Respiratory- Dennis

Question 1

Conducting Portion

Answer 1

Collects & warms air
• Transmits air to respiratory portion
• Nasal cavity, paranasal sinuses,
nasopharynx, trachea,
• Primary, secondary, & tertiary
bronchi
• Bronchioles, terminal bronchioles

Question 2

Respiratory portion:

Answer 2

• Passes air to alveoli with the
purpose of gaseous exchange
• Respiratory bronchioles, alveolar
ducts, alveolar sacs

Question 3

Respiratory Epithelium

Answer 3

Pseudostratified columnar ciliated
epithelium

• Lamina propria has a rich, vascular
network with a complex set of
capillary loops

• Confined to airways of the
respiratory system

Question 4

Nasal cavities divided by

Answer 4

nasal septum and has three regions:

Nasal vestibule

Respiratory region

Olfactory region

Question 5

Nasal vestibule

Answer 5

just inside the

nostrils, lined by skin

Question 6

Respiratory region

Answer 6

inferior 2/3 of
nasal cavities, lined with respiratory
mucosa

Question 7

Olfactory region

Answer 7

located at the
apex (upper 1/3), lined by
specialized olfactory mucosa

Question 8

function of nasal cavities

Answer 8

adjusts temperature &
humidity of inspired air
• Enhanced by large surface area
provided by the turbinate bones

Question 9

Olfactory Mucosa

Answer 9

• Contains receptors for sense of smell
• Pseudostratified ciliated columnar epithelium (10 cm2 area)
• Olfactory glands → serous secretions that dissolve odorant molecules

Question 10

Olfactory receptor cells

Answer 10

• Have single dendritic process
• Specialized, nonmotile cilia w/
odorant receptors
• Ligand binding causes signals to
be sent to olfactory bulb

Question 11

Basal cells

Answer 11

stem cells for olfactory receptor & supporting cells

Question 12

Brush cells

Answer 12

Ciliated, columnar epithelial cells

Question 13

Supporting/sustentacular cells

Answer 13

provide mechanical & metabolic support to

olfactory receptor cells

Question 14

Trachea

Answer 14

• Short, flexible, air tube that serves as
a conduit for air
• Extends from the larynx & divides into
the main/primary bronchi
• Lumen of the trachea remains open
because of stacked cartilaginous rings

Four layers

Question 15

Mucosa

Answer 15

composed of a ciliated,
pseudostratified epithelium and an
elastic, fiber
-rich lamina propria

Question 16

Submucosa

Answer 16

composed of a slightly
denser connective tissue than the
lamina propria

Question 17

Cartilaginous layer,

Answer 17

composed of C-shaped hyaline cartilages

Question 18

Adventitia

Answer 18

composed of connective
tissue that binds the trachea to adjacent
structures

Question 19

Terminal bronchioles

Answer 19

bring air to deepest portion

Question 20

Respiratory bronchiole branching

Answer 20

alveolar ducts to alveolar rings to alveolar sacs to alveoli

Question 21

Alveolar septum

Answer 21

wall of alveolar capillaries surrounded

by elastin & collagen fibers

Question 22

Alveolar pores

Answer 22

small openings that permit movement

of air b/w alveoli

Question 23

Alveoli

Answer 23

Blind-ended sacs lined with
pneumocytes (Type I &
Type II)

Contains simple squamous
epithelium, supporting
tissue, & blood vessels

Question 24

Type I Pneumocytes (P1)

Answer 24

Line almost the
entire alveolar
surface

Create surface for
gas exchange

Closely associated
with capillaries

Question 25

Type II Pneumocytes (P2)

Answer 25

• Rounded cells that comprise about 60% of the epithelium, but cover 5% of surface area • Secrete surfactant, reduces surface tension within alveoli, preventing collapse during respiration • Lamellar bodies rich in a mixture of phospholipids, neutral lipids, & proteins • Secreted by exocytosis as surfactant

Question 26

Goblet Cells

Answer 26

Modified columnar epithelial cells that synthesize & secrete mucus Apical cytoplasm contains a dense aggregation of mucigen granules ``` Released by exocytosis & combine with water to form viscid secretion called mucus ``` ``` The ‘stem’ of the goblet is occupied by a basal nucleus & crammed with organelles ```

Question 27

Clara cells

Answer 27

secrete a lipoprotein that prevents luminal adhesion w/ airway collapse (during expiration)

Question 28

Alveolar rings:

Answer 28

aggregates of smooth muscle, collagen & elastic fibers, that form rings around alveolar ducts

Question 29

Asthma

Answer 29

• Chronic inflammatory disease involving the airways • Recurrent obstruction of airflow due to bronchiole inflammation & smooth muscle constriction (bronchospasm) • Difficult for air to move in/out of alveoli • Wheezing, coughing, shortness of breath, & chest tightness • Infiltration of the bronchiolar wall by eosinophils, lymphocytes, & mast cells • Thick bronchiolar epithelium w/ ↑↑ goblet cells, thick basement membrane, & hyperplastic smooth muscle cells

Question 30

Emphysema

Answer 30

• Permanent enlargement of air spaces distal to terminal bronchiole • Chronic obstruction of airflow due to narrowing of bronchioles • Accompanied by destruction of the alveolar wall • A significant area for gas exchange is lost in this disease • Smoking cigarettes, chronic inhalations of particulate material (coal dust, construction dust)

Question 31

Pneumonia

Answer 31

``` • Inflammation of the lung tissue • Air spaces are filled with exudate containing WBCs (mainly neutrophils), RBCs, & fibrin • Enlarged capillaries, congested with RBCs • ‘Red hepatization stage’ • On gross examination lung appears red, firm (due to lack of air spaces), & heavy (presence of exudate) ```

Question 32

Visceral Pleura

Answer 32

``` • Covered in a flattened, mesothelium** • Underlying fibrous tissues of collagen & elastin fibers • Extend into the lung as fibrous septa, continuous with lung parenchyma • Contains extensive lymphatic vessels ```