Respiratory System Flashcards
1
Q
Conducting
vs
Respiratory Zone
A
- Conducting Zone
- Vestibule → Terminal bronchioles
- Warms and humidifies air
- Traps particles
- Produces sound
- Sense of smell
- Respiratory Zone
- Respiratory bronchioles → alveoli
- Gas exchange
2
Q
Nasal Cavity
Structure
A
- Nares ⇒ opening
- Vestibule ⇒ anterior most part
- Vibrissae ⇒ short thick hairs
- Conchae ⇒ shelf-like projections off septum
- Epithelia:
- Mostly lined with respiratory epithelium
- Transitional area ⇒ vestibule to respiratory region ⇒ minimally keritinized stratified squamous
-
Olfactory epithelium
- roof of nasal cavity
- nasal septum
- superior nasal concha
- Thin lamina propria
- Numerous mucous glands
- Highly vascularized
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/859/354/a_image_thumb.jpg?1518541341)
3
Q
Olfactory Epithelium
A
- Pseudostratified columnar epithelium without goblet cells
- Taller than respiratory epithelium surrounding it
- 4 cell types:
- Olfactory receptor cells
- Sustentacular cells
-
Brush cells
- Likely sensory function
- Same as those found in respiratory epithelium
-
Basal cells
- Stem cells
- Lamina propria contains olfactory nerve bundles → cribriform plate of ethmoid → olfactory nerve
-
Bowman’s glands
- Serous secretions
- Travels through ducts to surface
- Immunoglobulins provide protection
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/891/731/a_image_thumb.jpg?1518541760)
4
Q
Olfactory Receptor Cells
A
- Bipolar neurons
- Short apical dendritic processes bulges into an olfactory vesicle
-
Non-motile cilia
- First 20% of each cilia with normal 9+2 microtubule arrangement
- Rest contains 11 single microtubules
- Basal end forms axons which travel into lamina propria
- Join to form nerve bundles → olfactory nerve
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/941/510/a_image_thumb.jpg?1518542255)
5
Q
Sustentactular Cells
A
- Numerous microvilli on apical surfaces
- Apical nuclei
- Contain lipofuscin granules
- Physical support to olfactory cells
- Secrete odorant-binding proteins (OBP)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/941/797/a_image_thumb.jpg?1518542384)
6
Q
Olfaction
A
- Odorants bind to OBP in mucous
- Delivered to receptors on cilia of olfactory receptor cells
- Activates G-protein coupled receptors
- Odorants-OBP bind to various receptors with varying affinities
- Pattern sensed as particular smells
7
Q
Paranasal Sinuses
A
Frontal, ethmiodal, sphenoid, and maxilla.
- Hollows in bone surrounding nasal cavities
- Opens into nasal cavities
- Lined with respiratory epithelium
- Functions:
- resonance
- strengthening skull without additional weight
- crumple zone
- warm and humidify air
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/942/692/a_image_thumb.jpg?1518542619)
8
Q
Respiratory Epithelium
A
- Pseudostratified ciliated columnar epithelium containing goblet cells
- Found in:
- nasal cavities
- paranasal sinuses
- trachea
- bronchi
- larger bronchioles
- Contains 5 cell types:
-
Ciliated cells
- Mucociliary escalator
-
Goblet cells
- Produce mucous which coats epithelium
-
Brush cells
- Likely sensory function
- Short microvilli
-
DNES cells
- Endocrine cells secreting to lamina propria
- Catecholamines, calcitonin, gastin releasing peptide
- Do not reach epithelial surface
- Endocrine cells secreting to lamina propria
-
Basal cells
- Stem cells
-
Ciliated cells
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/942/897/a_image_thumb.jpg?1518542909)
9
Q
Pharynx
A
- Three regions:
-
Nasal pharynx
- Mostly respiratory epithelium
- May be areas of olfactory epithelium
-
Oral pharynx
- minimally keratinized stratified squamous
-
Laryngeal pharynx
- minimally keratinized stratified squamous
-
Nasal pharynx
- Passageway for air, liquid, and food
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/945/025/a_image_thumb.jpg?1518543237)
10
Q
Larynx
A
- Formed of elastic cartilage
- Connected by fibroelastic ligaments
- Moved by intrinsic and extrinsic skeletal muscles
-
Functions to:
- seperate air from liquids/solids
- control aspects of breathing
- phonation
- Most lined with respiratory epithelium
- Except epiglottis and vocal folds covered with minimally keratinized stratified squamous
- Pharynx → Epiglottis → Larynx [Vestibule → Vestibular folds → Ventricle → Vocal folds] → Trachea
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/946/378/a_image_thumb.jpg?1518544040)
11
Q
Vestibular Folds
A
a.k.a. false vocal folds
-
Structure:
- Respiratory epithelium over thick lamina propria
- Contain mucoserous glands
- Superior area → vestibule
- Inferior area → ventricle
- Seperates vestibular folds from vocal folds which lie below them
-
Functions:
- Are not involved in sound production
- Affects resonance
- Role in controlling breathing
- Helps keep liquids/solids out of airway
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/947/770/a_image_thumb.jpg?1518544494)
12
Q
Vocal Folds
A
-
Structure:
- Lie on either side of airway in anterior-posterior orientation
- Seperated by a space called the glottis
- Minimally keratinized stratified squamous
-
Fibroelastic vocal ligament
- Located within the edge of the vocal fold
-
Vocalis muscle
- Fills in the bulk of the vocal fold
- Intrinsic muscles
-
Function:
- Involved in phonation
- Vocal folds vibrate as air forced through
- Intrinsic muscles alter vocal fold tension & glottis shape → controls pitch
- Vocal ligament and vocalis muscle also involved in sound production
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/946/996/a_image_thumb.jpg?1518544810)
13
Q
Trachea
A
- Runs inferior to larynx → hila of lungs
- Divides into right ahd left primary bronchi
-
Four layers:
-
Mucosa
-
Respiratory epithelium
- Mucociliary escalator
- Thick basement membrane
-
Lamina propria
- Cellular loose CT
- Rich in elastic fibers
- Contains lymphocytes
-
Respiratory epithelium
-
Submucosa
- Seperated from lamina propria by the elastic membrane
- Denser region of elastic fibers
- Similar in makeup to lamina propria
- Contains mucoserous submucosal glands
- secrete mucous into lumen
- Contains lymphocytes which can be aggregated into nodules
- Seperated from lamina propria by the elastic membrane
-
Cartilage layer
- Contains C-rings
-
Adventitia
- Outermost layer
- Due to location within mediastinum, is not covered with mesothelium
-
Mucosa
- 16-20 C-shaped hyaline cartilages
- Cartilages interconnected to each other by fibroelastic CT
- Open ends of each C connected by trachealis muscle (smooth muscle) & fibroelastic CT
- Structure allows posteriorly located esophagus to expand into trachea during swallowing
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/948/520/a_image_thumb.jpg?1518545664)
14
Q
Bronchi
A
-
Primary bronchi
- Tracheal bifurcation → hilum of lungs
- aka left and right bronchi
- Cartilages form rings
-
Intrapulmonary bronchi
- Secondary bronchi and smaller
- Cartilage forms irregular plates
- Size decreases with each generation
- 11 generations until cartilages disappear → bronchioles
-
Five layers in bronchi:
-
Mucosa
-
Respiratory epithelium
- Height of cells decreases as bronchi becomes smaller
-
Basement membrane
- Becomes thinner
- Is no longer easily visible by LM at level of secondary bronchi
-
Lamina propria
- Loose cellular CT with lymphocytes
-
Respiratory epithelium
-
Muscularis
- Smooth muscle layer between the lamina propria and submucosa
- Only in the intrapulmonary bronchi
- Forms complete ring in larger bronchi
- Becomes sparse in smaller tubes
-
Submucosa
- Submucosal glands becomes sparse then dissappear in smaller bronchi
- Contains lymphocytes which can be aggreated into nodules
-
Cartilage layer
- Plates arranged into cylindrical tube shape
- Adventitia
-
Mucosa
https://www.proteinatlas.org/learn/dictionary/normal/bronchus+1
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/956/105/a_image_thumb.jpg?1518547060)
15
Q
Bronchioles
A
- Start at the 12th generation after cartilage disappears
-
Respiratory epithelium in larger bronchioles
- Goblet cells present only in largest bronchioles
- Transitions to bronchiolar epithelium as height decreases
- Ciliated simple columnar
- Contains Club cells (Clara cells)
- Embedded in lung parenchyma
- Diameter controlled by state of lung expansion
-
Terminal bronchioles
- smallest duct of the conducting zone
- bronchiolar epithelium
-
Respiratory bronchioles
- start of the respiratory zone
- 3 generations with increasing ability for gas exchange
- lined in part by bronchiolar epithelium and in part by alveolar epithelium
- alveoli found at invertals which become more frequent with each generation
![](https://s3.amazonaws.com/brainscape-prod/system/cm/231/963/401/a_image_thumb.jpg?1518549556)