1. 13
The Respiratory
System: It's a Gas

2. Respiratory System
 Respiratory system's
primary function: to
transport oxygen
from atmosphere to
bloodstream to be
utilized by cells,
tissues, organs for
process of cellular
respiration, which is
necessary to sustain
life

3. Respiratory System
 Respiratory system
moves 12,000 quarts
of air per day in and
out of lungs
 Respiratory system
removes waste gas—
carbon dioxide—so it
doesn't build up in toxic
levels

4. Cellular Respiration Needs
Oxygen
 Cellular respiration
depends on continuous
supply of oxygen,
found in abundance in air
we breathe
 Using oxygen produces
carbon dioxide, which
would become toxic if
allowed to build in
bloodstream; must be
removed

5. Cardiopulmonary System
 Respiratory system
closely related to
heart and
circulatory system;
they are
sometimes
grouped together
as cardiopulmonary
system

6. Anatomy of Respiratory
System
 Components of
respiratory system:
 Two lungs that serve
as vital organs
 Upper and lower
airways that conduct
gas in and out of the
system
 Terminal air sacs
called alveoli
surrounded by
network of capillaries
that provide for gas
exchange

7. Anatomy of Respiratory
System
 Components of
respiratory system:
 Thoracic cage that
houses, protects,
facilitates function for
the system
 Muscles of
breathing that
include the main
muscle, the
diaphragm, and
accessory muscles

8. Figure 13-1
The various components of the
respiratory system
Watch Video on
“Respiratory
System”
http://www.youtube.com/watch

9. Ventilation versus
Respiration

10. Ventilation versus
Respiration
Ventilation: bulk
movement of air into
and out of lungs
where gas exchange
takes place

11. Ventilation versus
Respiration
Respiration:
process of gas
exchange, where
oxygen added
to blood and
carbon dioxide
removed

12. External Respiration
versus Internal Respiration

13. External Respiration
versus Internal Respiration
External respiration:
gas exchange in lungs
occurs between blood
and air in the external
atmosphere

14. External Respiration
versus Internal Respiration
Internal respiration:
oxygenated blood
transported
internally via
cardiovascular system
to cells and tissues;
oxygen moves into
cells as carbon dioxide
removed

15. Table 13-1 Gases in the
Atmosphere
Air contains many
gases,
predominantly
nitrogen, which is a
support gas that
keeps lungs open
with its constant
volume and
pressure

16. Table 13-1 Gases in the
Atmosphere
Next highest
concentration
found in air is
oxygen,
essential to life;
carbon dioxide
is found in very
small
concentrations

17. Figure 13-2
Contrast of ventilation and
external and internal respiration
We have reserve
of oxygen to
last 4 to 6
minutes; after
that we will die if
we don't get
more oxygen

18. The Airways and Lungs
 Respiratory
system is series of
branching tubes
called bronchi
and bronchioles

19. The Airways and Lungs
 Airways transport
atmospheric gas
deep within lungs
to small air sacs
called alveoli,
which represent
terminal end of
respiratory
system

20. The Airways and Lungs
 Each alveolus is
surrounded by
capillaries;
combination called
alveolar-capillary
membrane;
represents
connection
between
respiratory and
cardiovascular
systems

21. Structures of Upper Airway

22. Function of Upper Airway
Structures
Nose
Mouth
Larynx
Pharynx

23. Figure 13-3
The upper airway and vocal cords

24. Upper Airways of
Respiratory Tract
 While some
people breathe
through their
mouths, we are
meant to
breathe through
our noses
 Rigid structure
made of
cartilage and
bone

25. Upper Airways of
Respiratory Tract
 Nasal cavity:
behind nose,
divided into
three main
regions
Vestibular
Olfactory
Respiratory

26. Figure 13-4
The nasal regions

27. Regions of the Nose
Three Main Regions

28. Vestibular Region of Nose
 Vestibular region: located
inside nostrils and
contains coarse nasal
hairs that act as first
line of defense for
respiratory system
 These hairs (vibrissae)
covered with sebum,
greasy substance
secreted by sebaceous
glands of nose
 Sebum helps trap
particles; keeps hairs
soft and pliable

29. Olfactory Region of Nose
 Olfactory
region: located
on roof of nasal
cavity, allowing air
to be held there so
it can be sampled

30. Respiratory Region of Nose
 Respiratory region
 Air warmed to body
temperature and
moistened in this
region inside nasal
cavity, which is lined
with mucous
membranes and richly
supplied with blood
 There are three
scroll-like bones
(turbinates) that split
incoming air into three
channels, providing
more surface area

31. Respiratory Region of Nose
 Respiratory region
 Turbinates serve to
make incoming air
current more
turbulent, bringing
more air in contact
with mucous
membranes for
warming and moisture,
adding 650 to
1,000mLs of water
each day to moisten
air to 80% relative
humidity

32. Mucociliary Elevator
 Cells in epithelial lining
of airways of respiratory
system are called
pseudostratified
ciliated columnar cells
 Consists of single layer
of tall columnlike cells
that have nuclei at
different heights, giving
appearance of two or
more layers
 Each columnar cell has
200 to 250 cilia on its
surface

33. Mucociliary Elevator
 Goblet cells and
submucosal glands are
interspersed.
 Mucus resides as two
layers:
Cilia reside in sol
layer; contains thin,
watery fluid that
allows them to beat
freely
Top layer is gel layer
that is more viscous
and sticky, trapping
small particles

34. Mucociliary Elevator
Cilia act as tiny "oars"
resting in watery sol layer
and beat 1,000 to 1,500
times per minute and
propel gel layer and its
trapped debris onward
and upward about one inch
per minute to be expelled

35. Mucociliary Elevator
 In nose, debris-laden
secretions pushed
toward front of
nasal cavity to be
expelled through nose
 Pseudostratified
ciliated columnar
epithelium propels
gel layer toward
oral cavity to be
expectorated with
cough or swallowed
into stomach

36. The Sinuses
 Skull contains air-filled
cavities called sinuses
that connect to nasal
cavity via small
passageways
 Located around nose
and sometimes
referred to as
paranasal sinuses
 Cavities help prolong
and intensify sound
produced with our
voice and helps to
lighten weight of
head

37. The Sinuses
 Three different sinuses:
Frontal, Ethmoid and
Maxillary
 Sinuses do not exist at
birth
 Develop as we grow;
facial features changes
influenced by sinuses as
we mature
 Sinuses also help to
warm and moisturize
air

38. Pharynx: Three Parts
 Pharynx, or throat, is hollow
muscular structure
beginning behind nasal
cavity, lined with epithelial
tissue
 Pharynx can be divided into
three sections
 Nasopharynx
 Oropharynx
 Laryngopharynx

39. Figure 13-7
The nasopharynx, oropharynx, and
laryngopharynx and related structures

40. First Part: Nasopharynx
 Nasopharynx is
uppermost section,
beginning behind
nasal cavity
 Section contains
lymphatic tissue
called adenoids;
passageways into
middle ear called
Eustachian tubes
 Air from nasal
cavity passes
through
nasopharynx

41. Second Part: Oropharynx
 Oropharynx is located
behind oral, or buccal,
cavity
 Conducts not only
atmospheric gas
but also food and
liquid
 Air breathed
through both nose
and mouth passes
through here, and
anything that is
swallowed

42. Second Part: Oropharynx
 Tonsils are part of lymph
system
 Palatine tonsils are
located in oropharynx,
as are lingual tonsils
located at back of
tongue
 During swallowing,
uvula and soft palate
move in posterior
and superior position
to protect nasopharynx
and nasal cavity from
entry of food or liquid;
can be overcome by
forceful laughing

43. Third Part: Laryngopharynx
 Laryngopharynx is
lowermost portion of
pharynx
 Air breathed and/or
swallowed passes
through
laryngopharynx
 Swallowed materials
pass through
esophagus to get to
stomach
 Air travels through
larynx and trachea
on its way to lungs

44. The Larynx
 Semi rigid structure
composed of cartilage
connected by
muscles and ligaments
that provide movement
of vocal cords to
control speech
 “Adam's apple”
(thyroid cartilage)
is largest of
cartilages found in
larynx

45. The Larynx and Glottis
 Cricoid cartilage
lies beneath it,
providing
structure and
support for
airways so they
do not collapse
 Glottis is
opening that
leads into
larynx and
eventually lungs

46. The Epiglottis
 Leaf-shaped flap like
fibrocartilage
 Closes over
opening to larynx
when you swallow;
opens up when
you breathe, as
part of swallowing
reflex (glottic or
sphincter
mechanism)
 Seals so food does
not enter lungs

47. Figure 13-8
The upper airway and related
infections

48. Vocal Cords as
Dividing Line
 Vocal cords act as
dividing line
between upper and
lower airways
 Lower airway
starts below
vocal cords
 Upper airway
ends at vocal
cords

49. Respiratory Diseases
Complete the Respiratory
Diseases Worksheet
Due Thursday Nov 12,
2013
Also due: Take home quiz
on Anatomy of the Heart

50. The Lower Respiratory Tract
 Resembles upside-down
tree, sometimes called
tracheobronchial tree
 From vocal cords, air
enters trachea, or
windpipe, 4½˝ long tube
lined with ciliated mucous
membrane

51. The Trachea and Esophagus
 C-shaped cartilage
found in anterior
portion of trachea
provide rigidity and
protection for exposed
airway in neck
 Esophagus lies in area
where C opens up
posteriorly; room for
esophagus to expand
when you swallow
larger chunks of food

52. Trachea and Mainstem
Bronchi
 Trachea is largest pipe;
can be thought of as
trunk of tree
 Trachea begins branching
(bifurcating) at center of
chest into left and right
mainstem bronchi
(bronchus is singular
form)

53. Trachea and Mainstem
Bronchi
 Site of bifurcation
is called carina
 Next bronchi must
branch into five
lobular bronchi;
correspond to five
lobes of lungs
carina

54. Bronchi of the Lung
 Each lung lobe further
divided into specific
segments; next
branching of bronchi
called segmental
bronchi
 At point from trachea
down to segmental
bronchi, tissue layers
of bronchi are all the
same, only smaller, as
they branch downward

55. Figure 13-10
Three Tissue layers in the bronchi
• Epithelial layer contains
mucociliary escalator
• Middle is lamina propria
layer which contains
smooth muscle,
lymph, and nerve
tracts
• Third layer is
protective and
supportive
cartilaginous layer

56. Bronchi in Lung Segments
 Branching continues to
tiny subsegmental
bronchi that branch
deep within each
lung segment
 Cartilaginous rings
become more irregular
and eventually fade
away
 Closer to gas exchange
regions, airways
simplify to make it
easier for gas molecules
to pass through

57. Bronchi Lead to Bronchioles
 Bronchioles average
1 mm in diameter
 Cilia, goblet cells,
and submucosal
glands are almost
all gone
 There is no gas
exchange yet

58. Terminal Bronchioles
Terminal bronchioles
mark border
between
conducting and
respiratory zones

59. Respiratory Bronchiole
 Next airways
beyond terminal
bronchioles are
respiratory
bronchioles,
because some gas
exchange occurs
here

60. Alveolar Ducts to Alveoli
 Alveolar ducts
originate from
respiratory
bronchioles,
 These give way
to alveoli

61. Figure 13-11
Conduction and gas exchange
structures and functions

62. Alveoli and Pulmonary Capillaries
 Alveoli are terminal air
sacs, surrounded by
numerous pulmonary
capillaries
 Together capillaries and
alveoli make up functional
unit of lung known as
alveolar capillary
membrane
 Adults have 300–600
million alveoli, with total
of 80 square meters (m2)
surface area for oxygen
molecule to diffuse across
into capillaries

63. Pulmonary Circulation
 Blood from right
heart entering
pulmonary
capillaries is
high in carbon
dioxide and low
in oxygen

64. Gas Exchange at Alveolar
Capillary Membrane
Gas exchange takes
place and pulmonary
capillary increases in
oxygen
concentration before
traveling to left
heart to be pumped
around to tissues
http://www.youtube.com/watch?v=A

65. Gas Exchange at Alveolar
Capillary Membrane
1. The pressure of oxygen in the alveolus is higher
than in the capillary and by SIMPLE DIFFUSION, the
oxygen enters the circulatory system

66. Gas Exchange at Alveolar
Capillary Membrane
2. The pressure of carbon dioxide in the capillary is
higher than in the alveolus and by SIMPLE
DIFFUSION, the CO2 enters the respiratory system
and is exhaled

67. Gas Exchange at Cellular
Membrane
3.At the tissue level, the pressure of oxygen in
the capillary is higher than in the tissue and by
SIMPLE DIFFUSION, the oxygen enters the cell.

68. Gas Exchange at Cellular
Membrane
4.The pressure of carbon dioxide in the cell is higher
than in the venule and by SIMPLE DIFFUSION, the
carbon dioxide enters the circulatory system

69. Housing of the Lungs
and Related Structures
 Lungs reside in thoracic
cavity and are separated
by region called
mediastinum, which
contains esophagus, heart,
great vessels, and trachea
 Breathing in and out
causes lungs to move
within thoracic cavity

70. Pleura of the Lungs
To prevent
irritation of lungs
moving against
thorax, each lung
wrapped in sac or
serous membrane
called visceral
pleura

71. Pleura of the Lungs
 Thoracic cavity
and upper side of
diaphragm lined
with continuation
of membrane
called parietal
pleura

72. Pleural Space with Fluid
Between these two
pleural layers is
pleural space
(intrapleural space),
which contains
slippery liquid called
pleural fluid that
reduces friction as
individual breathes

73. The Lungs
 Conical-shaped with rounded
peaks (apex) extending 1 to
2 inches above clavicle
 Base of lungs rest on right
and left hemi diaphragm with
right lung base a bit
higher to accommodate liver
Cardiac
impression
Medial surface of lung has deep, concave
cavity that holds heart, called cardiac
impression, and is deeper on left side

74. Hilum of The Lungs
Hilum is area where
root of each lung
is attached,
containing main
stem bronchus,
pulmonary artery
and vein, nerve
tracts, and lymph
vessels

75. The Lobes of the Lungs
 Right lung has three
lobes: upper, middle,
lower lobes; divided by
horizontal and oblique
fissures
 Left lung has one
fissure, oblique fissure,
and therefore has only
two lobes: upper and
lower lobes
 Lingula is area of left
lung that corresponds
with right middle lobe

76. The Lobes of the Lungs
 Left lung has only two
lobes because largest
part of heart is located
in left lung area
 Right lung is larger, with
60% of gas exchange
occurring here

77. Figure 13-15
Structures of the thoracic cavity

78. The Protective Bony Thorax
 Bony and cartilaginous
frame providing
freedom of
movement
 Protects organs of chest
 Includes rib cage,
sternum, and thoracic
vertebrae to which
each rib attaches
 Sternum, or
breastbone, is centrally
located; comprised of
manubrium, body, and
xiphoid process

79. The Protective Bony Thorax
True ribs (pairs 1–
7): called vertebro
sternal; connect to
sternum and
vertebrae
Pairs 8–10: called
false ribs or
vertebro costal;
connect to costal
cartilage of superior
rib and to thoracic
vertebrae

80. Figure 13-17
The thoracic cage

81. How We Breathe
Respiratory
control center is
in medulla
oblongata
which is part of
the brain stem
and is
continuous with
the spinal cord

82. How We Breathe
Inspiration: active
process in which
diaphragm is sent
signal via
phrenic nerve,
causing it to
contract and
flatten
downward,
increasing
thoracic cavity
space

83. How We Breathe
Increase in
thoracic cavity
volume
decreases
pressure,
creating lower
pressure in lungs
than outside,
allowing air to
rush into lungs

84. Figure 13-18
How we breathe
Ease of ventilation is called
compliance
•High compliance: little
effort required to expand
lungs
•Low compliance: more
difficult to expand lungs

85. How We Breathe
Exhalation: passive
act; diaphragm
relaxes, which
decreases amount of
space in thoracic
cavity; pressure in
lungs becomes
greater than
atmospheric
pressure; air is
pushed out of
lungs

86. How We Breathe
While we can
consciously
influence
breathing rate,
Our breathing rate
is normally
controlled by
level of carbon
dioxide in blood

87. How We Breathe
 If carbon dioxide
levels rise, it means
that not enough
CO2 is being
ventilated
 When this occurs,
chemoreceptors
in medulla
oblongata send
signals to
respiratory muscles
to increase rate
and depth of
breathing

88. Factors Affecting Breathing Rate

89. How We Breathe
 Accessory
Muscles include:
 Scalene muscles
in neck
 Sternocleido
mastoid
 Pectoralis major
 Pectoralis minor

90. Figure 13-19
The accessory muscles of
exhalation
Accessory muscles of exhalation assist in more
forceful and active exhalation by increasing
abdominal pressure

91. How We Breathe
Main accessory
muscles of exhalation
are abdominal
muscles that push up
diaphragm or the back
muscles that pull down
and compress thoracic
cage

92. Emphysema
Affects lung compliance:
Bronchioles become
damaged and wider, allowing
air into lungs, increasing
compliance but making it
much more difficult to
breathe out
Breathing then requires the
use of more accessory
muscles

93. Damage to the Lungs

94. Figure 13-14
Asthma and emphysema

95. Figure 13-20
Classes of drugs used to treat
respiratory disorders

96. GAS EXCHANGE
Complete the
GAS EXCHANGE
WORKSHEET IN CLASS
Use a RED pencil to
represent the direction of
the oxygen movement and
BLUE for the direction of
the carbon dioxide
movement