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Flashcards in Respiratory System Deck (30)
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1
Q

Conducting part of respiratory system

A

. Provides passageway for air to and from lungs
. Warms, moistens, and cleanses air
. Nasal cavities and assoc. paranasal sinuses, pharynx, larynx, trachea, bronchi, and most bronchioles
. Rigid walls to keep airway open

2
Q

Respiratory part of the respiratory system

A

. Facilitates gas exchange btw blood and air

. Respiratory bronchioles, alveolar ducts, and pulmonary alveoli

3
Q

Portions of conducting part of respiratory system

A

. Extrapulmonary portion

. Intrapulmonary portion

4
Q

Epithelium in most of conducting part of respiratory system

A

. Psuedostratified, ciliated, columnar epithelium w/ goblet cells (respiratory epithelium)
. Thick basement membrane

5
Q

Function of goblet cells in respiratory system

A

. Traps dust and potential infectious agents

6
Q

Muco-ciliary escalator

A

Mucous layer propelled toward pharynx by coordinated movement of cilia covering columnar cells

7
Q

Mucosa of conducting part of respiratory system

A

. Epithelium and lamina proprioception (CT)

8
Q

Where are lymphoid cells found in conducting part of respiratory system

A

Epithelium and CT layer

9
Q

Nasal cavity

A

. Initial portion lined w/ stratified squamous epithelium while other parts are lined w/ respiratory epithelium
. Respiratory epithelium supported by lamina propria w/ seromucous glands to moisten air and trap particles
. Lamina propria has superficial Venus plexus that warms air (reason for nosebleeds)
. Roof of nasal cavity lined w/ olfactory epithelium

10
Q

In nasal cavity, the lamina propria is fused w/ ___

A

Perichondrium/periosteum coverings cartilaginous or bony skeleton of nasal cavity

11
Q

Mucosa of nasal cavity Called ____

A

Mucoperichondrium or mucoperiostuem

12
Q

Function of olfactory mucosa and components of it

A

. Detection of smell

. Basal cells, bipolar olfactory sensory neurons, and supporting (sustentacular) cells

13
Q

Pharynx and larynx

A

. Lined w/ respiratory epithelium except in areas subject to abrasion (oropharynx, laryngopharynx, and epiglottis
. Have vocal cords
. Large masses of lymphoid tissue in lamina propria of nasopharynx forming Waldeyer’s ring

14
Q

Vocal cords

A

. Projections of mucosa into lumen of larynx

. Covered in stratified squamous epithelium

15
Q

Trachea

A

. Flexible tube of fibroelastic tissue reinforced w/ 12 C-shaped rings of hyaline cartilage
. Bands of smooth muscle (trachealis muscle) joint free ends of rings post.
. Surrounded by adventitia
. Lined by reparatory epithelium on thick basement membrane
. Lamina propria highly vascular w/ elastic fibers
. Submucosa has seromucous glands that dec. as you descend lower in trachea
. Submucosa merges w/ perichondrium that envelopes hyaline rings

16
Q

Cells types in trachea epithelial lining

A

. Columnar ciliated cells
. Goblet cells
. Basal stem cells ( on basement membrane, don’t extend to lumen)
. Brush cells (columnar cells w/ micovilli, function as chemoreceptors)
. Small granule cells (Kulchitsky cells, neuroendocrine cells that produce serotonin, calcitonin, and other hormones

17
Q

Bronchial tree

A

. Primary bronchi at Hilum
. Secondary (lobular) bronchi supply pulmonary lobe
. Tertiary (segmental) bronchi continue branching and form smaller bronchi and then bronchioles

18
Q

Primary bronchus

A

. Wall similar to trachea
. Lamina separated from submucosa by smooth muscle layer that’s more prominent in distal bronchi
. Submucosa contains fewer glands than trachea
. Cartilage forms flattened plates

19
Q

As bronchi become smaller, what occurs?

A

. Cartilage plates dec.
. Less goblet cells
. Thin lamina propria is completely encircled by spirally arranged smooth muscle
. Seromucous glands sparse

20
Q

Bronchioles

A

. Less than 1 mm in diameter
. No cartilage or submucosa glands
. Psuedostratifed epithelium dec. in height from more simple columnar to cuboidal ciliated at terminal bronchioles
. Goblet cells replaced w/ club cells
. Smallest portion is the terminal bronchiole

21
Q

Club cell

A

. Make 80% of epithelium at terminal bronchioles
. Protect bronchiolar epithelium
. Secret surfactant lipoproteins and mucins
. Detoxification of noxious substances (smooth ER)
. Secrete antimicrobial peptides and cytokines
. Replacement of other bronchiolar cell types

22
Q

Respiratory bronchioles

A

. Final branching of terminal bronchioles
. Transition point from conducting to respiratory part
. Lined by simple cuboidal ciliated epithelium w/ club cells and scattered alveoli
. Give rise to alveolar ducts that are continuous w/ alveolar sacs (several alveoli in one sac)

23
Q

Alveolus

A

. Sac-like evaginations from respiratory bronchioles, alveolar ducts and alveolar sacs
. 200-300 in each lung w/ total surface area of 75 m^2
. Wall has surface epithelium, interstitium and blood capillaries

24
Q

Type I alveolar cells (type I pneumocytes)

A

. Super thin cell that line 90-95% of alveolar surface
. Provide barrier of minimal thickness that is permeable to gases
. Jointed by desmosomes and tight junctions

25
Q

Type II alveolar cells (type II pneumocytes)

A

. Covers 5-10% of surface area but represents 60% of alveolar epithelial cells
. Cuboidal cells interspersed among type I cells
. Stem cells, can differentiate into Type I cell when they’re damaged
. Cytoplasm contains lamellar bodies (secretory granules w/ surfactant)

26
Q

Pulmonary surfactant

A

Lowers surface tension at air-fluid interface

. Reduces tendency of alveolus to collapse at end of exhalation

27
Q

Supporting tissue in respiratory portion of respiratory system

A

. Attenuated layer surrounding flood capillaries of alveolar wall
. Scatter fibroblasts, sparse ECM w/ reticular and elastic fibers
. Forms alveolar septa that separate alveoli

28
Q

Alveolar pores

A

. Openings in alveolar septa that facilitate communication and aid in equalization of air pressure btw adjacent alveoli

29
Q

Blood-air barrier

A

. Attenuated cytoplasm of type I pneumocytes
. Fused basal laminae of type I pneumocytes and of capillary endothelial cells
. Thin endothelial cells of capillary

30
Q

Alveolar macrophages

A

. Dust cells

. Bone marrow-derived lymphoid cells that present in alveolar lumen and interstitium of alveolar septum