Download Chapter 24 - respiratory

Chapter 24
Respiratory system
Black carbon deposits seen in the large
holes. The alveoli that used to occupy
those spaces have broken down,
creating large, rather than small sacs.
• I. Functions
•
A. Functions:
•
1. Allows oxygen from air to enter
blood & carbon dioxide in blood to leave
body in exhaled air.
•
- Inspiration & Expiration
•
2. help maintain proper acid-base
balance of blood –CO2 in blood = carbonic
acid
•
3. produces vocal sounds through
phonation
• B. Divisions
•
1. Upper respiratory system: Nose,
paranasal sinuses, pharynx, nasal cavity.
•
“condition the air”: humidify, warm, filter
(nose hairs, mucus). Protect lower
respiratory systems
from debris, pathogens & temp.
extremes.
•
2. Lower respiratory system: larynx,
trachea, bronchi, lungs
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II. Upper Respiratory System
A. Nasal cavity
1. superior, middle, inferior nasal conchae: for air turbulence
& increase surface area for warming &
humidifying.
2. superior, middle, inferior meatus: spaces between
conchae
3. nasal septum (made from ethmoid & vomer bones)
4. eustacian tube opening
B. Paranasal sinuses
1. Frontal sinuses(2), sphenoid air cells, ethmoid air cells,
maxillary sinuses(2)
2. Reduce weight of skull, help voice resonate
C. Epithelium
1. Stratified squamous near nares.
2. ciliated pesudostratified columnar with goblet cells
(respiratory epithelium)
3. olfactory epithelium
Figure 24.1 Structures of the Respiratory System
Frontal sinus
Nasal cavity
Nasal conchae
Nose
Sphenoidal sinus
Internal nares
Tongue
Nasopharynx
UPPER
RESPIRATORY
SYSTEM
LOWER
RESPIRATORY
SYSTEM
Hyoid bone
Larynx
Esophagus
Trachea
Bronchus
Clavicle
Bronchioles
RIGHT
LUNG
Ribs
LEFT
LUNG
Diaphragm
Figure 24.4a Respiratory Structures in the Head and Neck, Part II
Frontal sinus
Nasal cavity
Superior
Middle
Internal nares
Inferior
Nasal
conchae
Nasopharynx
Nasal vestibule
Pharyngeal tonsil
External nares
Entrance to auditory tube
Hard palate
Soft palate
Palatine tonsil
Oral cavity
Oropharynx
Tongue
Epiglottis
Mandible
Aryepiglottic
fold
Lingual tonsil
Hyoid bone
Laryngopharynx
Thyroid cartilage
Glottis
Cricoid cartilage
Vocal fold
Trachea
Esophagus
Thyroid gland
A sagittal section of the head and neck
© 2012 Pearson Education, Inc.
Figure 24.4b Respiratory Structures in the Head and Neck, Part II
Ethmoidal
air cell
Medial rectus
muscle
Cranial cavity
Frontal sinus
Right eye
Lens
Lateral rectus
muscle
Superior
nasal concha
Superior
meatus
Middle nasal
concha
Nasal
septum
Perpendicular
plate of
ethmoid
Vomer
Hard palate
Middle meatus
Maxillary sinus
Inferior nasal
concha
Inferior meatus
Tongue
Mandible
A coronal (frontal) section of the head showing the
positions of the paranasal sinuses and nasal structures
Figure 24.2a Histology of the Respiratory Epithelium
Movement
of mucus
to pharynx
Ciliated columnar
epithelial cell
Mucous cell
Stem cell
Mucous layer
Lamina propria
Diagrammatic view of the
respiratory epithelium
III. Lower Respiratory Tract
A. Larynx
- Superiorly, attaches to hyoid bone. Inferiorly it is
continuous with the trachea.
1. Epiglottis- elastic cartilage
2. 9 cartilages support the larynx & vocal cords.
1. Thyroid cartilage (2)- large, 2 cartilage
plates.
Laryngeal prominence
2. Cricoid cartilage- only cartilage forms a
complete ring.
3. Arytenoid cartilage (2) anchor the vocal
cords
4. Corniculate cartilage (2)
5. Cuneiform cartilage (2)
3. Ligaments & Membranes
1. Thyrohyoid ligament
2. Thyroid membrane
3. Cricothyroid ligament
4. Cricotracheal ligament
Figure 24.5 Respiratory Structures in the Head and Neck, Part III (Part 1 of 1)
Inferior nasal
concha
Hard palate
Arbor vitae of cerebellum
Choroid plexus
Soft palate
Foramen magnum
External occipital crest
Dens
of
axis
(C2)
Atlas (C1) (posterior arch)
C3
Laryngopharynx
Tongue
Nasopharynx
Uvula
Atlas (C1)
(anterior arch)
Oropharynx
Mandible
Epiglottis
C4
Spinal cord
Hyoid bone
C5
Ventricular fold
C6
Spinous processes
of vertebrae
C7
Vocal fold
Thyroid cartilage
Cricoid cartilage
T1
Tracheal cartilages
Esophagus
T2
Trachea
T3
External jugular vein
Right common
carotid artery
Manubrium of sternum
Aortic arch
Pleural cavity
Left brachiocephalic vein
Body of sternum
B. Vocal Cords
1. Vestibular ligament (false vocal cord) – superior
play no part in producing sound.
2. Vocal ligament (true vocal cord)- inferior
- Between thyroid cartilage & arytenoid
cartilages. Ligament that is covered with mucosal folds.
This mucosa is avascular: appear pearly white.
Sound production, pitch, Glottis space btwn true vocal
cords
Figure 24.6a Anatomy of the Larynx
Epiglottis
Lesser cornu
Hyoid bone
Thyrohyoid ligament
(extrinsic)
Thyroid
cartilage
Larynx
Laryngeal
prominence
Cricothyroid ligament
(intrinsic)
Cricoid cartilage
Cricotracheal ligament
(extrinsic)
Trachea
Tracheal cartilages
Anterior view of the intact larynx
© 2012 Pearson Education, Inc.
Figure 24.6d Anatomy of the Larynx
Hyoid bone
Thyrohyoid
membrane
Epiglottis
Thyroid cartilage
Vestibular ligament (false vocal cord)
Corniculate cartilage
Arytenoid cartilage
Vocal
ligament (true vocal cord)
Cricothyroid ligament
Cricoid cartilage
Cricotracheal ligament
Tracheal cartilages
ANTERIOR
POSTERIOR
Sagittal section of the intact larynx
Figure 24.7ab The Vocal Cords
Corniculate
cartilage
POSTERIOR
Corniculate cartilage
Glottis (closed)
Cuneiform
cartilage
Glottis (open)
Aryepiglottic
fold
Vestibular
fold
Vocal fold
Vocal fold
Vestibular fold
Epiglottis
Epiglottis
Root of tongue
ANTERIOR
Glottis in the open
position
See vocal cords in action!- endoscope
NatGeographic- Aerosmith
Glottis in the closed
position
Figure 24.7c The Vocal Cords
POSTERIOR
Corniculate cartilage
Glottis (open)
Cuneiform cartilage
in aryepiglottic fold
Vocal fold
Vestibular fold
Epiglottis
Root of tongue
ANTERIOR
This photograph is a representative
laryngoscopic view. For this view the
camera is positioned within the
oropharynx, just superior to the larynx.
Trachea “windpipe”
• D. Trachea
• Connects the larynx to primary bronchi.
• 16-20 C-shaped hyaline cartilage rings. Open
part of C faces the esophagus so you can
swallow food.
• Lined with respiratory epithelium
• Carina: split of trachea
Figure 24.9a Anatomy of the Trachea and Primary Bronchi
Hyoid
bone
Larynx
Annular
ligaments
Trachea
Tracheal
cartilages
Location of carina
(internal ridge)
Root of
right lung
Root of
left lung
Superior
lobar bronchus
Lung
tissue
Primary
bronchi
Superior
lobar bronchus
Secondary
bronchi
Middle lobar
bronchus
Inferior
lobar bronchi
RIGHT LUNG
LEFT LUNG
Anterior view showing the plane of section for part (b)
Lower Respiratory tract- Bronchial Tree
C. Epithelium
Inferior to the vocal
cords: ciliated pseudostratified
columnar with goblet cells =
“respiratory epithelium”
Mucociliary escalator
Figure 24.9b Anatomy of the Trachea and Primary Bronchi
Esophagus
Trachealis
muscle
Lumen of
trachea
Thyroid
gland
Respiratory
epithelium
Tracheal
cartilage
The trachea
Histological cross-sectional view of the trachea
showing its relationship to surrounding structures
LM  3
E. Bronchial Tree
1. Left and right primary (main) bronchi : which lead to left and right lungs.
Right side is shorter & straighter, so an accidentally inhaled object will probably
go into right lung.
2. Secondary bronchi (lobar) – goes into each lobe. Right lung: superior, middle, inferior lobar brochi.
Left lung : only superior and inferior lobar bronchi.
3. Tertiary bronchi (segmental)
- smooth muscle around smaller bronchi & bronchioles. *asthma is due to
constriction of these smooth muscles & causes airway to become smaller.
3. bronchioles (Less than 1mm) in diameter
- cartilaginous rings gone. Have elastin
- Neither cilia nor mucus secreting cells are in the bronchioles. Any debris that are not
trapped in mucus above the level of bronchioles must be removed by macrophages.
4. terminal bronchioles (less than 0.5mm)
5. respiratory bronchioles – have alveoli
6. Alveolar sacs with alveoli
a) Alveoli are made of very thin simple squamous cells called Type I cells (0.5 µm- 15
times thinner than a sheet of tissue paper)
b) Alveolar sac is surrounded by capillaries. gas exchange. “Respiratory epithelium”
c) Type II cells: create surfactant: film of lipoprotein that lowers surface tension inside
alveoli
d) Resident macrophages
* pneumonia - when the alveoli fill with fluid & gas exchange is compromised. Very
dangerous condition.
Figure
24.13a
Trachea
Left
primary
bronchus
Secondary
bronchus
Tertiary
bronchi
Smaller
bronchi
Bronchioles
Terminal bronchiole
Respiratory bronchiole
Alveoli in a
pulmonary
lobule
-Have alveolus
The structure of one portion of a single pulmonary lobule
Alveolar ducts & sacs
• We have about 300 million alveoli within the lungs!
Surface area for gas exchange is approx. 1500 ft2.
• Alveolar sac= bunch of grapes; alveoli: one grape
Figure 24.13c Bronchi and Bronchioles
Alveolus
Alveolar
sac
Hyaline
cartilage
plate
Bronchiole
Smooth
muscle
Arteriole
Epithelial
cells
Alveolar
duct
Lumen of
a small
bronchus
Histology of the lung
LM  14
Histological section of the lung showing a small bronchus and bronchiole
IV. Pleura
1. Each lung is enclosed by this
double serous membrane.
Parietal pleura &
Visceral pleura
2. Pleural cavity:
Space between
membranes filled with pleural fluid
Pleura
V. Lungs
1. External Structures:
Apex: just deep to clavicle, pointed superior
end.
Base: concave end that contacts the
diaphragm
Costal surface: all surfaces that contact the
ribs (anterior, lateral & posterior surfaces)
Hilum: it is the indentation where blood
vessels/bronchi come in & exit lung
2. Right lung 3 lobes
superior middle & inferior
3. Left lung 2 lobes
superior & inferior
Figure 24.10a Superficial Anatomy of the Lungs
Boundary between
right and left
pleural cavities
Superior lobe
LEFT LUNG
RIGHT LUNG
Superior lobe
Oblique fissure
Horizontal fissure
Middle lobe
Fibrous layer
of pericardium
Oblique fissure
Inferior lobe
Inferior lobe
Anterior view of the opened chest,
showing the relative positions of
the left and right lungs and heart.
Falciform ligament
Liver,
right lobe
Liver,
left lobe
Cut edge of
diaphragm
Figure 24.10b Superficial Anatomy of the Lungs
Lateral Surfaces
Diagrammatic views of
the lateral surfaces of
the isolated right and
left lungs
Apex
Apex
Superior
lobe
Superior lobe
Horizontal
fissure
Middle
lobe
Cardiac
notch
Inferior
lobe
Oblique
fissure
Base
RIGHT LUNG
Oblique
fissure
Inferior
lobe
Base
LEFT LUNG
Disorders of respiratory system
Normal
Emphysema
Clinical Note 24.1 Chronic Obstructive Pulmonary Disease (COPD) (Part 2 of 3)
VI. Muscles of Respiration
A. Primary Respiratiory Muscles
1. Diaphragm
2. External intercostals (inhalation- elevate all ribs)
B. Accessory Respiration Muscles
Inhalation
1. sternocleidomastoid (lift sternum)
2. scalenes (lift first 2 ribs)
3. pectoralis minor (lift ribs 2-5)
4. serratus anterior (lifts ribs)
Exhalation
1. Tranversus abdominis (compress abdomen)
2. internal intercostals (depress ribs)
3. rectus abdominis & obliques (compress
abdomen)
VI. Disorders
A. Emphysema: chronic & incurable disorder
Alveoli walls are damaged & distended.
Surface area for gas exchange reduced. Less oxygen
reaches heart & brain- heart works overtime to pump blood
to these areas.
B. Asthma: affects bronchi & bronchioles.
Smooth muscles around bronchi &
bronchioles undergo spasms when introduced to an irritant
(allergen, cold air, smoke etc) Wheezing, breathlessness &
cough.
Treatment: Asthma can be treated with “inhalers” which
contain bronchial dilators. For chronic asthma,
corticosteroids may be given to suppress immune to
suppress allergic response