Respiratory System Flashcards
What two membranes are present in the respiratory system?
A Mucous membrane which lines the conducting portion of the respiratory tract.
Serous membranes which line the pleural sacs which envelope each lung
What are the names of the two pleural layers surrounding the lungs?
Visceral (nearer to lungs) and Parietal (further from lungs)
What is the pleural cavity?
The space between the visceral and parietal layers
What is a pneumothorax?
Air in the space between the layers
What is a haemothorax?
Blood in the space between the two pleural layers
What is an empyema?
Pus in the space between the two pleural layers
What is a pleural effusion?
A watery transudate or exudate in the pleural space
Where is a needle usually inserted to drain fluid from the pleural cavity?
The 7th intercostal space posteriorly
What can cancer in the apex of the lung lead to?
Impingement on the brachial plexus causing wasting of the muscles of the lower arm
What is Horner’s syndrome?
Caused by impingement on nerves in the sympathetic trunk
Miosis (constricted pupil)
Ptosis (weak, droopy upper eyelid)
Apparent anhidrosis (localised decreased swelling)
What can impingement on the left recurrent laryngeal nerve cause?
A hoarse voice
What is the conducting portion of the respiratory tract?
The nasal cavity to bronchioles
Nasal cavity, pharynx, larynx, trachea, primary + secondary bronchi, bronchioles and terminal bronchioles
What is the respiratory portion of the respiratory tract?
The respiratory bronchioles to alveoli
Alveolar ducts
What lines the airways from the nasal cavity to the largest bronchioles?
Pseudostratified epithelium with cilia and goblet cells
What lines the terminal bronchioles?
Simple columnar epithelium with cilia and Clara cells.
What lines the respiratory bronchioles and alveolar ducts?
Simple cuboidal epithelium with Clara cells and sparse cilia
What lines the alveoli?
Simple squamous and septal cells
What are the two regions of the nasal cavities?
Non-olfactory regions and Olfactory regions
Structural characteristics of the Olfactory region:
Pseudostratified epithelium
No mucus secreting goblet cells
Cilia non-motile
Olfactory cells (bipolar neurons)
The lamina propria blends with submucosa containing bowmans glands
What are the ventricular folds of the larynx lined by?
Pseudostratified epithelium containing mucous glands and lymph nodes.
What makes up each vocal cord?
A vocal ligament (large bundle of elastic fibres)
A vocalis muscle (bundle of skeletal muscle)
What shape is the cartilage in the trachea?
C shaped
What shape are the cartilage rings in the primary bronchi?
Circular
What appears histologically in COPD?
Goblet cell hyperplasia
Smaller proportion of ciliates cells
Hypertrophy of submucous glands
(More mucus and fewer cilia)
What occurs in cystic fibrosis?
The CFTR ion channel is not present in the apical membranes of epithelial cells.
Chloride ion transport across the membrane is compromised.
Water does not leave he resp tract to hydrate the mucus.
Mucus becomes more viscous, infection often happens
What prevents bronchiolar walls to stick during expiration?
A surfactant lipoprotein secreted by Clara cells
Alveoli can open into:
A respiratory bronchiole
An alveolar duct
An alveolar sac
Another alveolus (via an alveolar pore)
Characteristics of alveolar walls:
Have abundant capillaries
Are supported by a basketwork of elastic and reticular fibres
Have a covering composed chiefly of type I pneumocytes
Have a scattering of intervening type II pneumocytes
What cells cover most of the surface area of alveoli?
Squamous cells (90%)
Other 10% is cuboidal surfactant secreting
Characteristics of emphysema:
Destruction of alveolar walls and permanent enlargement of air spaces.
Bronchioles collapse making it difficult for lungs to empty.
Air becomes trapped in the alveoli.
Purses lipped breathing is a hallmark
Characteristics of pneumonia:
Inflammation of the lung caused by bacteria.
The lung consolidates as the alveoli fill with inflammatory cells.
Most common is streptococcus pneumoniae
