Pulmonary Anatomy and Physiology review Flashcards
(42 cards)
The pulmonary airway structures that we need to know well include the following:
○ Trachea
○ Carina
○ Primary Bronchi
○ Secondary Bronchi
○ Tertiary Bronchi
○ Bronchioles
○ Alveoli
Trachea and Carina
○ Trachea- Flexible, semi-rigid tubular structure (“windpipe”).
○ Roughly 2.5 cm in diameter and 12-14 cm in length
● Extends through the mediastinum and
lies anterior to the esophagus.
● Carina- Internal ridge between bronchi
The Bronchi
The bronchial tree is a branched
system of air-conducting passages.
○ Originates at level of Carina
Aspirations often go this direction
Right Primary bronchus is more
vertically oriented
All types of bronchi exhibit some common characteristics:
○ Incomplete rings of cartilage continue
to keep the bronchi patent, although these rings become smaller and less numerous further into the tree.
○ All bronchi are lined with ciliated epithelium to help manage mucus.
○ A complete ring of smooth muscle develops between the epithelium and the cartilage rings
Eventually the bronchi branch
into tubules less than ___ mm in
diameter (no more cartilage).
1-2
Ciliated cells are replaced by
____ lining the bronchioles.
simple cuboidal or columnar
epithelium
Instead of cartilage keeping them patent, bronchioles have a _____
thicker layer of smooth muscle
The ____ is a thick layer of smooth muscle that helps regulate airway constriction or dilation.
muscularis
____ regulates the amount of air traveling
through the bronchial tree
Constriction or dilation of the bronchioles
What are the supporting
cells of the lungs that lay within the pulmonary interstitium?
Includes alveolar and capillary epithelium,
basement membrane, and perivascular/perilymphatic tissue
___ Pulmonary Arteries take oxygen-depleted blood from the right ventricle into the lungs
Two
Normal arterial pressure
within the pulmonary arteries is:
○ Systolic- 15-30 mmHg
○ Diastolic- 8-15 mmHg
Terminal bronchioles
branch into ____ , which
eventually terminate at
the ____
Respiratory bronchioles; Alveolar Pore
Each alveolus is encased in _____
pulmonary capillaries and supportive tissue
There are two types of cells in alveolar wall:
○ Alveolar Type 1- The predominant cell
type that promotes gas diffusion
○ Alveolar Type 2- Less common than
type 1, secretes Pulmonary Surfactant
Surfactant
fluid composed of lipids and proteins
that coats the inner surface of the alveoli.
● The purpose is to reduce surface tension and
prevent collapse of the alveoli during exhalation
In the womb, a fetus starts producing
surfactant in ___
the third trimester
____ is where CO2 is exchanged for O2 by the process of simple diffusion
The Alveolar-Capillary complex
Most O2 in the blood is bound to
hemoglobin in the form of
_____
Oxyhemoglobin
The large majority of CO2 in the
blood is transported in the form of
____
Bicarbonate (HCO3-)
____ has a higher PCO2 than
air in the Alveolus, so CO2 moves into
the Alveolus.
Venous blood
Partial pressure of ____ mmHg
correlates with O2 saturation of
approximately ____
60; 90%
A serous membrane called ____ lines the outer surfaces of the lungs and the adjacent internal thoracic wall.
Pleura
