F - Respiratory System - Karius and Cole Flashcards
(24 cards)
Respiratory portion lined by
Pseudostratified ciliated epithelium with goblet cells supported by a lamina propria with seromucous glands and venous plexus
Mucus contains
Mucins MUC5AC and MUC5B
Antimicrobial molecules
Immuno molecules
What cells rest on the basal lamina and secrete hormones?
Basal cells and neuroendocrine cells (NE, cells of Kulchitsky)
Secrete - serotonin, somatostatin, calcitonin, ADH, ACTH
Smoker’s respiratory epithelium
Metaplasia - changed to stratified squamous
More goblet cells
Smoker’s melanosis - benign focal pigment
Trachealis m.
Smooth m. that narrows during cough reflex
Where does cartilage become irregular plates instead of rings
Secondary (lobar) bronchi
Defining characteristics of bronchioles
Cartilage and glands disappear
No gas exchange yet
Club (Clara) Cells
Secrete surfactant that differs from type II alveolar cells
If airway resistance is high airflow
Slow down
More m. effort to produce
What controls the airway resistance? And what is the easiest way to change it?
Smooth m.
Radius
Physiological dead space
Air you took in that did nothing for you + alveolar dead space
In trachea, bronchi, bronchioles
Anatomical dead space
In normal person should equal the phys dead space
-150ml
Alveolar dead space
No blood flow to alveolus or no ventilation
Alveolar ventilation
Volume of air reaching the alveoli
Per minute - VA(dot)
4 L/min
= (tidal volume - dead space) x RR
Perfusion
(Q)
From RV
5L/min
How much O2 and CO2 are exchanged every minute?
O2 - 250ml
CO2 - 200ml
INDEPENDENT of one another
Alveolar gas exchange (J) equation
J = SA x D x (P1-P2)/distance
Alveolar cells
Type I - 40% and cover 90% of surface
Type II - surfactant - reduces surface tension
Heart failure cells
Alveolar macrophages
LV fails to keep pace with venous return from the lungs
How much blood is in cap?
Rest - 70ml
Exercise - 200ml
Emphysema
Irreversible destruction of elastic tissue
serum a1-antitrypsin that neutralizes elastase is decreased
Elastase released by neutrophils destroys elastic tissue
Collagen in interstitial spaces
Increases the diffusion distance and decreases the diffusion of the gases
Under resting conditions RBC spends how much time in pulmonary cap?
.75 seconds
Safety margin - only needs .25s
Main purpose of surfactant?
Changes the surface tension
Reduces surface tension in smallest alveoli more than in large
Prevents collapse
