Block 3 Ctb

Front 1

cystic fibrosis

Back 1

alteration of a chloride ion channel protein (CFTR) on submuscosal gland cells causes defective Cl- transport and increased Na+ absorption that results in a more viscous mucous that traps bacteria; interferes with proper function of mucociliary escalator

Front 2

chronic bronchitis

Back 2

repeated damage to mucosa; hypertrophy of mucous glands and smooth muscle leads to wall thickening

Front 3

asthma

Back 3

characterized by airway wall inflammation, hypersecretion of thick bronchial mucous and vasodilation of bronchial microvasculature; prolonged smooth muscle contraction leads to bronchoconstriction during exhalation

Front 4

bronchial carcinoma

Back 4

squamous metaplasia (respiratory epithelium is transformed into stratified squamous) resulting from chronic irritation or from the small grannule cells in the epithelium

Front 5

pneumonia

Back 5

fluid accumulates within the alveoli and reduces the amount of lung parenchyma available for gas exchange

Front 6

emphysema

Back 6

progressive destruction of the alveolar septa leading to enlarged air spaces but a decrease in the surface area available for gas exchange; the amount of elastic tissue is reduced d/t inhibition of alpha1-antitrypsin activity that protects elastic fibers from degradation by proteases

Front 7

lung cancer

Back 7

originate from cells lining the conducting passageways or the distal airways

Front 8

acute respiratory distress syndrome

Back 8

air-blood barrier is compromised by toxins, infectious agents or trauma; fluid leaks from capillaries causing pulmonary edema; fibrin and cell debris accumulate in the alveolar lumen inhibiting surfactant function

Front 9

interstitial fibrosis

Back 9

increased collagen and elastin production by fibroblasts within the interalveolar septum; accumulation of fibrous CT within the septum impedes gas exchange leading to hypoxia

Front 10

what is the composition of pulmonary surfactant?

Back 10

(1) phospholipids (phosphotidylcholine, phosphotidylglycerol)
(2) proteins (surfactant proteins A, B, C, D)
on the alveolar surface, lipids float on a layer of proteins

Front 11

what constitutes the blood-air barrier?

Back 11

-pulmonary surfactant
-type I pneumocyte
-fused basement membrane
-capillary endothelial cell

Front 12

what are the components of the alveolar septum?

Back 12

contains a plexus of continuous capillaries surrounded by fibers of elastin and type III collagen; occasionally openings called alveolar pores are observed; macrophages, lymphocytes, mast cells and fibroblasts are also found in the septum