Respiratory Physiology Flashcards
(51 cards)
state the primary functions of the respiratory system
-gaseous exchange between air and blood
-regulates blood pH
-regulates blood pressure (by producing angiotensin converting enzyme)
-vocalisation (speech)
-olfaction (smell)
-protection of respiratory surface from dehydration, temperature changes and pathogens.
name the anatomical structures/divisions of the respiratory system
-upper respiratory tract (nasal cavity, pharynx (conducts air and food)
-lower respiratory tract (larync to lungs (air only)
name the physiological divisions of respiritaory and their function
CONDUCTING ZONE
-conducts air towards lung (nose, pharynx, larynx, trachea, bronchi, bronchioles, terminal bronchioles)
RESPIRATORY ZONE
-functional zone involves in respiration (respiratory bronchioles, alveolar ducts, alveolar sacs, alveoli)
what are the histological features adapted to conducting zone
respiratory epithelium with mucous cells and the muco-ciliary escalator lines nasal cavity and superior portion of the pharynx. (mainly lined by respiratory epithelium)
what are the histological features of the respiratory zone/finer bronchiols.
epithelium becoes cuboidal
what are the histological features of gas exchange surfaces.
delicate simple squamous epithelium-the distance between the air and the blood in adjacent capillaries is generally less than 1 micrometre.
describe “pseudostratified” epithelium
describes closely packed cells which appear to be in multiple layers (stratified) but are, in fact, all attatched at basement memmbrane
describe “ciliated” epithelium
cilia are tiny hairs on surface of epithelium cells which sweep mucous/debris
describe “columnar epithelium”
epithelial cells appear like tall columns
describe goblet cells
produce mucous which trap particles
define the functions of the external nose and nasal cavity structure
Air Conditioning
-the air outside is dry and cold and so must be moistured and heated
Filtration
-the vestibule of the nose is lined with skin which hairs to trap pollen, pathogens dust ect (contains respiratory epithelium)
Olfaction
-directs air upwards towards the olfactory nerve speech
Vocalisation
-modifies speech vibrations, adds resonance
state the properties of the trachea
-windpipe (15cm long, 2.5cm wide)
-anterior to oesophagus
-distally it bifucrates into left and right primary bronchi
-c-shaped cartilages to keep trachea patent
lined by respiratory epithelium
describe the bifucration of the trachea
-left and right primary bronchi are seperated by CARNIA, the last tracheal cartilage
-carnia is sensitive to mechanical stimuli and stimulates power cough reflex
-right main bronchus is wider and more vertical than left
describe the structure of the bronchial tree
PRIMARY BRONCHI
-left and right
-cartilage rings
SECONDARY BRONCHI
-lobar branch
-2 left, 3 right (mirror lobes of lungs)
-cartilage plates (incomplete rings)
TERTIARY BRONCHI
-segmental
-one to eaxh segment of lung
-cartilage segments
BRONCHIOLS
-no cartilage
-smooth muscle in walls
TERMINAL BRONCHIOLS
-end of conducting zone
-simple cuboidal epithelium
RESPIRATORY BRONCHIOLS
-start of respiratary zone
describe the structure of alveolar sacks
-respiratory bronchiols connect to alveolar ducts
-alveolar sacks are the “bunch of grape-like” structures at distal ends of alveolar sacks
-have very large surface area (500million alveioli in adult lungs)
-surrounded by vast capilary netwrok
describe the alveoli
-the end point of respiaratory system
-ballon shaped structure
-site of gaseous exchange by diffusion across alveolar and capillary wall.
describe the structure of the lungs
-lungs occupy most of thoracic cavity
-extend into root of neck
-LEFT lung has 2 loes (superior/inferior) and one fissure (oblique) due to cardiac notch (space for the heart)
-RIGHT lung has three lobes (superior/inferior/middle) and two fissures (oblique and horizontal)
define the “hilium” of the lungs
the “root of lung” point of which a collection of structures enter and leave the lungs.
bronchi/pulmonary artery/pulmonary veins/lymphatics/nerves
what structures line/surround round the lung
-surrounded pleural membrane
-a continuous membrane with potential space between
-categorised as parietal pleura/visceral pleura.
what is the thoracic cage comprised of
-ribs
-sternum,manubrium and costal cartilage
-thoracic vertebrae T1-T12
what is the function of thoracic cage
-protects viscera
-attatchment site of muscles of respiration
-facilitates respiration
describe the “mechanism of respiration”
-diaphragm contracts, increasing the volume of thoracic cage
-air is then drawn into the lungs when pressure inside lungs (alveolar pressure) is less than atmospheric pressure (high-low)
describe the INSPIRATION stage in respiration
thoracic cavity expands—lungs expands–interpulmonary pressure decreases=draws air in
what sort of transport does inspiration require
active: requires energy for muscle contraction
