Respiratory System: Lower Flashcards
lower respiratory tract includes…
- larynx
- trachea
- bronchial tree
- lungs
larynx characteristics
- voice box
- composed of hyaline cartilage
- connection b/w pharynx + trachea
- only moves air
- inflammation of larynx mucosa = laryngitis
- paired & unpaired cartilage
larynx: unpaired cartilage
thyroid:
- made of hyaline cartilage
- anterior wall of larynx
- adam’s apple
cricoid: ring of hyaline cartilage
epiglottis:
- formed from elastic cartilage
- cover + protect glottis during swallowing
larynx: paired cartilage
- all 3 made from hyaline cartilage
- arytenoid: attach vocal cords
vocal cords
- ligaments composed of elastic fibers
- folds form vocal cords
- true / false
vocal cords: false
- from superior fold of membrane (vestibule fold)
- helps hold breath
- closes larynx
vocal cords: true
- from inferior folds of mucous membrane
- no blood vessels = pearl white
- produce vibrating sound
- prevents food + liquids from entering trachea
- glottis consists of vocal cords & opening
trachea
- located anterior to esophagus
- connects larynx to left + right primary bronchi
- 20 C-shaped pieces of hyaline cartilage
> open portion faces esophagus allowing for
expansion
> C faces anterior portion + protects against
tracheal collapse - ciliated, pseudostratified columnar w/ goblet cells for mucus secretion
bronchial tree
- stretches from primary bronchi to alveoli ducts
- decreasing amounts of cartilage & increasing smooth muscle from trachea to inner lung
bronchial tree: primary bronchi
- right + left w/ incomplete rings of hyaline cartilage
- branch into secondary (lobar) bronchi
bronchial tree: secondary bronchi
- plates of hyaline cartilage
- 3 in right lung + 2 in left lung
bronchia tree progreession
primary (INC) > secondary (CO) > tertiary (IRR P) > terminal (NA) > respiratory bronchioles (NA) > alveolar ducts (NA)
alveoli
- alveoli ducts > alveolar sacs (multiple alveoli)
- sites for gas exchange
- 300 mill. per lung
- increases surface area for gas exchange
respiratory epithelium
- primary bronchi: ciliated pseudostratified columnar w/ goblet cells
- large bronchioles: ciliated simple columnar w/ goblet cells
- small bronchioles: ciliated simple cuboidal w/o goblet cells
- terminal bronchioles: non-ciliated simple cuboidal
- alveolar ducts: non-ciliated simple squamous
lungs
- right + left are separated by mediastinum
- left lobes: inferior + superior (cardia notch)
- right lobes: superior, middle, inferior
- innervated by nervous system
lungs: pleura
- surrounds lungs
- serous membrane = visceral + parietal layer
- pleura cavity: area b/w 2 pleura membranes containing serous fluid (lubricate, reduce friction, holds lungs to wall)
respiratory membranes consists of…
1) alveolus wall
2) elastic epithelial basement membrane
3) capillary basement membrane
4) capillary endothelium
alveolus wall: type I alveolar cells
- simple squamous epithelium
- site of O2 and CO2 exchange
alveolus wall: type II alveolar cells
- simple cuboidal epithelium
- secrete fluid containing surfactant (lipoprotein + phospholipids that reduce surface tension)
- free surface = microvilli > increase surface area
alveolus wall: macrophages
- remove dust, pollen, debris from air
- move freely across alveolar surface
capillary basement membrane
fused to alveolar basement membrane
capillary endothelium
endothelial cells that form simple squamous layer
mycobacterium tuberculosis
- caused by tuberculosis
- thickens respiratory membrane
- membrane tissue is replaced with fibrous CT (scar tissue)
- decrease elasticity & capacity for gas exchange
ways blood moves to lungs
1) pulmonary circulation
2) systemic circulation
3) bronchial arteries
