PHS 301 Respiratory Physiology Flashcards
What is tidal volume and it’s approx?
Tidal volume (TV). It is the volume of air inspired or expired with each breath during normal quiet breathing.
It is approximately 500 mL in normal adult male.
What is Inspiratory reserve volume (IRV) and it’s approx?
Inspiratory reserve volume (IRV). It is the extra volume of air that can be inhaled by a maximum inspiratory effort
over and beyond the normal tidal volume. It is about 3000 mL (range 2000-3200 mL) in a normal adult male.
What is Expiratory reserve volume (ERV) and it’s approx?
It is the extra volume of
air that can be exhaled by the maximum forceful expiration over and beyond the normal tidal volume, (1.e. after the end
of normal passive expiration). It is approximately 1100 mL in a normal adult male.
Residual volume (RV) and it’s approx
It is the volume of the air that stil
remains in the lungs after the most forceful expiration. It is about 1200 ml in a normal adult male. RV can be calculated from function residual capacity.
What is Inspiratory capacity it’s approx and formula
This is the maximum volume of
the air that can be inspired after normal tidal expiration.
Therefore it equals the tidal volume plus inspiratory reserve volume (TV + IRV) and is approximately 3500 mL in a normal adult male.
What is Expiratory capacity approx and formula?
It is the maximum volume of air
that can be expired atter normal tidal inspiration. It equals tidal volume plus expiratory reserve volume (TV + ERV) and is approximately about 1600 mL in a normal adult male.
What is Functional residual capacity, it’s approx and value?
It is the volume of the air remaining in the lungs atter normal tidal expiration. Therefore it equals the expiratorv reserve volume plus the residual volume (ERV+ RV)and is about 2300 ml in a normal adult male
Components of the upper respiratory tract
nasal cavity
paranasal sinuses
pharynx
larynx above the vocal cords
Components of the lower respiratory tract
lungs
alveoli
bronchi
bronchioles
larynx below vocal cords
trachea
Function of the nasal cavity
The nasal cavity functions to humidify, warm, filter, and act as a conduit for inspired air, as well as protect the respiratory tract through the use of the mucociliary system.
Mucus in the cavity traps inhaled particles whilst cilia drive mucus towards the throat to be swallowed
Inhaled bacteria are destroyed by lysozymes in the nucleus, lymphocytes and antibodies IgA
The nasal cavity also houses the receptors responsible for olfaction in the lining of the roof of the cavity
Function of the bronchi
distribute the air throughout the lungs until reaching the respiratory bronchioles and alveolar sacs
They dialiate and contrict to control airflow
Function of the larynx
protect the lower respiratory tract from aspirating food into the trachea while breathing by mechanism of the epiglottis. It also contains the vocal cords and functions as a voice box for producing sounds, i.e., phonation.
Function of the pharynx and its divisions
supports your respiratory and digestive systems.
Routes air coming from your nose and mouth down to your larynx (voice box), which, in turn, moves air to your trachea and lungs.
Delivers food and liquid to your oesophagus, which sends them onto your stomach
oropharynx:
nasopharynx
laryngopharynx
Function of the paranasal sinus
decreasing the relative weight of the skull, increasing the resonance of the voice, providing a buffer against facial trauma, insulating sensitive structures from rapid temperature fluctuations in the nose, and humidifying and heating inspired air.
Function of the trachea
Function of the alveoli
transports air in and out of your lungs while also conditioning air
this is the site of gaseous exchange where O2 moves in blood in capillaries and CO2 is diffused from blood to alveoli to be exhaled into small air sacs
Function of the bronchioles and mention its divisions from trachea to alveoli
to deliver air to a diffuse network of around 300 million alveoli in the lungs.
Trachea
Primary Bronchi
Secondary Bronchi
Tertiary Bronchi
Bronchioles
Terminal Bronchioles
Respiratory Bronchioles
Alveoli
Function of the lungs
draw oxygen from the air and transport into the bloodstream and remove carbon dioxide from the blood
Non-respiratory frunction of the immune system
Epithelial cells in the mucosal lining of the conducting zone secrete
various molecules that are involved in lung defense mechanism. These include secretory immunoglobulins (IgA), collectins, surfactant proteins
—(SP-A) and (SP-D), defensins, chemokines, cytokines, etc.
What is asthma?
Asthma
Asthma is considered an inflammatory disease of the bronchioles caused
by the hypersensitivity of the bronchioles to foreign substances in the air.
Asthma is a chronic life-long disease with periods of remissions and
exacerbation
Cause of asthma
Functional abnormality in asthma is airway narrowing produced by
following effects of allergic reactions:
* Spasm of bronchial smooth muscle, which is triggered by exposure to
provoking agents such as allergen or exercise,
* Inflammation of bronchial wall (predominantly eosinophilic/producing
mucosal oedema) and
* Secretion of thick mucus into the lumen of bronchioles.
What is the mechanicanism of breathing?
This describes the mechanics that take place to allow a person to inhale and exhale air
2 main physical values involved in breathing
volume
pressure
What is inspiration?
refers to the inflow of air into the lungs when intrapulmonary pressure falls below atmospheric pressue
What is expiration?
refers to the outflow of air from the lungs into the atmosphere when intrapulmonary pressure rises above the atmospheric pressure
