Respiratory Physiology Flashcards
Respiratory functions
- Provide extensive surface area for gas exchange
2. Move air to and from external surface of lung
Non respiratory functions
- Immunity- protect respiratory surface from dehydration, temperature changes and pathogens
- Participates in olfactory function (detect odour)
- Regulation of ph
- Produce sound (phonation)
- Converting angiotensin 1 to angiotensin 2 ( to regulate BP)
- Metabolic function ( production of surfactant, prostaglandins and anti thrombosis products).
- Blood reservoir (when blood vessels of lung stretch they increase blood volume up to a litre)
What is external respiration
- Inhalation of air (pulmonary ventilation)
- Exchanging of gases at alveolar
- Movement of CO2 out of body
Internal exchange
Oxygen is taken up by heamoglobin transported via blood vessels to metabolising tissue the tissues in turn release carbon dioxide which is taken up by the blood vessels to lung
Upper respiratory system
Structures above larynx
Lower respiratory system
Below larynx including larynx
Function of upper respiratory system
Warm air to 37 celcius
100 % humidity incoming air and cools air moving out
Filter any pathogens
Functions of lower respiratory tract
- Exchange of gas * type 1 alveolar cells take up the large surface are for gas exchange up to 1x10^5 m2
* increase number of pulmonary capillaries with an exchange distance of 1um
2 Protection
- alveolar macrophages - for scavenging and eradication
- surfactant produced by type 2 alveolar cells
- Vocalisation
* larynx
What are other structures involved in respiratory system
- Skeletal and musculature
- Pleural membranes
- Neural pathways play an important role inthe regulation of Resp system
Function of bones, muscles and membranes
•they creator and transmit a pressure gradient, relying on:
- The attachment of the muscles to the ribs
- The attachment of chaphragm to the lungs
- The cohesion of tre panetalpleural membrane to the visceral pleural membrane
- Expansion and recoil of the lungs
What are the two layers of pleural membrane
- visceral
2. parietal
How much fluid is created by the so membranes
30ml
What is the functions of pleural membrane fluid.
It creates an attraction between the two sheets so that when the parietal membrane is pulled upby the thoracic cavity it pulls up the visceral sheet and the lung. Disruption of the integrity of pleural membrane
Results in rapid equalization of pressure and loss of ventilation function which
Leads to pheumothorase clung collapses
What are the components and functions of respiratory defense system
- mucous cells (goblet cells) and mucous glands (laminate propria) - produce mucous that bathes exposed surfaces.
- Nasal cavity- *cilia sweep mucous and trapped debris/microorganisms
To the pharynx for swallowing - gastric enzymes and acids
*filtration hairs in the nasal cavity removes large particles >10micro meters
Components and functions of LRT defense system
a. Cilia does same function
b. Rate of mucous depend on presence of pleasant stimuli - dusts, allergens or pathogens
c. Alveolar macrophages engulf particles that reach lungs (small)
