Compendium 4. The Respiratory System Flashcards
What are the 5 functions of the respiratory system?
- Respiration (gas exchange)
- Regulation of blood pH
- Voice production
- Olfaction (smell)
- Protection against dust or microorganisms via mucous or cilia
What are the 2 divisions of the respiratory system?
- Upper respiratory tract
- Lower respiratory tract
What are the main functions of the conducting zone?
- Passage way for air
- Filters and cleans air
- Humidifies and warms air
- Olfaction
- The resonating chamber for speech
How does the nasal cavity humidify and warm the air that travels through?
- Warms via the blood flowing through the nasal capillaries
- Moistens via the mucous epithelium and excess tears that drain into the nasal cavity
What is the vestibule?
The entry into the nasal cavity (your nose holes hehe)
What is the uvula?
The dangly piece of tissue at the back of your throat
What is the septum?
The dividing piece of cartilage that separates the two nostrils
What are concha and what is their purpose?
The bony ridges in the nasal cavity
The concha increases the surface area within the nasal cavity and creates a more turbulent air flow (exposed unwanted particles to mucous so that they don’t enter the lungs)
What type of epithelium lines the vestibule?
Stratified Squamous
What type of epithelium lines the concha?
Pseudo-stratified ciliated columnar
What are the 3 regions of nasopharynx?
- Nasopharynx
- Oropharynx
- Laryngopharynx
What epithelium lines the nasopharynx?
Pseudo-stratified ciliated columnar
What epithelium lines the oropharynx?
Stratified squamous
What epithelium lines the laryngopharynx?
Stratified squamous
How many cartilage pieces make up the larynx?
9
- 6 are paired (one on either side of the larynx)
- 3 are unpaired
Name the 9 cartilage pieces
Paired
- Cuneiform
- Corniculate
- Arytenoid
Individual
- Epiglottis
- Thyroid
- Cricoid
What are the main functions of the larynx?
- Maintains an open passageway for air movement
- Directs food into the oesophagus away from the respiratory tract via the epiglottis
- Traps irritating particles from entering the lungs
How many hyaline cartilage rings does the trachea have?
15-20
What epithelium lines the tracheal lumen?
Pseudo-stratified ciliated columnar
What is the Carina?
An extremely sensitive area that is the point in which the trachea branches off into the primary bronchi.
What are the transitions of epithelium as it gets deeper into the lungs?
pseudo-stratified ciliated columnar to simple ciliated columnar to simple ciliated cuboidal
Explain the divisions of the branches in the lungs
Primary (main) bronchi Secondary (lobar) bronchi Tertiary (segmental) bronchi Bronchioles Terminal bronchioles Respiratory bronchioles Alveolar duct Alveoli
How many lobes are in the left and right lung?
Right - 3 lobes (superior, middle and inferior
Left - 2 lobes (superior and inferior)
What type of epithelium is found in the capillaries covering the alveoli?
Simple squamous
What type of epithelium is found in the alveoli?
Simple squamous
What is the hilum?
The entry of the primary bronchi, nerves and blood capillaries into the lungs
What are the 4 factors that affect gas exchange?
- The thickness of the respiratory membrane
- Surface area
- Diffusion coefficient
- Partial pressure
How is oxygen transported around the body?
- 5% in haemoglobin
1. 5% dissolved in blood plasma
How is carbon dioxide transported around the body?
70% ( as bicarbonate ions) dissolved in blood plasma
7% ( as itself) dissolved in blood plasma
23% bound to haemoglobin
What are the 5 structures involved in ventilation and how do they move?
Lungs
Inspiration - volume increases as it fills with air
Expiration - volume decreases as air leaves
Diaphragm
Inspiration - contracts inferiorly
Expiration - relaxes superiorly
Rib cage and sternum
Inspiration - elevates
Expiration - depresses
Intercostal muscles
Inspiration - contracts
Expiration - relaxes
What is Boyles Law?
Volume is inversely proportional (opposite) to pressure
What are the two pressures during respiration?
Barometric air pressure - the atmospheric air pressure outside of the body
Intra-alveolar pressure - The pressure inside the alveoli
What changes come about in the two respiratory pressures during respiration?
During inspiration, barometric is higher than intra-alveolar
During expiration, barometric is lower than intra-alveolar
What forces assist in alveoli recoil?
- Fine elastics that cover the alveoli
- The surface fluid which coats the alveoli and reduces high tension
What forces assist in lung expansion?
- Intrapleural pressure being less than intraalveolar pressure
- Visceral pleura adhering to parietal pleura via the pleaural fluid
Define tidal volume
The amount of air inspired or expired with each breath
Define inspiratory reserve volume
The amount of air that can be inspired forcefully on top of inspiration of the tidal volume
Define expiratory reserve volume
The amount of air that can be forcefully expired after expiration of the tidal volume
Define residual volume
The amount of air that remains in the lungs even after the most forceful expiration
What is inspiratory capacity?
Tidal volume plus inspiratory reserve volume
the maximum amount a person can expire after a normal respiration
What is functional residual capacity?
Expiratory reserve volume plus residual volume
The amount of air remaining in the lungs at the end of normal respiration
What is vital capacity?
Inspiratory reserve volume plus tidal volume plus expiratory reserve volume
(The maximum volume of air that can be expelled from the lungs after maximum inspiration)
What is lung capacity?
Inspiratory reserve volume plus tidal volume plus expiratory reserve volume plus residual volume
What is respiratory rate?
The number of breaths taken each minute
What is minute ventilation?
Total amount of air into and out of the respiratory system each minute (tidal volume x respiratory rate)
What is anatomic dead space?
Regions in the respiratory system where gas exchange does not take place
What is a restrictive lung disease?
When a person cannot fully expand their lungs during respiration eg emphysema
What are dynamic measurements?
Lung volume measurement in relation to time
What do dynamic measurements actually measure?
- Forced vital capacity - the maximum volume of air that can be forcefully expired fast as possible after a deep breath in.
- Forced expiratory volume in 1 second - the volume of air expired in the first second of the test
- Forced expiratory volume 1% - FEV1sec expressed as a percentage of the FVC
