Transcript system respirtory

The Respiratory System
Overview
 The main function of the system is to allow gas
exchange
 The Respiratory system is divided into an upper
respiratory tract and a lower respiratory tract
 The upper tract consists of the nasal passages,
pharynx, and larynx
 The lower tract includes: trachea, bronchi ( and their
smaller branches), and the lungs.
Upper Tract: The Nose
 Only external part of the respiratory system
 Air enters, passing through external nares
(nostrils) and through the nasal cavity.
 The air is warmed
 Mucus helps to moisten the air and traps
bacteria and other debris
 Mucus is then pushed towards the throat
(pharynx), where it is swallowed and digested
in the stomach
Upper Tract: The Nose (cont)
 Unwanted Particles are also deflected through
the conchae
 Conchae swirls the air and deflects the
particles into the mucus, preventing
unwanted particles from entering the lungs.
 The Nasal and Oral cavity is supported by the
palate, some of which is supported by bone,
(hard palate), and other with little support
(soft palate)
Upper Tract: Pharynx
 Muscular passageway, commonly called the
throat
 Passage for both food and air
 Air enters through nasopharynx, through
oropharynx, to enter larynx below
 Tonsils , are located high up in the
nasopharynx.
Upper Tract: Larynx
 The larynx or a.k.a. the voice box
 Made up of eight hyaline cartilages, including
the thyroid cartilage, commonly known as an
Adam’s apple
 The epiglottis only lets air enter the larynx, if
anything else enters the larynx, the cough
reflex is triggered and the debris is directed
to the esophagus or out of mouth
Upper Tract: Larynx
When there is no swallowing the
passage stays open for air
 The larynx also includes vocal folds,
that vibrate the air when releasing it,
helping us to speak.
 The Larynx also has cilia to filter air
Upper Tract
Lower Tract: Trachea
 Wind pipe
 Tracheal Tube: largest tube in
respiratory system
 Lined with ciliated mucosa, which act in
the opposite direction of the traveling
air
 Repel mucus, filters air
Lower Tract:Bronchi
 Tracheal Tube leads to two branches of
Bronchi
 The right Bronchus is wider and shorter than
the left, and is commonly where unwanted
debris would enter
 Air at this point is mostly warm and filtered
 Smaller branches of bronchi (Bronchioles)
lead directly to air sacs.
Bronchi
Lower Tract:Lungs
 Thoracic cavity
 Apex: narrow,
superior portion of
lungs
 Base: portion of
lung resting on
diaphragm
Lower Tract: Lung
 Left lung has two lobes, the right lung has
three
 Lungs are made up of Stroma, elastic tissue,
easy to expand
 The outer surface of the lungs is covered by
the visceral pluera
 The thoracic cavity is covered by parietal
pleura
 The lung can slide easily because of these
surfaces during breathing
 They resist being pulled apart from each
other
Lower Tract: Lung
 Aveoli: air sacs
 Bronchioles lead air into respiratory zone in
the lungs and into the Aveoli, where there is
gas exchange
 Bronchi serve as conducting zone structures,
leading into and out of the respiratory zone.
 Aveolar pores connect to other air sacs, in
case some of the Bronchioles become
clogged
 Aveoli contains “dust cells” or Macrophages
that pick up bacteria and clean the air sac
Respiratory Membrane
Located in the lungs
Alveoli on 1 side, capillary on other
walls1 cell thick
Gas flows on one side, while blood flows on
the other
 The oxygen diffuses through the membrane
to supply the blood and carbon dioxide enters
the air sacs and is released from the body
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Physiology
 Pulmanary Venilation: gases in air sacs of
lungs are continuously changed, commonly
known as breathing
 External Respiration: Gas exchange between
blood and alveoli
 Respiratory Gas Transport: Oxygen and
carbon dioxide is pumped into and out of
lungs by the bloodstream
 Internal Respiration: Gas exchange between
blood and tissue through capillaries
Inspiration
 Diaphragm and intercostal muscles
contract
 Thoracic cavity enlarged – lung tissue
stuck to sides by pluera - vacuum
 Air sucked in
Expiration
 Passive process: due to elasticity of
lung tissue
Breathing
 Triggered by CO2 level.
Air Volumes
 Tidal volume: normal amount of air in
and out of lungs
 Inspiratory reserve: amount one can
force in after normal breath
 Expiratory reserve: amount one can
force out after normal exhale
 Residual volume: stays in lungs (more
time for gas exchange)
Control breathing
 Medulla sets basic rate
 Pons smooths out the rhythm