Respiratory System Flashcards
Name the components in the extra-pulmonary and intra-pulmonary space
Extra-pulmonary: Nasal cavity Pharynx Larynx Trachea Primary Bronchi
Intra-pulmonary: Secondary Bronchi Bronchioles Terminal Bronchioles Respiratory Bronchioles Alveolar ducts Alveoli
What is the conducting portion of the respiratory system and what is it made of?
Conducting portion: made of mucous membrane Nasal cavity Pharynx Larynx Trachea Primary Bronchi Secondary Bronchi Bronchioles Terminal Bronchioles
What is the respiratory portion of the respiratory system and what is it made of?
Respiratory portion: made of serous membrane
Respiratory Bronchioles
Alveolar ducts
Alveoli
How does the epithelium of the respiratory system change?
Psuedostratified epithelium with cilia and goblet cells (nasal cavity - bronchioles)
Simple columnar epithelium with cilia and Clara cells (terminal bronchioles)
Simple cuboidal epithelium with cilia and Clara cells (respiratory bronchioles and alveolar ducts)
Simple squamous epithelium with type I and II pneumocytes
How else does the respiratory system change?
The number of cilia decreases
Thickness of the walls decreases
The size of the lumen decreases
The number of airways (and therefore surface area) increases
What are Clara cells and what is their specific function?
Take over goblet cells with a dome-shaped apical surface used for secreting granules for clearing mucous (airway is too narrow)
Also secrete surfactant-like lipoprotein
What are type I and II pneumocytes?
Type I pneumocytes: simple squamous epithelium where gas exchange takes place
Type II pneumocytes: Clara cells of the lungs secrete surfactant
What is the function of the non-olfactory and the olfactory regions of the nasal cavity (and how do their structures differ)?
Non-olfactory: Warms and moistens air before it reaches the airways (contains mucosal glands)
Olfactory: Detects smells with bipolar neurones and removes them with bowmans gland (contains no goblet cells and cilia are motionless)
What are the layers of the trachea?
(Oesophagus is separated from the back of the trachea by trachealis muscle - some control over patency )
C-rings of hyaline cartilage (maintains patency - open lumen - and provides strength and flexibility)
Sub-mucosa with seromucous glands
Lamina propria (with elastic fibres and immunocytes)
Mucous membrane (psuedostratified epithelium with cilia and goblet cells)
Lumen
How does the cartilage change as it moves toward the lungs?
Trachea: C-rings of cartilage
Primary Bronchi: O-rings of cartilage
Secondary Bronchi: islands of cartilage
What vessels are present in the lungs and what do they carry?
Pulmonary artery: de-oxygenated blood picking up O2
Pulmonary vein: oxygenated blood returning to left atrium
Bronchial artery: oxygenated supplying the lungs
Bronchial vein: de-oxygenated blood returning to the right atrium
Describe the composition of alveoli in the respiratory portion of the lungs?
(Terminal bronchioles: no alveolar openings)
Respiratory bronchioles: alveoli on the bronchioles wall
Alveolar ducts: alveoli ubiquitous on the duct wall
Alveolar sacs: made of alveoli
What is the relationship between bronchioles and asthma?
Bronchioles contain no cartilage or glands
When sympathetic innervation of smooth muscle becomes excessive (bronchospasm) can cause complete closure of the airways of the bronchioles
What are some of the features of the alveoli?
Abundant capillaries
Basket work of elastic (stretch and recoil) and reticular (support) fibres
Mostly type I pneumocytes with a few type II pneumocytes
What is emphysema?
Destruction of alveolar walls and permanent enlargement of air spaces
During exhalation, bronchioles walls collapse preventing air from escaping alveoli
