CH 37: Pulmonary Ventilation Flashcards
Four Functions of Respiratory System–1
1) ________ __________—the inflow and outflow of air between the atmosphere and the lungs.
Pulmonary Ventilation
Four Functions of Respiratory System–2
2) ________ __________—the exchange of O2 and CO2 between the alveoli and the pulmonary capillaries.
Pulmonary Diffusion
Four Functions of Respiratory System–3
3) _____ _______—transport of gases to and from the body’s tissues.
Gas Transport
Four Functions of Respiratory System–4
4) _________ ___________—muscle and pressure contributions to respiration.
Regulation of Ventilation
Anatomy-1
The lungs are comprised of lobes.
• Because the _______ lung has three lobes, the superior lobe, middle lobe and inferior lobe, this lung is slightly larger.
right
Anatomy–2
The _______ lung has two lobes, the superior lobe and the inferior lobe.
left
Respiratory Passageways–1
- Air is taken in through the nose and mouth
- Travels through pharynx and larynx before it enters the ______.
trachea
Respiratory Passageways—2
- Trachea branches into major bronchi and eventually to bronchioles.
- At the end of the bronchioles are the alveolar sacs.
- It is in the alveolar sacs that __________ diffusion occurs— CO2 leaves the capillaries and O2 is taken up and transported via the blood to the body’s tissues.
pulmonary
Passageway Linings–1
- An important challenge of the respiratory passageways is to keep them open to allow air to travel to and from the alveoli.
- The trachea is kept open by multiple _____ _______ that help provide a rigid structure to remain open.
- The walls of the _________ also have cartilage rings but they are less rigid so the lungs are able to expand and contract.
cartilage rings
bronchi
Passageway Linings–2
- In the areas of the trachea and bronchi where cartilage is not present, the walls are composed of ______ ______.
- The bronchioles and alveoli do NOT contain cartilage so are kept open by the ____________ pressures.
smooth muscle
transpulmonary
Passageway Linings–3
- The bronchioles are almost all smooth muscle except for the terminal bronchioles (called ________ _________). These terminal bronchioles are made almost entirely of pulmonary __________ and underlying fibrous tissue.
- Obstructive lung diseases are often a result of excessive __________ of the smooth muscle itself.
respiratory bronchioles
epithelium
contraction
Airflow
• The greatest amount of resistance to airflow actually occurs in the bronchi and some of the larger bronchioles because there are NOT nearly as many larger bronchioles as there are __________ bronchioles. Therefore, there is only a minute amount of air going through each terminal bronchiole.
• However, in disease conditions, it is these smaller terminal bronchioles that are often _________ by (a) mucus and/or
(b) pulmonary edema.
terminal
occluded
Nervous and Local Control of Bronchiolar Musculature–1
_____________ (Constriction)—nerve fibers from the _________ nerves release Ach which will cause mild to moderate constriction of the bronchioles .
Parasympathetic
vagus
Nervous and Local Control of Bronchiolar Musculature–2
Sometimes the parasympathetic nerves are activated by reflexes within the lungs themselves. This _________ _________ reflex is usually in response to irritation to the epithelial membrane by cigarette smoke, dust, noxious gases, bronchial infections, or microemboli occluding the small pulmonary ________.
bronchiolar constrictor
arteries
Nervous and Local Control of Bronchiolar Musculature–3
Two of the most active substances for causing more intense bronchiolar constriction are _________ and slow reactive substance of ___________. These are released in lung tissue by mast cells during allergic reactions and cause airway obstruction.
histamines
anaphylaxsis
Nervous and Local Control of Bronchiolar Musculature–4
___________ (dilation)—there are few direct sympathetic fibers that innervate the central portions of the lungs. However, epinepherine and norepinepherine are carried in the blood and can cause _________ in the bronchioles.
__________ contributes the most as it binds to ____-___________ receptors and causes dilation of the bronchiolar tree.
Sympathetic
dilation
Epinepherine
beta-adrenergic
Mucus Lining and Cilia Action to Clear Passageway–1
1–The respiratory passageways from the nose to the terminal bronchioles are kept moist with a layer of mucus.
2–The mucus is secreted by (a) individual mucous ________ cells in the epithelial lining and (b) small _____-_________.
3–The mucus keeps the passageways moist and mucus helps trap small particles from the inspired air and keeps them from reaching the alveoli.
goblet
submucosal glands