Respiratory system Flashcards
upper tract
nose
pharynx
lower tract
larynx
trachea
bronchi
lungs
nasal cavity
inside nose
delivers clean air to pharynx
hairs trap dust
divided 1/2
respiration
utilisation of O2 in the metabolism of organic molecules by cells
exchanges of O2 and CO2 between an organism and external environment
Functions (8)
provision of O2 elimination of CO2 regulation of pH of blood phonation protection emotional expression muscles: abdominal compression olfactory sensations
5 steps of respiration
- ventilation
- gas exchange
- gas transport
- gas exchange
- cellular respiration
movement of air
because of pressure differences - high to low
low volume = high pressure
high volume = low volume
inspiration/inhalation
diaphragm flattens
muscles elevate ribs and sternum
increased size of thoracic cavity
expiration
muscles depress ribs and sternum
decreased size thoracic cavity
passive - elastic lung recoil
air movement
results from differences between atmospheric pressure and alveolar pressure
at rest = equal pressures
inhalation: atmospheric > alveolar
pleural cavity
space between lung and chest wall
intrapleural pressure:
If Pip < Palv…
alveolar expand
factors affecting pulmonary airflow
- surface tension of alveolar fluid (overcome by surfactant)
- effort required to stretch lung + thoracic wall
- airway resistance - decreases as diameter of airways increases
4 pulmonary volumes
tidal volume
inspiration reserve volume
expiratory reserve volume
residual volume
Tidal volume
amount of air moved into or out of lungs during a normal inspiration of exhalation