Nose Flashcards
The conducting portion consists of
- Nasal cavities
- Nasopharynx
- Larynx
- Trachea
- Bronchi
- Bronchioles
- Terminal bronchioles
The respiratory portion consists of:
- Respiratory bronchioles
- Alveolar ducts
- Alveoli
The conducting portion serves two main functions:
- To provide a conduit through which air moves to and from the lungs
- To condition the inspired air.
Most of the conducting portion is lined with:
ciliated pseudostratified
columnar epithelium known as respiratory epithelium
Respiratory epithelium has at least five cell types:
- Ciliated columnar cells
- Goblet cells
- Brush cells
- Small granule cells
- Basal cells
Respiratory epithelium ciliated columnar cells are
the most abundant, each with about 300 cilia on its apical surface
Respiratory epithelium Goblet cells are
- Abundant in some areas of the respiratory epithelium
- Filled in their apical portions with granules of mucin glycoproteins.
Identify Goblet Cells
Respiratory epithelium Brush cells
- Brush cells express some signal transduction components like those of gustatory cells
- Have afferent nerve endings on their basal surfaces and are considered to be chemosensory receptors.
- Are a much more sparsely scattered and less easily found
- Columnar cell type, which has a small apical surface bearing a tuft of many short, blunt microvilli
Respiratory epithelium Small granule cells
- Are also difficult to distinguish in routine preparations
- Possess numerous dense core granules 100–300nm in diameter.
- Like brush cells, they represent about 3% of the total cells
- Are part of the diffuse neuroendocrine system
Respiratory epithelium Basal cells
- Small rounded cells on the basement membrane
- Not extending to the luminal surface
- Are stem cells that give rise to the other cell types.
Immotile cilia syndrome causes:
- Infertility in men
- Chronic respiratory tract infections in both sexes
Immotile cilia syndrome is caused by :
- Immobility of cilia and flagella induced
- In some cases by a deficiency of dynein, a protein normally present in the cilia.Dynein participates in the ciliary movement
The left and right nasal cavity each has two components:
- The external vestibule
- The internal nasal cavities (or fossae).
The vestibule is the most
anterior and dilated portion of each nasal cavity.
Within the vestibule, the epithelium
- Loses its keratinized nature
- Undergoes a transition into typical respiratory epithelium before entering the nasal fossae.
Skin of the nose enters the
nares (nostrils) partway up the vestibule
Embedded in the epithelial lining of the external vestibule are hairs called:
Vibrissae
Whiskers or vibrissae (singular: vibrissa) are
a type of mammalian hair that are typically characterised, anatomically, by their large size, large and well-innervated hair follicle and by having an identifiable representation in the somatosensory cortex of the brain
Where does epithelium loses its keratinized nature and undergoes a transition into typical respiratory epithelium
Within the vestibule,
The nasal cavities lie within the skull as
Two cavernous chambers
The nasal cavities are separated by
The osseous nasal septum.