highest recorded "sneeze speed" is 165 km/h
The surface area of the lungs is roughly the same size as a tennis court.
The capillaries in the lungs would extend 1,600 kilometres if placed end to end.
We lose half a litre of water a day through breathing. This is the water vapour we see when we breathe onto glass.
The breathing rate is faster in children and women than in men.

15. Textbook Questions
Answer Pg. 95 #1 – 6

16. CYL 1 – 6 pg. 95
Name the main organs and structures of the respiratory system.
nasal cavity
pharynx
mouth
trachea
bronchi
lungs
alveoli

17. CYL 1 – 6 pg. 95
What is the role of the epithelial tissue that lines the trachea and bronchi?
secrete mucus and filter out foreign material
How does an animal’s respiratory system depend on its circulatory system?
circulatory system carries oxygen and carbon dioxide that are exchanged in respiratory system

18. CYL 1 – 6 pg. 95
Explain the difference between breathing and gas exchange.
breathing is intake and output of air
gas exchange involves diffusion of oxygen into the blood and carbon dioxide out of the blood

19. CYL 1 – 6 pg. 95
(a) Why is an x-ray insufficient to make a positive diagnosis of tuberculosis?
an x-ray can show TB, but other conditions (such as pneumonia) can look like TB on an x-ray
(b) What test is required to confirm a diagnosis of TB?
stomach and lung secretions must be examined to confirm TB

20. CYL 1 – 6 pg. 95
Describe the similarities and differences between the respiratory systems of humans and fish.
both exchange oxygen and carbon dioxide
fish takes in oxygenated water, humans take in air
humans breathe air in and out for gas exchange, in fish gas exchange occurs as water flows over their gills