3. Major Functions
• To supply the body with oxygen and dispose of
carbon dioxide
• Respiration- four distinct processes must happen
• PulmonaryVentilation- moving air into and out of the
lungs.
• External Respiration- gas exchange between the lungs
and the blood.
• Transport- transport of oxygen and carbon dioxide
between the lungs and tissues.
• Internal respiration- gas exchange between systematic
blood vessels and tissues.
5. Nose
Providing an airway for
respiration.
Moistening (humidifying)
and warming the entering
air.
Filtering inspired air and
cleaning it of foreign
matters.
Serving as a resonating
chamber for speech.
Housing the olfactory
receptors.
6. Nasal Cavity
Lies in and posterior to the
external nose
The nasal cavity is the inside
of your nose.
It is lined with a mucous
membrane that helps keep
your nose moist by making
mucus so you won't get
nosebleeds from a dry nose.
There are also little hairs that
help filter the air you breathe
in, blocking dirt and dust from
getting into your lungs.
7. Nostril
The primary purpose of
the external nares is to
let air enter the nasal
cavities so it can be
purified and sent to the
next parts of the
respiratory tract.
It also allows different
scents to enter the
nose and reach the
olfactory region of the
nose
8. Oral Cavity
Though not a primary
part of the human
respiratory system, its
functions include
serving as the
secondary passage for
air to enter and exit the
respiratory tract during
inhalation and
exhalation.
9. Pharynx
is a common passageway
shared by both the
digestive and respiratory
systems.
connects the nose,
mouth, and throat.
It extends between the
posterior nasal apertures
and the entrances to the
trachea and esophagus.
its primary purpose is to
let inhaled air pass from
the nasal cavity to the
larynx, windpipe and
then the lungs
10. Larynx
The larynx is the upper end
of the lower airway.
It is continuous with the
trachea below and the
pharynx posterosuperiorly.
Its primary function is to
keep food and drink out of
the airway,
but it evolved the
additional role of sound
production (phonation) in
many animals; hence, we
colloquially think of it as
the “voice box.”
11. Trachea
The primary function of the
trachea is to transport air to
and from the lungs.
Without a trachea, a person
would not be able to
breathe.
In addition to transporting
air, the trachea helps
defend against disease.
The mucus in the trachea
helps capture
microorganisms such as
viruses and harmful
bacteria before they enter
the lungs.
12. Carina of Trachea
is a C-shaped ridge of
cartilage on the trachea.
being the link that connects
the larynx to the primary
bronchi, plays an active part
in letting the air travel in
and out of the lungs.
possesses sensory nerve
endings which cause
coughing if food or water is
inhaled accidently.
13. Right/Left(Primary)
Bronchus
to carry oxygen-rich air
reach the lungs during
inhalation and let
carbon dioxide-rich air
out of the lungs and into
the trachea on its way
out during exhalation.
It is the connection
between the rest of the
respiratory tract and the
lungs.
14. Right/Left Lung
to take oxygen
from the
environment and
transfer it to the
bloodstream.
The lungs are the
major organs of the
respiratory system,
which helps provide
the body with a
continuous supply
of oxygen.
15. Diaphragm
the primary muscle used in
respiration, which is the process of
breathing.
This dome-shaped muscle is located
just below the lungs and heart.
It contracts continually as you
breathe in and out.
is a thin skeletal muscle that sits at
the base of the chest and separates
the abdomen from the chest.
It contracts and flattens when you
inhale.
This creates a vacuum effect that
pulls air into the lungs.
When you exhale, the diaphragm
relaxes and the air is pushed out of
lungs.
16. Physiology of Respiratory
System
The muscles of respiration contract
thereby expanding the chest cavity.
This causes a negative pressure within the
pleural cavity (where the lungs are housed)
which forces the lungs to expand.
The expansion of the lungs reduces the air
pressure in the lungs.
This draws air from the environment which is
at a higher pressure. Air will flow from an
area of high pressure to low pressure.
Air is taken in through the nose and the air is
‘filtered’ and heated in the nasal cavity.
It then passes down the throat and enters
the trachea where it rushes into the bronchi.
17. Physiology of Respiratory
System
The bronchi divides the air flow
between the two lungs.
The air then passes into smaller air
tubes known as bronchioles and empty
into the lungs.
The air enters the tiny air sacs within
the lungs, called alveoli, where oxygen
crosses into the blood and carbon
dioxide empties into the lung.
The respiratory muscles relax and the
chest cavity contracts.
The elastic lungs recoil and pushes air
out through the air passages where it
is emptied into the environment.
