Download 1_ Organisation of resp syst

Allied Science Physiology 09-10. Respiratory System. Lecture 1.
Allied Science Physiology. Respiratory System. Lecture 1.
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Allied Science Physiology. Respiratory System. Lecture 1.
•  External respiration
–  Exchange of oxygen and carbon dioxide between
atmosphere and body tissues
•  Internal respiration
–  Oxidative phosphorylation
Allied Science Physiology. Respiratory System. Lecture 1.
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Pulmonary ventilation (movement of air into lungs and out)
Exchange O2 & CO2 between lungs and blood
Transportation of O2 & CO2 in blood
Exchange O2 & CO2 between blood and body tissues
Allied Science Physiology. Respiratory System. Lecture 1.
Figure 16.1
Allied Science Physiology. Respiratory System. Lecture 1.
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Figure 16.1
Allied Science Physiology. Respiratory System. Lecture 1.
Figure 16.1
Allied Science Physiology. Respiratory System. Lecture 1.
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Figure 16.1
Allied Science Physiology. Respiratory System. Lecture 1.
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Allied Science Physiology. Respiratory System. Lecture 1.
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Allied Science Physiology. Respiratory System. Lecture 1.
Air passages of the head and neck
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Nasal cavity
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Oral cavity
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Pharynx
Figure 16.2
Allied Science Physiology. Respiratory System. Lecture 1.
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Conducting zone
(anatomical dead
space)
Airways from pharynx to
lungs
• Larynx
• Conducting zone
• Respiratory zone
Respiratory zone
Figure 16.2
Allied Science Physiology. Respiratory System. Lecture 1.
•  Trachea
•  Bronchi
•  Secondary bronchi
–  Right side - 3 (to 3 lobes of right lung)
–  Left side - 2 (to 2 lobes of left lung)
•  Tertiary,...Bronchi
–  20-23 orders of branching
Up to 8 million tubules!!
•  Bronchioles
–  Less than 1 mm diameter
–  No cartilage, risk of collapse. To prevent:
walls of elastic fibers
•  Terminal bronchioles
Allied Science Physiology. Respiratory System. Lecture 1.
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•  Air passageway
–  150 mL volume = dead space volume
•  Increase air temperature to body temperature
•  Humidify air
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Goblet cells – secret mucus
and traps foreign particles
Ciliated cells – propel the
mucus up the glotis to be
swallowed
Process: Mucus escalator
Figure 16.4a
Allied Science Physiology. Respiratory System. Lecture 1.
Figure 16.3
Allied Science Physiology. Respiratory System. Lecture 1.
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•  Respiratory bronchioles
•  Alveolar ducts
•  Alveolar sacs
•  Alveoli
Figure 16.5a, b
Allied Science Physiology. Respiratory System. Lecture 1.
•  Exchange of gases between air and blood
by diffusion
•  Respiratory membrane
–  Epithelial cells of alveoli
–  Endothelial cells of capillary
Allied Science Physiology. Respiratory System. Lecture 1.
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Figure 16.3
Allied Science Physiology. Respiratory System. Lecture 1.
•  Alveoli = site of gas exchange
•  300 million alveoli/lung (tennis
court size):facilitate gas exch.)
•  Rich blood supply- capillaries
form sheet over alveoli
•  Alveolar pores
•  Type I alveolar cells –
Make up wall of alveoli, single layer epithelial cells
•  Type II alveolar cells –
Secrete surfactant
•  Alveolar macrophages
Figure 16.5c
Allied Science Physiology. Respiratory System. Lecture 1.
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Barrier for diffusion
–  Alveoli: Type 1 cells + basement membrane
–  Capillaries: Endothelial cells + basement membrane
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0.2 microns thick
Figure 16.5d
Allied Science Physiology. Respiratory System. Lecture 1.
•  Chest wall – air tight, protects lungs
–  Rib cage
–  Sternum
–  Thoracic vertebrae
–  Muscles - internal/external intercostals, diaphragm (lower end)
and neck (upper end)
•  Pleura – membrane lining of lungs and chest wall
–  Pleural sac around each lung
•  Side attached to chest: parietal pleura
•  Sice attached to lung: visceral pleura
–  Intrapleural space filled with intrapleural fluid
•  Volume = 15 mL
Allied Science Physiology. Respiratory System. Lecture 1.
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Figure 16.7
Allied Science Physiology. Respiratory System. Lecture 1.
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