histology

Question 1

mucosa

Answer 1

inner region w/ resp epithelium, lamina propria

Question 2

submucosa

Answer 2

middle region w/ seromucous glands

Question 3

adventitia

Answer 3

outer region of trachea, hyaline cartilage

Question 4

lamina propria

Answer 4

thin connective tissue below basement membrane

Question 5

chondrocytes

Answer 5

cartilage cells central to hyaline cartilage

Question 6

trachealis muscle

Answer 6

smooth muscle in trachea, bridges gaps in cartilage

Question 7

diff b/w primary bronchiole and bronchus

Answer 7

no cartilage and less glands, increased SM in primary bronchiole

Question 8

alveolar ducts

Answer 8

linear passages continuous w/ respiratory bronchioles, most distal portion w/ SM cells (appear as knobs)

Question 9

alveolar sacs

Answer 9

outpouchings of numerous alveoli

Question 10

type I pneumocytes

Answer 10

thin cytoplasm, cover 95% of alveolus, form half of blood gas barrier

Question 11

type II pneumocytes

Answer 11

cuboidal, near septal intersections, synthesize surfactant and divide/regenerate to both pneumocyte types

Question 12

lamellar bodies

Answer 12

present in type II pneumocytes cytoplasm, contain phospholipids that contribute to surfactant

Question 13

blood gas barrier

Answer 13

alveolus (type I) cytoplasm and capillary endothelium are on opposite sides of shared basement membrane

Question 14

epithelium changes moving distally

Answer 14

pseudostratified ciliated columnar for bronchus until terminal bronchioles, transition to cuboidal through respiratory bronchioles then simple sqamous in alveoli

Question 15

basal cells (short cells)

Answer 15

rest on basal lamina, dont extend to lumen

Question 16

location and role of club cells

Answer 16

primary and terminal bronchioles, main cell in respiratory bronchioles

divide and can differentiate to ciliated, secrete glycosaminoglycans (surfactant component) metabolize toxins w/ cyt p450

Question 17

primary bronchioles

Answer 17

1mm or less, ciliated w/ goblet cells in epithelium (transitioning to ciliated cuboidal w/ club cells)

no glands or cartilage, but do have SM

Question 18

terminal bronchioles

Answer 18

most distal part of conducting portion, less than 0.5 mm

simple cuboidal w/ mostly club cells and no goblet cells

no glands or cartilage, some SM

Question 19

respiratory bronchioles

Answer 19

transition to respiratory portion, simple cuboidal w/ mostly club cells and some interruptions by alveoli simple sqamous

Question 20

alveolar macrophages structure and fn

Answer 20

dust cells, large and irregular w/ vacuolated cytoplasm, sometimes w/ indented nucleus

remove dust, inhaled particles- migrate to bronchioles after filling then to oropharynx and are swallowed, expectorated, or removed by lymphatics

secrete elastase

Question 21

describe surfactant structure

Answer 21

phospholipids and 4 proteins, has a lower aqueous phase and a superficial lipid phase

B and C proteins required for physiology, A and D for immunity