Week 8 Flashcards
respiratory system consists of
nose, pharynx, larynx, trachea, bronchi, lungs
bronchi has
- primary, secondary and tertiary
- terminal and respiratory bronchioles
- alveolar ducts
- alveoli
how is cartilage replaced by smooth muscle
branching
alveoli anatomy
small, thin walled sacs that have capillary beds in their walls
site of gas molecule exchange between air and blood
respiratory membrane anatomy
separates the air molecules in the alveoli from blood in the capillaries
- average thickness is 0.6 micrometers
- very thin-optimized for diffusion
- very large surface area
- 70 square meters in normal adult
mechanics of breathing
pulmonary ventilation is the movement of air into and out of the lungs
molecules move from areas of high pressure to areas of low pressure
boyles law
the pressure of a has is inversely proportional to its volume
how does movement of air into and out of the lungs work
results from pressure differences between pulmonary air and the atmospheric air
compliance
the amount of volume change in the lung for a given change in alveolar pressure
inspiration
diaphragm descends and external intercostal muscle contract which increase volume of the thoracic cavity and decreases pressure in the thoracic cavity
expiration
passive process at rest
- diaphragm and external intercostal muscles relax thus decreasing the volume of thoracic cavity
- pressure in thoracic cavity increases above atmospheric pressure and air molecules move out of the lung following the pressure gradient
mouth breathing in exercise
air that enters through the nose or mouth is quickly saturated with water vapour and warmed to body temperature, 37 degrees, even under conditions when very cold air is inspired
tidal volume
volume of gas inspired or expired with each breath at rest or during any stated acidity
expiatory reserve volume
maximal volume that can be exhaled from the resting end expiatory position
inspirotiry capacity
maximal volume of gas that can be inspired from the resting and expiatory position
vital capacity
greatest volume of gas that can be expelled by voluntary effort after maximal inspiration
sum of the inspritory capacity and the expiatory reserve volume
residual volume
the volume of gas remaining in the lungs after forced expiration
functional residual capacity
volume of gas remaining in the lungs at the end of a quiet exhalation
total lung capacity
vital capacity plus residual volume
forced vital capacity manoeuver
one in which the subject is instructed to expire as hard and as fast as possible for four seconds
forced expiatory reserve volume in one second
the volume of air expired during the first one second of a forced vital capacity manoeuvre