week 8 - respiration Flashcards
- Nostrils, nasal cavity and sinuses. Function and form?
FUNCTION
- channel air into pharynx
- warm, moisten & filter air
- connected to olfactory bulbs
FORM
- mucous membrane
- highly vascular
- Pharynx. Function and form?
FUNCTION
- channel air into larynx
- warm, moisten & filter air
FORM
- mucous membrane
- highly vascular
- L-shaped bend
- Larynx. Function and form?
FUNCTION
- channel air into trachea
- modulate vocalisations
- exclude solids & liquids from trachea
FORM
- cartilaginous chamber, rings of muscle
- Trachea. Function and form?
FUNCTION
- channel air into lungs
FORM
- flexible tube
- anterior to oesophagus
- Lungs. Function and form?
- sacs containing airways & blood vessels
- entered via hilum
- divided into lobes by fissures
- Bronchial Tree
from trachea to alveolar ducts
- Alveoli. Function and form?
ALVEOLAR SACS:
- composed of multiple alveoli
ALVEOLI:
- thin film of liquid on inside
- thin membrane with capillary network
Process of ventilation - inhalation?
- diaphragm pulls down
- external intercostal muscles pull ribs out & up
- intrapleural cavity expands
- lungs expand
- air inhaled into lungs
Process of ventilation - exhalation?
- external intercostal muscles relax & ribs return to normal
- diaphragm relaxes & returns to normal
- intrapleural cavity constricts
- lungs constrict
- air exhaled from lungs
What is external respiration?
gas exchange between lungs and blood
What is internal respiration?
gas exchange between blood and cells
How does control of breathing work?
AFFERENT
- chemoreceptors: in CNS & blood vessels, detect blood gas level
- baroreceptors: in aorta & carotid sinuses, detect change in pressure
- chemo/mechano - receptors: in mucous membrane, detect irritants
EFFERENT
- alveolar ventilation rate & depth
- vaso-dilation & constriction
- cough/sneeze reflex
