1. NursingBulletin:
Respiratory System

3. Functions of Respiratory
System
A. Primary functions
1. The respiratory system provides oxygen for
metabolism in the tissues.
2. The respiratory system removes carbon
dioxide, the waste product of metabolism.
B. Secondary functions
1. The respiratory system facilitates sense of
smell.
2. The respiratory system produces speech.
3. The respiratory system maintains acid-base
balance.
4. The respiratory system maintains body water
levels.
5. The respiratory system maintains heat
balance.

4. Physiology
• When you inhale, air enters through the
nose or mouth. As air is breathed through
the nose, it is warmed, moistened and
filtered by the hairs that line the nostrils.
The air then passes into the nasal
passages. Air from the nasal passages
and mouth enters the pharynx and passes
downward to the larynx.

5. Upper Respiratory System

6. Upper Respiratory System
NOSE:
Openings: exterior: anterior nares
to nasopharynx: posterior nares
Linings: Ciliated Mucosa (CILIA)
Sinuses Draining into the Nose: (Paranasal
Sinuses)
a. Frontal b. Maxillary
c. Sphenoidal d. Ethmoidal
Functions:
a. Sinuses are air-filled cavities within the hollow
bones that surround the nasal passages.
b. Sinuses provide resonance during speech.

7. NOSE
• Filters, warms and humidifies air
• First defense against foreign particles
• Inhalation for deep breathing is to be done via
nose
• Exhalation is done through the mouth
• Serves as passageway for incoming and outgoing
air, filtering, warming, moistening, and chemically
examining it.
• Organ of smell (Olfactory receptors located in the
nasal mucosa
• Aids in phonation
• Once the air enters the nose and mouth, it travels into
the pharynx and larynx. The structures of the upper
respiratory tract are moist with mucus and are lined
with cilia. The CILIA constantly sweep the airways, in
an upward motion, to facilitate elimination of bacteria,
dust and other particles

8. Pharynx (Throat)
Behind oral and nasal cavities
• Nasopharynx
– behind nose
– soft palate, adenoids and eustachian tube
• Oropharynx
– from soft palate to base of tongue
– palatine tonsils (guard the body against
invading organism
• Laryngopharynx
– base of tongue to esophagus
– where food and fluids are separated from air
– bifurcation of larynx and esophagus

9. Pharynx
• Serves as a passageway and entrance to
the respiratory and digestive tracts
• Aids in Phonation
• Tonsils function to destroy incoming
bacteria and detoxify certain foreign
proteins

10. Larynx
LOCATION: at the upper end of the trachea, just below the
pharynx
Structure:
1. Cartilages: nine pieces arranged in a boxlike formation
Thyroid cartilage: largest (Adam’s apple)
Epiglottis (the lid cartilage) The epiglottis is a leaf-shaped,
elastic structure that is attached along one edge to the top
of the larynx. Its hingelike action prevents food from
entering the trachea (aspiration) by closing over the glottis
during swallowing. The epiglottis opens during breathing
and coughing.
Cricoid (the signet ring cartilage)
2. Vocal Cord
False: folds of mucous linings
True: fibroelastic bands stretched across the hollow
interior of the larynx; the paired vocal cords (folds) and the
posterior arythenoid cartilages make up the GLOTTIS; the
slit between the vocal cords, through which air enters and
leaves the lower respiratory passages, is the rima glottidis

11. Larynx
Functions:
a. Voice production: during expiration, air
passing through the larynx cause the
vocal cords to vibrate; short, tense cords
b. Serves as a passageway for air and as
the entrance to the lower respiratory tract

12. LOWER RESPIRATORY SYSTEM

13. TRACHEA
A. Structure
1. Walls: smooth muscle;
contain C-shaped rings
of cartilages at
intervals; these keep
the tube open at all
times but do not
constrict the
esophagus, which is
directly behind the
trachea
2. Lining: Ciliated Mucosa

14. TRACHEA (WINDPIPE)
B. Functions
This armored tube allows air to pass beyond the larynx to where it
divides into the left and right bronchi. The protective ‘C's of
cartilage also provide protection to the digestive system's
esophagus right behind it.
• The larynx goes directly into the trachea or the windpipe.
• The trachea is a tube approximately 12 centimeters in length
and 2.5 centimeters wide.
• The trachea is kept open by rings of cartilage within its walls.
• Similar to the nasal passages, the trachea is covered with a
ciliated mucous membrane.
• Usually the cilia move mucus and trapped foreign matter to the
pharynx.
• After that, they leave the air passages and are normally
swallowed.
• The respiratory system cannot deal with tobacco smoke very
keenly.
• Smoking stops the cilia from moving. Just one cigarette slows
their motion for about 20 minutes. The tobacco
smoke increases the amount of mucus in the air passages.
When smokers cough, their body is attempting to dispose of the
extra mucus.

15. MAINSTEM BRONCHI
Mainstem
• Begin at the carina
• RIGHT BRONCHUS is slightly wider, shorter, & more
vertical than the left bronchus
• Mainstream bronchi divide into 5 secondary or lobar
bronchi that enter each of the 5 lobes of the lung
• The bronchi are lined with cilia which propel mucus up &
away from the lower airway to the trachea where it can be
expectorated or swallowed
• The bronchi enter the lungs and spread into a treelike fashion
into smaller tubes called bronchial tubes.
• 3. Bronchioles
a. Bronchioles branch from the secondary bronchi and subdivide
into the small terminal and respiratory bronchioles.
b. The bronchioles contain no cartilage and depend on the
elastic recoil of the lung for patency.
c. The terminal bronchioles contain no cilia and do not
participate in gas exchange

16. ALVEOLAR DUCTS AND ALVEOLI
• ALVEOLAR DUCTS & ALVEOLI
• - used to indicate all structures distal to the
terminal bronchiole
• Alveolar ducts branch from the respiratory
bronchioles
• Alveolar sacs which arise from the ducts
contain clusters of alveoli which are basic units
of gas exchange
• Cells in the walls of the alveoli secrete
surfactant
• - phospholipid CHON the reduces the
surface tension in the alveoli
• - without surfactant the alveoli would
collapse

18. LUNGS
• Lungs
a. The lungs are located in the pleural cavity in the thorax.
b. The lungs extend from just above the clavicles to the diaphragm,
the MAJOR MUSCLE OF INSPIRATION.
c. The RIGHT lung, which is larger than the left, is divided into THREE
lobes, the upper, middle, and lower lobes.
d. The LEFT lung, which is narrower than the right lung to
accommodate the heart, is divided into two lobes.
e. Innervation of the respiratory structures is accomplished by the
PHRENIC NERVE, the VAGUS NERVE, and the THORACIC nerve.
f. The parietal pleura lines the inside of the thoracic cavity, including
the upper surface of the diaphragm.
g. The visceral pleura covers the pulmonary surfaces.
h. A thin fluid layer, which is produced by the cells lining the pleura,
lubricates the visceral pleura and the parietal pleura, allowing them
to glide smoothly and painlessly during respiration.
i. Blood flow through the lungs occurs via the pulmonary system and
the bronchial system.

19. ACCESSORY MUSCLES
• ACCESSORY MUSCLES OF
RESPIRATION
• SCALENE MUSCLES
• Elevate the first 2 ribs
• STERNOCLEIDOMASTOID MUSCLES
• Raises the sternum
• TRAPEZIUS & PECTORALIS MUSCLES
• Fix the shoulders

20. The Respiration Process
• THE RESPIRATION PROCESS
• the diaphragm descends into the abdominal cavity during
inspiration causing (-) pressure in the lungs
• the (-) pressure draws the air from the area of greater pressure
(THE ATMOSPHERE) into an area of lesser pressure (THE
LUNGS)
• In the lungs, air passes thru the terminal bronchioles into the
alveoli to oxygenate the body tissues
• At the end of inspiration, the diaphragm & intercostal muscles
relax & the lungs recoil
• As the lungs recoil, pressure within the lungs becomes greater
than atmospheric pressure, causing the air which now
contains the cellular waste products of CO2 & H2O to move
from the alveoli in the lungs to the atmosphere
• Expiration is a passive process

21. Respiratory System Recap
Questions
• The exchange of oxygen and carbon
dioxide between air, blood and body
tissues is known as:
• A. Inspiration
• B. Expiration
• C. Respiration
• D. Perspiration

22. Respiratory System Recap
Questions
The trachea possesses:
• Skeletal muscles
• Pleural fluid
• C-shaped rings of cartilage
• Walls with stratified epithelium

23. Respiratory System Recap
Questions
Breathing is an automatic process controlled
by the:
• Medulla
• Hypothalamus
• Lymph Nodes
• Hippocampus

24. Respiratory System Recap
Questions
• The upper respiratory system tract
consists of all the following EXCEPT:
• Nostrils
• Larynx
• Pharynx
• Trachea

25. Respiratory System Recap
Questions
• Which structure helps facilitate speaking?
• Larynx
• Pharynx
• Trachea
• Epiglottis

26. Respiratory System Recap
Questions
• The respiratory tract is moist with ______
and lined with ____ that sweep particles
out of the airways.
• Surfactant; Cells
• Fluid; Squamous tissue
• Mucus; Cilia
• Surfactant; Cartilage

27. Respiratory System Recap
Questions
• This protective structure helps to keep
food and fluids out of the airways
• Glottis
• Esophagus
• Epiglottis
• Larynx

28. Respiratory System Recap
Questions
• These are tiny air sacs at the ends of the
bronchioles. They are responsible for
oxygen diffusion:
• Bronchi
• Alveoli
• Interstitial Spaces
• Bronchus

29. Respiratory System Recap
Questions
• These thin sheets of epithelium cover the
outer surface of the lungs and the inside of
the thoracic cavity:
• Surfactant
• Mediastinum
• Cilia
• Pleura

30. Respiratory System Recap
Questions
• The pleura produce a lubricating fluid
called:
• Mucus
• Surfactant
• Mediastinum
• Squamous

31. Respiratory System Recap
Questions
• This structure warms, moistens and filters
inhaled air:
• Trachea
• Lungs
• Nose
• Epiglottis

32. Respiratory System Recap
Questions
• Which of the following does not occur
during inhalation?
• The ribs are pulled up and out
• Air pressure within the chest cavity is
reduced
• The diaphragm is pulled upward
• The chest cavity becomes larger

33. Respiratory System Recap
Questions
The Adam’s apple is part of which laryngeal
cartilage?
• Epiglottis
• Thyroid
• Cricoid
• Pharynx

34. Respiratory System Recap
Questions
• Which of the following statements about
human lungs is incorrect?
• They are elastic
• They are muscular
• They are surrounded by pleura
• They are above the diaphragm

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