Respiratory
system
CH. 37.3
VIDEO CLIP
HTTP://WWW.YOUTUBE.COM/WATCH?V=O2OCGGJBIUK
Function
exchange of oxygen
and
carbon dioxide
between the blood,
the air.
Respiration
Cellular level
Organism level

the release of energy:
from the breakdown of glucose in the
presence of oxygen.
 gas exchange:
The respiratory system consists of
 nose
 pharynx
 larynx
 trachea
 bronchi
 lungs
pollen
Air entering
the respiratory system
must be:
warmed, moistened, and filtered.
 Mucus
moistens air and traps
particles of dust or smoke.
dust
 Cilia
sweep particles and mucus to
the throat.
mucus
 Mucus
and particles are either
swallowed or spit out.
 Smog
Pollution
 Coal
 Asbestos
Pharynx vs. Larynx
The Pharynx
1st
 serves as a
passageway for both
air and food.
The Larynx
 It is at the top of the
trachea.
 contains two elastic folds of
tissue:
vocal cords.
The epiglottis:
C O V E R S T H E E N T R A N C E TO T H E T R A C H E A
W H E N Y O U S WA L L O W.
Don’t speak:
while you are eating!!!
Why
chocking
http://auditoryneuroscience.com/?q=vocal_folds
Vocal cords
V I D E H T T P : / / W W W . Y O U T U B E . C O M / W AT C H ? V = X S S D E E Y _ 0 X C
The 2 Bronchi
(bronchus singular)
•
TWO LARGE AIR
PA S S A G E S
•
E A C H L E A D S I N TO
ONE OF THE LUNGS
•
SUBDIVIDE= BRANCH
INTO
BRONCHIOLES
Purpose of branching?
INCREASE SURFACE AREA
•
A P P R O X I M AT E LY A T E N N I S C O U R T
S U R FA C E A R E A
Functional units of the
lungs
Alveolus
 MILLIONS OF TINY
AIR SACS AT THE
END OF THE
BRONCHIOLES

IS WHERE
THE GAS EXCHANGE
TAKES PLACE
O2
from the alveoli diffuses into the blood
CO2
in the blood diffuses into the alveolus.
O2
CO2
Respiratory and circulatory
systems work together
Hemoglobin
 Protein present in
red blood cells
 It has
Fe (iron)
heme part
that binds to O2
What is the diaphragm?
F L AT M U S C L E
T H AT S E PA R AT E S
T H E A B D O M I N A L C AV I T Y
FROM
T H E T H O R A C I C C AV I T Y.
H T T P : / / W W W . Y O U T U B E . C O M / W AT C
H ? V = H P - GC V W 8 P RY
Breathing
The movement of air
into and out of the lungs.

Is driven by air pressure:
∆
the diaphragm contracts
∆
This expands the volume of
the chest cavity.
∆
Creating a partial vacuum
inside the cavity.
http://www.youtube.com/watch?v=hHQ
BFFu2ekw
The medulla oblongata
 Controls breathing
 Monitors carbon dioxide in the
blood.
 As carbon dioxide increases,
nerve impulses make the
diaphragm contract, bringing air
into the lungs.
 The higher the carbon dioxide
level, the stronger the
impulses.
Emphysema
is most often caused by smoking and long-term exposure
to air pollution.
 Lung tissue
looses elasticity
 alveoli are unable to
hold their functional
shape upon
exhalation.
Lung cancer
 Lung cancer is deadly
because its cells can
spread to other
locations.