2.2: The Respiratory Tract Histology Flashcards
______ is the study of the cellular anatomy of a tissue or organ that can be viewed through a microscope.
Histology
What is Histology?
the study of the cellular anatomy of a tissue or organ that can be viewed through a microscope.
The typical ______ (or lining of the respiratory tract) is primarily made of ciliated, pseudostratified, columnar cells.
respiratory epithelium
The typical respiratory epithelium (or lining of the respiratory tract) is primarily made of what?
ciliated, pseudostratified, and columnar cells
The cells of the respiratory epithelium have ___1___ at the apex or top of the ___2___.
- small cilia (small hair-like projections)
- cells (apical side)
These cilia move or “beat” in an ___1___ motion. Their action helps to ___2___.
- upward sweeping
- keep the respiratory tract free of debris
These cells are called ______ because they appear to be in layers.
pseudostratified
Upon closer examination, all the cells of the respiratory epithelium attach to the ______ of the epithelial tissue.
basement membrane or “floor”
Cells that are taller than they are wide are called what?
columnar
columnar means what?
Cells that are taller than they are wide
Goblet cells produce what?
Mucus
What cell produces mucus?
Goblet cells
True or False: Goblet cells (mucus producing cells) are present within the epithelium of the respiratory tract.
True
Goblet cells are named for their ______.
wineglass (or goblet) like appearance
Goblet Cells’ mucus helps to ___1___ within the respiratory tract, which can then be more easily removed by the ___2___.
- trap debris
- cilia
Diagram of the typical cells of the respiratory epithelium
Respiratory Epithelium: note the small cilia at the top (apex) of these cells
______, much like skin, can be found at the entrance of the respiratory system.
Stratified squamous epithelium
Stratified means ___1___ and squamous means ___2___.
- layered
- flattened
___1___ means layered and ___2___ means flattened.
- Stratified
- squamous
True or False: Stratified squamous epithelium is only found in a singular flattened layer.
Stratified squamous epithelium is found in multiple flattened layers.
True or False: One example of Stratified squamous epithelium in the respiratory tract is found just inside the nostril (vestibule) of the nose.
True
In the smaller bronchioles, the epithelium transitions into ______.
simple squamous epithelium
Simple refers to the presence of ___1___. Simple squamous refers to ___2___.
- only one layer of cells
- a single layer of flattened cells
The structure of the simple squamous epithelium allows for ______ to occur in the respiratory bronchioles.
the exchange of gasses
The amount of goblet cells, ciliated cells, and cartilage all progressively decrease as ___1___, until all are absent at the level of the ___2___.
- bronchioles become smaller and smaller
- respiratory bronchioles
The amount of what three things progressively decrease as bronchioles become smaller and smaller, until all they are absent at the level of the respiratory bronchioles?
goblet cells
ciliated cells
cartilage
What is the primary function of the cells within the alveoli?
is to allow efficient exchange of gases between the air and blood.
A lipoprotein called ______ covers the luminal surface and keeps the alveoli from sticking together during exhalation.
surfactant
What is surfactant?
A lipoprotein that covers the luminal surface and keeps the alveoli from sticking together during exhalation.
True or False: The walls of the alveoli are constantly kept moist with mucus.
False. The walls of the alveoli are constantly kept moist with WATER.
Since water molecules are attracted to each other, the alveoli can become difficult to inflate without ______ to break up the water molecules.
surfactant
Without ______ the open, circular structure of the alveoli cannot maintain their shape, making the exchange of gases difficult or impossible.
surfactant
The lungs of premature babies often have not developed the ability to make ______.
surfactant
What is the reason many preemies have respiratory problems after birth and need to remain hospitalized until their lungs fully develop?
The lungs of premature babies often have not developed the ability to make surfactant.
Respiratory membrane with type I and type II alveolar cells and alveolar macrophages present. Note the surfactant lining the inner surface of the alveoli.
What are the three major cell types of the alveoli?
- type 1 alveolar cells
- type 2 alveolar cells
- macrophages
What are the two epithelial cell types in the alveoli?
Type I and Type II alveolar cells
Type I alveolar cells make up ___% of alveolar epithelium.
95%
______ form the very thin, simple squamous epithelium of the alveoli in junction with capillaries.
Type I alveolar
Type I alveolar form the very thin, ___1___ of the alveoli in junction with ___2___.
- simple squamous epithelium
- capillaries
___1___ cells make up 5% of alveolar epithelium and are dispersed throughout the ___2___cells.
- Type II alveolar
- Type I
One function of Type II alveolar cells is to produce and secrete pulmonary ______, which is needed throughout the alveolar surface to keep the alveoli open.
surfactant
Type II cells can ___1___ to replace damaged ___2___.
- divide
- Type I cells
Aside from Type I and Type II alveolar cells, a third type of cell found within the alveoli called ______.
alveolar macrophages (also known as dust cells)
Alveolar macrophages are also known as ______.
dust cells
True or False: Because of the small amount of interaction with the outside environment within the alveoli, alveolar macrophages are found in relatively small amounts.
False. Because of the HIGH interaction with the outside environment within the alveoli, alveolar macrophages are found in ABUNDANCE.
Which cell is the most abundant cell within the alveoli?
Alveolar macrophages
What do Alveolar macrophages phagocytize?
toxic particles
allergens
infectious material (bacteria or another pathogen)
What is the primary immune defense system of the alveoli?
Alveolar macrophages
What does an Alveolar macrophages do once it has phagocytized a particle or pathogen?
Once a macrophage has phagocytized a particle or pathogen, it migrates toward the ciliary surface of the bronchiolar system. Once on the surface, the cilia carry the macrophage and particles to the mouth to be expectorated or swallowed.
