Respiratory System Flashcards
Why is the inferior aspect of each lung curved upwards?
Because it lies on top of the domed diaphragm
True or false: the respiratory system only contains serous membranes
FALSE - it contains a mucous membrane too
What does the mucous membrane in the respiratory system line?
Conducting portion of the respiratory tract and it bears mucus-secreting cells to varying degrees
What do the serous membranes line?
Pleural sacs which envelope each lung
What can the pleural cavity fill with? (4)
- Air (pneumothorax)
- Blood (haemothorax)
- Pus (empyema)
- Watery transudate or exudate (pleural effusion)
How can fluid be drained from the pleural cavity?
By inserting a wide-bore needle through an intercostal space (now done under ultrasound guidance).
What is the danger of inserting the needle below the 7th intercostal space?
Diaphragm could be penetrated
Complete the sentence:
Intercostal nerves and vessels run in the ______ ______ along the inferior body of each rib.
Costal groove
Complete the sentence:
Cancer of the lung can cause a __________ of one side of the diaphragm if tumour impinges on the left or right _______ nerve.
Paralysis
Phrenic
What two things can cancer in the apex of the lung impinge on and what can this cause?
Brachial plexus and can cause wasting of muscles in the lower arm Sympathetic trunk (nerves), giving rise to Horner's syndrome
What are the characteristics of Horner’s syndrome? (3)
Miosis (constricted pupil) Ptosis (weak, droopy upper eyelid) Apparent anhidrosis (localised, decreased sweating)
What causes a hoarse voice in lung cancer?
Impingement on the left recurrent laryngeal nerve or aneurysm of the aorta
What constitutes as part of the conducting portion of the respiratory tract? (8)
Nasal cavity Pharynx Larynx Trachea Primary bronchi Secondary bronchi Bronchioles Terminal bronchioles
What constitutes as the respiratory portion of the respiratory tract? (3)
Respiratory bronchioles
Alveolar ducts
Alveoli
True or false: the walls of the passageways become thicker going down the order of the conducting and respiratory portions of the respiratory tract
FALSE - become thinner as their lumens decrease in diameter
Which type of epithelium lines the airways from the nasal cavity to the largest bronchioles?
Pseudostratified epithelium with cilia and goblet cells
Which type of epithelium lines the terminal bronchioles?
Simple columnar with cilia and Clara cells but no goblet cells
Which type of epithelium lines the respiratory bronchioles and alveolar ducts?
Simple cuboidal with Clara cells and few sparsely scattered cilia
Which type of epithelium lines the alveoli?
Simple squamous
What allows us to detect odours?
Olfactory mucosa
What are the two types of nasal cavities?
Non-olfactory regions
Olfactory regions
What type of epithelium is present in the non-olfactory nasal regions?
Pseudostratified ciliated epithelium
What type of epithelium is present in olfactory nasal regions?
Thick pseudostratified columnar epithelium without goblet cells
What do serous glands do and what are they called in the olfactory region?
Flush out odourants from the epithelial surface, called Bowman’s glands
Which type of epithelium are the ventricular folds of the larynx lined with?
Pseudostratified with mucous glands and numerous lymph nodules
Which type of epithelium lines the vocal cords of the larynx?
Stratified squamous
What do the vocal cords of the larynx contain? (2)
- Vocal ligament (elastic fibres)
2. Vocalis muscle (skeletal muscle)
What do the vocal cords do?
Stop foreign objects from reaching the lungs by closing to build up pressure when coughing is required
What is the difference between the trachea and the primary bronchi?
Cartilage rings and spiral muscle of primary bronchi completely encircle the lumen
What do the secretions from the epithelium and submucosal glands of the trachea and bronchi contain? (6)
Mucins Water Serum proteins Lysozyme Antiproteases Immunoglobulins
Complete the sentence:
In COPD, there is goblet cell _____________, a smaller proportion of ciliated cells and ____________ of the submucous glands
Hyperplasia
Hypertrophy
What is not present in the apical membranes of the epithelial cells of cystic fibrosis (CF) sufferers?
Cystic fibrosis transmembrane regulator (CFTR)
What happens in CF as a result of the ion channel molecule not being present?
Water doesn’t leave the epithelium in sufficient quantities to adequately hydrate mucus, mucus becomes viscous and can less readily be moved to the oropharynx for swallowing
Complete the sentence:
Absence of _________ in walls of bronchioles allows these passages to constrict and almost close down when smooth muscle contraction becomes excessive. Such __________________ can become excessive in asthma and cause more difficulty with ____________ than ___________.
Cartilage
Bronchoconstriction
Expiration
Inspiration
Why is expiration harder than inspiration for asthma patients?
During expiration, the bronchial walls are no longer held open by the surrounding alveoli
True or false: as bronchioles get smaller, goblet cells give way to Clara cells
TRUE
What do Clara cells secrete? (2)
Surfactant lipoprotein which prevents the walls sticking together during expiration
Clara cell protein (CC16)
What does CC16 protein do? (2)
Measurable marker in bronchoalveolar lavage fluid (if lowered then lung damage)
Measurable marker in serum (if raised then leakage across air-blood barrier)
Why is the absence of goblet cells in terminal bronchioles important?
To prevent individuals from ‘drowning’ in their own mucus
What can alveoli open into? (4)
- Respiratory bronchioles
- Alveolar duct
- Alveolar sac
- Another alveolus
Describe the properties of alveolar walls (4)
- Have abundant capillaries
- Supported by basketwork of elastic and reticular fibres
- Have a covering composed of type I pneumocytes
- Have scattering of intervening type II pneumocytes
What causes emphysema?
Destruction of alveolar walls and permanent enlargement of air spaces which can result from smoking or alpha1-antitrypsin deficiency
What is the hallmark sign of emphysema?
Pursed-lip breathing
What happens when alveolar walls are damaged?
Bronchioles collapse, making it difficult for lungs to empty so air becomes trapped in alveoli
What causes pneumonia?
Inflammation of the lung caused by bacteria (Streptococcus pneumoniae is most common)
