Histology of the respiratory system 1 Flashcards
What is the function of the respiratory system?
To provide O2 and to remove CO2 from the blood
Name the two divisions of the respiratory system.
- Conducting airways
- Respiratory airways
What is the function of the conducting airways? (4)
warming, humidifying, cleaning and delivering air
What is the function of the respiratory airways?
gas exchange
List the elements of the conducting airways (7)
Nasal cavity
Nasopharynx
Oropharynx
Larynx
Trachea
Bronchi
Bronchioles (regular and terminal)
List the elements of the respiratory airways (4)
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli
What are the 4 basic tissues that make up (almost) every organ?
Epithelial tissue
Connective tissue
Muscular tissue
Nervous tissue
The conducting airways possess structures that ensure…
uninterrupted supply of air (bone, cartilage, smooth muscle and connective tissue which provide rigidity, flexibility and extensibility)
What structures in the conducting airways help remove foreign particles?
Serous glands
Mucous glands
Ciliated cells
Which structures allow breathing (form a ventilation mechanism)?
Thoracic cavity
Intercostal muscles
Diaphragm
Elastic properties of the lungs
Is the pressure between the parietal and visceral pleura
a) positive
b) negative
b) negative
Trachea is composed of 16-20 rings of…
hyaline cartilage (attached by dense fibroelastic connective tissue)
Name the first layer of the tracheal wall adjacent to the lumen and its two subcomponents
Mucosa:
1. pseudostratified columnar ciliated epithelium (respiratory epithelium)
2. lamina propria
Describe in detail the two layers of the mucosa in the trachea.
Pseudostratified columnar ciliated epithelium
* Columnar ciliated cells
* Goblet cells
Lamina propria
* Loose connective tissue
* Rich in elastic fibers
* Rich network of blood vessels (help bring nutrients to the trachea and warm the air, esp. in the winter)
After the mucosa, the next layer of the wall of the trachea is…
Name its 4 components
Submucosa
- Denser irregular connective tissue
* rich in elastic fibres - Hyaline cartilage
* 16-20 C-rings of hyaline cartilage embedded in submucosa
* fibroelastic connective tissue between the C-rings - Smooth muscle cells
- Serous and mucous glands
* these glands open into the lumen of the trachea
Cartilage is mainly composed of…
collagen fibers and cells called chondrocytes (secrete ECM, including collagen)
Cartilage and smooth muscle of the conducting airways are considered a part of the…
submucosa
What is the 3rd and outermost layer of the wall of the trachea?
Adventitia: dense irregular layer of CT
Connects the trachea to adjacent organs in the mediastinum.
Specify the type of epithelium that makes up the mucosa of the trachea
Pseudostratified columnar ciliated epithelium with goblet cells
Do not confuse cilia with microvilli! Describe each of the cellular projections.
Cilia:
* Hair-like projections found on the surface of certain epithelial cells
* Move in a coordinated, wave-like manner to move fluid, mucus and particles
* Composed of microtubules
Microvilli:
* Tiny, finger like projections on the surface of certain cells
* Primarily designed to increased the surface area for absorption
* Composed of actin filaments
What is the name of the smooth muscle in the trachea?
Trachealis muscle
Name all the cell types found in pseudostratified columnar ciliated epithelium (respiratory epithelium) (6)
- Columnar ciliated epithelial cells
- Goblet cells
- Brush cells
- Basal cells
- Small granule cells
- Serous cells
The most abundant cell type in the respiratory epithelium (pseudostratified columnar ciliated epithelium) are..
ciliated columnar cells
How many cilia does each columnar ciliated cell have on its luminal aspect?
~300 cilia