1. Respiratory System

2. DO NOW
Brain Pop Video: Respiratory System

3. Requires respiratory surface for the exchange of gases (O2 & CO2)
The surface must be:
Thin
Moist
In contact with O2
A transport system

4. Why do we need a respiratory system?
Need O2 in
for cellular respiration
make ATP
Need CO2 out
waste product
food
ATP O2
CO2

5. HUMAN RESPIRATORY SYSTEM
Composed of 2 lungs and the system of tubes that connects them to the outside
* Lungs are in the chest cavity
 diaphragm = muscle that separates lungs from abdomen

6. Lungs capillaries (circulatory system) trachea bronchi bronchioles
alveoli
alveoli

7. Lungs Structure spongy texture alveoli moist lining covered by cilia
high surface area
more absorption of O2
alveoli
small air sacs
moist lining
mucus traps dust, pollen, particles
covered by cilia
hair-like extensions of cells
move mucus upward to clear out lungs

8. Passage of Air: Nose (nostrils) Nasal cavity
Lined with ciliated cells capable of producing mucus
- Hair catches dust particles
- Air passing through the nasal cavity is moistened, warmed and filtered in the nasal cavity

9. Trachea (windpipe) – top part is the larynx with vocal cords
Pharynx (throat) - in the back of the oral cavity where the nasal cavity joins
Trachea (windpipe) – top part is the larynx with vocal cords
cartilage rings hold trachea open
lined with ciliated tissues that sweep dust particles up and out so they may be swallowed or expelled

10. 2 Bronchi – branch from the end of the trachea and lead to the 2 lungs
** also ringed with cartilage and lined with ciliated mucous membrane
Bronchioles – highly branches tubules that subdivide from the ends of the bronchi and become progressively smaller as the pass deeper into the lungs
no cartilage rings

11. Alveoli – air sacs where gas exchange occurs
surrounded by capillaries
carry away oxygen absorbed in the moist lining so it can be transported to body tissues

12. Do Now
Page 5 of the Respiration Packet

13. Breathing: Muscles and ribs + diaphragm = inhalation and exhalation to fill and empty lungs – 2x per minute
Inhale:
Ribs up and out
Diaphragm flattens
Volume increases
Pressure decreases
Exhale:
Ribs down and in
Diaphragm arches
Volume decreases
Pressure increases

14. Moving gases into bloodstream
Inhale
O2 passes from alveoli to blood
by diffusion
Exhale
CO2 passes from blood to alveoli
capillaries
(circulatory system)

16. Gas exchange: Diffusion of gases
Gases move by diffusion from high to low concentration
capillaries are thin-walled tubes of circulatory system
alveoli are thin-walled sacs of respiratory system
capillaries in lungs
capillaries in muscle O2 O2 O2 O2
CO2
CO2
CO2
CO2
blood
lungs
blood
body

17. Negative pressure breathing
Diaphragm moves down & expands chest cavity pulls air into lungs
inhale
exhale

18. Automatic Brain Control
You don’t have to think to breathe!
Primitive parts of brain coordinate breathing
medulla & pons
measure blood pH
CO2 = pH (acid)
coordinate breathing, heart rate & body’s need for energy

19. Breathing and Homeostasis
ATP
Homeostasis
keeping the internal environment of the body balanced
need to balance O2 in and CO2 out
need to balance energy (ATP) production
Exercise
breathe faster
need more ATP
bring in more O2 & remove more CO2
Disease
poor lung or heart function = breathe faster
need to work harder to bring in O2 & remove CO2
CO2 O2

20. Disorders of the Respiratory System
Emphysema
Asthma
Cancer

21. Effects of Smoking Constricts or narrows the blood vessels
Causes blood pressure to rise and make the heart work harder
Circulation deceases
Smoking is the major cause of heart disease
Can cause chronic bronchitis (inflammation of the bronchi)
Reduces life expectancy

22. Smoking Can cause emphysema
Nicotine is addictive and a powerful drug which makes it difficult to quit smoking
May worsen previous conditions such as asthma
Can lead to cancers of the mouth, throat, and lungs

23. Gills: getting O2 out of water
Gills are gas exchange membranes outside of the body
thin tissue
high surface area
must stay wet
lots of blood vessels
gas exchange
O2 into blood
CO2 out to water
water
gills
Just keep swimming…