Histology: Respiratory System

Front 1

Name 2 parts of respiratory system.

Back 1

Conducting and Respiratory

Front 2

Describe conducting portion of RS.

Back 2

Regulates airflow to allow phonations. INcludes larynx, bronchi, bronchioles, terminal bronchioles

Front 3

Describe respiratory portion of RS.

Back 3

Site of gas exchange, respiratory bronchioles, alveolar ducts and sacs, alveoli

Front 4

What is meant by conditioning air?

Back 4

Warming and humidifying it and then draws air over vascularized mucousal epithelium (warm and wet)

Front 5

What is meant by cleansing air?

Back 5

Mucous and serous secretion of resp epithelium makes a sticky sheet like carpet. Cilia on sheet beat in a direction which moves sheet up to pharynx to be swallowed or expectorated.

Front 6

How is carpet of mucous moved?

Back 6

By action of ciliated epithelial cells.

Front 7

What are the unique features of a conducting airway?

Back 7

larynx, epiglottis, plate of elastic cartilage.

Front 8

What is larynx?

Back 8

Several cartilagenous plates, some hyaline, some elastic.

Front 9

What is epiglottis?

Back 9

Flapper valve of trachea that protects larynx. Covered with non keratinized wet stratified epithelium

Front 10

What is plate of elastic cartilage?

Back 10

Upper surface- stratified squamous, lower surface- strat squamous transitions to resp epithelium with mixed serous and mucous glands.

Front 11

What are two folds of larynx?

Back 11

true (vocal) cord fold, false (vestibular) cord fold.

Front 12

Better to have growth on true or false cord of larynx?

Back 12

True because not vascular.

Front 13

What does false cord look like in slide?

Back 13

Loose ct, fat cells, dk staining basal layer, stratified.

Front 14

What does true cord look like in slide?

Back 14

Epithelium strat squamous, dense regular CT, eosinophilic bundles of skeletal muscle fibers to control vocal cord.

Front 15

Describe trachea

Back 15

Series of horseshoe shaped hoops joined by slip of smooth muscle. Lined by ciliated pseudostratified columnar epis that has submucousal glands.

Front 16

What is wet vs dry epithelial tissue?

Back 16

Wet is not cornified and is covered with mucous.

Front 17

What are submucosal tubes?

Back 17

Glandular tubes located in CT deep to epi that connect to surface through duct to keep surface moist.

Front 18

Describe trachea basement layer.

Back 18

Thickest in entire body.

Front 19

Describe bronchi.

Back 19

Cartilagenous plates replace rings, has resp. epithelium, less goblet cells and glands than trachea, abundant elastic fiber, spiral bundles of smooth muscle.

Front 20

Do bronchi have goblet cells and glands?

Back 20

Yes, but rare in small bronchi.

Front 21

How does the bronchi slide look different from the trachea?

Back 21

Large visible areas of alveoli for gas exchange in lungs.

Front 22

Describe bronchiole.

Back 22

Regular- similar to small bronchi but no cartilage, resp epithelium, no glands, abundant elastic and smooth muscle fibers

Front 23

Describe terminal bronchiole.

Back 23

Ciliated simple columnar transitions to ciliated cuboidal. No goblets, clara cells

Front 24

What are clara cells?

Back 24

Plump cuboidal cells that make surfactant (bacteriocide and reduction of surface tension) that helps keep bronchiole open. No glands, no cartilage, abundant elastic and smooth muscle fibers

Front 25

What are respiratory bronchiole?

Back 25

Like terminal but wall has sac like alveoli for gas exchange, epi is ciliated simple cuboidal w/out goblet, clara cells present, walls of resp bronchioles are progressively replaced by alveoli.

Front 26

Describe alveolar sac.

Back 26

walls of resp bronchioles are largely replaced by alveoli with squamous lining cells, knobs of smooth muscle, rest of supporting tissue made of reticular and elastic fiber.

Front 27

Describe alveoli.

Back 27

cup shaped structure made by complex cap bed held together by reticular, elastic fiber and some fibroblast. Cap network draped by a delicate sheet of epis, 2 types of epi in alveoli.

Front 28

Describe type I epis in alveoli.

Back 28

Squamous, predominant type.

Front 29

Describe type II epis in alveoli.

Back 29

give rise to type I, make surfactant, reduce surface tension to keep alveoli open, bacteriocidal

Front 30

Why are there pores b/w alveoli?

Back 30

If clogged region, can still get diffusion and also equalized pressure in lungs. Also allows bacteris to spread through out lung.

Front 31

Why are alveoli thin?

Back 31

For gas exchange

Front 32

What is blood air barrier?

Back 32

Series of obstacles for something to get thru before it can get to RBS. Lumen of alveoli, surfactant, type I epis, basement membrane, cap endothelium, lumen of capillary, RBC

Front 33

What is outside surface of lung called?

Back 33

Pleural surface (actual 2 surfaces- visceral and

Front 34

What if problem with cilia?

Back 34

Can't move mucous.

Front 35

What if problem of viscous mucous?

Back 35

Hard to clear from lungs, causes lung infection.

Front 36

What happens in asthma?

Back 36

Hyper reactive smooth muscle closes airway, epinepherine inhalant opens.

Front 37

What happens from smoke inhalation?

Back 37

leads to loss of elastin and elastic recoil (hard to exhale). Emphasema.

Front 38

What happens in edema?

Back 38

Accumulation of fluid in intercellular space impairs gas exchange.

Front 39

What is bowmans gland?

Back 39

Olfactory gland that makes oderant binding protein (OBP), release it, OBP then binds oderant.

Front 40

What kind of cells line the upper resp system?

Back 40

pseudostratified columnar epis.

Front 41

What are the vocal cords line with?

Back 41

stratified squamous to withstand friction.

Front 42

Give the progressive order of branching in the lower resp system.

Back 42

larynx, trachea, primary (main) bronchi, secondary bronchi, tertiary bronchi, bronchioles, terminal bronchioles, respiratory bronchioles, alveolar ducts, alveolar sacs.

Front 43

Describe the smoothe muscle progression in the lower respiratory system.

Back 43

It lies in teh submucosa and gradually becomes more prominent as airway diameter decreases. SM tone controls diameter of conducting passageways.

Front 44

Describe the progession of secretory glands in the lower respiratory system.

Back 44

Submucosal layer lies beneath SM and contains serous and mucous glands that become less numerous in narrow airways. They are not present beyond tertiary bronchi.

Front 45

Describe progression of cartilage in lower resp sys.

Back 45

supporting skeleton for larynx, trachea and bronchi. prevents collapse of airways. lies outside mucosa, completely absent beyond tertiary bronchi.