Transcript respiratory system

Functions
Gas exchange between air and circulating
blood
Movement of air into and out of the body
Protection of respiratory surfaces and
defense against pathogens
Producing sounds
Respiratory mucosa
Lines the respiratory tract
Helps to filter debris and microoganisms
Nasal mucosa- prepares the air you
breathe by warming and humidifying it
Pharynx
Chamber shared by the digestive and
respiratory tracts
Larynx
Covered my the epiglottis
Cartilaginous structure surrounding an
opening, ‘the glottis”
Air passing through the glottis vibrates the
vocal folds producing sound waves
Children have short vocal fold- higher
pitched, at puberty the larynx of males
enlarges more than females, resulting in
lower pitched voices
Trachea “windpipe”
Flexible tube surrounded by thin C shaped
pieces of cartilage
Branches to form the left and right
bronchus
The lungs
Right and left lung in the pleural cavities
Base of the lungs rest on the diaphragm
Right lungs has 3 lobes, and left has only
2 lobes. Right lung is slightly larger, due to
heart lying a little more on the left side
Bronchi
Extrapulmonary bronchi prior to entry into
the lungs
Intrapulmonary bronchi after entry into the
lungs
Primary bronchi divide into secondary
bronchi and there is one for each lobe,
R.side has 3 and L. side has 2
Further divide into tertiary bronchi which
supply air to a single bronchopulmonary
segment, the cartilage surrounding bronchi
lessen with each division
Bronchioles
Further division of tertiary bronchi create
bronchioles
One tertiary bronchus supplies air to
about 6500 bronchioles
Made of a lot of smooth muscle and no
cartilage, they control the airflow to the
lungs
Alveolus (air sacs)
Each lung contains 150 million alveoli
Capillaries surround each alveolus
Elastic tissue also surround them to help
with exhalation
Respiratory Physiology
External respiration- exchange of oxygen and
carbon dioxide between the body’s interstitial
fluids and the external environment
Pulmonary ventilation- breathing
Gas diffusion
Transportation of oxygen and carbon dioxide
Internal respiration- absorption of oxygen and
release of carbon dioxide by cells
Pulmonary Ventilation
Physical movement of air into and out of
the respiratory tract
Maintains adequate alveolar ventilationmovement of air into and out of the alveoli
Pressure and air flow to the
lungs
At the start of a breath, P inside and outside the
thoracic cavity are equal
Diaphragm contracts and thoracic cavity size
increases, and P. decreases. This P. difference
cause atm. P. to push air into the body
Diaphragm relaxes, size of cavity decrease and
P. increases, P. inside is greater than outside so
air is forced out.
QuickTime™ and a
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QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Inhalation and Exhalation
Direction of airflow is determined by the
relationship between atmospheric pressure and
intrapulmonary pressure
Respiratory cycle- one inhalation and one
exhalation
M. of Inhal- Diaphragm and external intercostals
M. of Exhal- Internal intercostals, abdominal
muscles
Alveolar Ventilation
Amount of air reaching alveoli each
minute (approx. 4.2 liters/minute)
Air in alveoli contains more CO2 than atm.
Air because the air being exhaled mixes w
air being inhaled