Histo Midterm 2 - Respiratory System

Question 1

What are Vestibules features and location?

Answer 1

Location: just behind the nares, hairs, and glands

Features: non-keratinized stratified squamous epithelium and lamina propria of dense CT

Question 2

What is the respiratory regions features and location?

Answer 2

Features: PSCC w/G and lamina propria of fibrous CT plus seromucous glands; Extensive venous plexuses

Location: rests on the periosteum of nasal concha

Question 3

What are the Olfactory region’s features and location?

Answer 3

Location: above and under superior concha

Features: Pseudostratified Columnar epithelium (3 cell types), lamina propria (CT with many glands vessels and nerves)

Question 4

What 3 cell types are found in the olfactory region?

Answer 4

Supporting cells - free surface has microvilli mucus
Basal cells - small, single layer at the bottom
Olfactory cells - bipolar neurons, nuclei bellow supporting cells, have nonmotile cilia

Question 5

What are the Paranasal sinuses features and location?

Answer 5

Location: cavities in the frontal maxillary, ethmoid and sphenoid bones of skull

Features: PSCC w/G (has fewer G); drains into nasal cavity

Question 6

What are the Nasopharynx features and location?

Answer 6

Location: back of the nasal cavity

Features: stratified squamous epithelium

Question 7

What is the Larynx?

Answer 7

“Voice box”

Connects pharynx to trachea
Holds airway open
Series of irregular hyaline cartilage held together by fibroelastic CT

Question 8

What does the epiglottis do?

Answer 8

Closes off the airway in the larynx

Question 9

What is unique about mucosa in the larynx?

Answer 9

true vocal fold has non keratinized stratified squamous epithelium

Question 10

What is the difference between false vocal cords and true vocal cords?

Answer 10

False vocal cords - upper mucosal folds; lamina propria has many glands and is loose CT

True vocal cords - lower mucosal folds; core of elastic tissue, muscles, and no glands

Question 11

What are the features of the trachea?

Answer 11

“Wind Pipe”
Has a series of 20 C-shaped cartilage rings

Mucosa - PSCC w/G, lamina propria of loose CT, Thick basement membrane

Submucosa - Dense irregular CT w/ seromucous glands; ends are the perichondrium

Adventitia - C-shaped hyaline cartilage rings, perichondrium, trachealis muscle (smooth muscle connecting open ends of rings)

Mucocillary escalator - cilia provide a coordinated sweeping motion

Question 12

What are the features of the Main Bronchus?

Answer 12

Trachea bifurcates into main bronchi which enter the lungs at the hilum

Question 13

What does the Main Bronchus divide into?

Answer 13

Secondary/lobar bronchi
tertiary/segmental bronchi

these bronchi divide into bronchioles

Question 14

What are the layers of the Main Bronchus?

Answer 14

Mucosa - PSCC w/G in largest, changes to simple columnar w/ cilia as diameter decreases

Submucosa - lots of mucous or seromucous glands and lymph nodules

Adventitia - hyaline cartilage in irregular pieces

Question 15

What are the features of the bronchiole?

Answer 15

Last part of the conducting passageways

No cartilage, glands, or lymphatic nodules

Question 16

What happens to the mucosa of the bronchiole?

Answer 16

Epithelium starts out columnar w/ cilia, but changes to cuboidal as diameter decreases; Goblet cells also decrease in number

Lamina propria is thin with elastic fibers

Smooth muscle beneath mucosa

Question 17

What are the features of Respiratory bronchiole?

Answer 17

Begin the respiratory of the system

Low columnar to cuboidal w/o cilia

Discontinuous

Reduced elastic fibers and smooth muscle

Question 18

What are Clara cells? Location?

Answer 18

Location: Terminal and respiratory bronchiole epithelium; scattered amongst cuboidal lining epithelial cells

Function: Produce and secrete proteins that protect the lining against pollutants and inflammation

Question 19

What is the alveolar duct?

Answer 19

Numerous alveoli and sacs budding off
Squamous epithelium
Last segment to have smooth muscle

Question 20

What are the features of the alveolus?

Answer 20

Simple squamous epithelium and basement membrane

Intralveolar septum - wall between 2 alveoli; 3 types of cells plus capillaries (continuous type)

Question 21

What are the components of the interalveolar septum?

Answer 21

Lining epithelium/type 1 alveolar cell - simple squamous connected by tight junctions

Septal cells/type 2 alveolar cell - cuboidal w/ microvilli; produce surfactant

Alveolar macrophage/dust cell - derived from monocytes; phagocytoses debris in airway

Question 22

How doe Type 2/Septal cells appear under EM?

Answer 22

Multilamellar bodies in cytoplasm (make lipoprotein surfactant)

Question 23

What does surfactant do?

Answer 23

Lines alveolus to lower surface tension and prevent collapse of alveolus

Question 24

What are the 4 layers of the Pulmonary membrane?

Answer 24

1) Surfactant layer
2) Type 1 lining cell of interstitial space
3) Basement membrane
4) Capillary endothelial cell

Question 25

What are the regions of the respiratory system?

Answer 25

Conducting portion - nasal passages thru the bronchioles

Respiratory portion - respiratory bronchioles thru alveoli