Respiratory Physiology Flashcards
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)
state the secondary functions of the respiratory system
-vocalisation (speech)
-olfaction (smell)
-protection of respiratory surfaces 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
define structure of 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
describe the EXPIRATION stage of respiration
thoracic cavity volume decreases—lungs contract—interpulmonary pressure increases=air explelled
what type of transport does expiration require
passive-elastic recoil
describe the strcture of the diaphragm
-large dome-shaped musculotendinous sheet
-seperated thorax from abdomen
-main muscle of respiration
how is the function of the diapgragm
contraction-descends, flattens to increase size of thoracic cavity during inspiration
relaxation-ascends into dome-shape to decrease size of thoracic cavity upon expiration(passive)
describe the structure of intercostal muscle
-lie between the ribs (in the intercostal spaces)
-external intercostal muscles elevate ribs during inspiration
discuss the accessory muscles of respiration
they do not play a primary role in breathing, may be used in laboured/deep breathing. if used at rest a sign of respiratory disease
what is the primary function of the lungs and how does it occur
gas exchange occuring by diffusion
what does the rate of transfer in gas exchange depend on
-the area
-the distance
-the concentration difference (driving force)
the area should be as large as possible, diffusion distance should be as small as possible
what occurs once oxygen is exchanges in the lungs
carried in blood in 2 forms
-by red blood cell bound to haemoglobin (97-98%)
-dissolve in plasma
how many haemoglobin molecules are in the body
280million
why is binding dissociation of O2 with Hb so fast
facilitate transport-necessary because red blood cells are in capillaries for 1 second
how many O2 atoms can Hb bond to
bind upto four O2 atoms
what does O2 saturation (SaO2) refer too
amount of O2 bounf to Hb relative to maximal amount that can bind
what does it mean if a person has 100% saturation
all heme groups of Hb molecules full saturated with O2
what is a pule oximeter used for
-continuous monitoring critical care, anaesthesia
-screening for apnoea
-detecting hypoxia in pilots
discuss CO2 production
in normal healthy conditions
-200ml CO2/min produced
-80 molecules CO2 expired by lung for every 100 molecules of O2 entering
describe carbon dioxide transport
CO2 is carried into body (diffusion)
-7% dissolves in the plasma
-23% bound to haemoglobin
-70% converted to biocarbinate
what is a spirometer used for
measuring function
-when the subject inhales air moves into lungs
-volume of bell decreases, pen rises on training
describe the respiratory condition asthma and the symptoms
a chronic inflammatory disease that causes breathing problems, when airways become narrowed by inflamation or blocked by mucous
symptoms
-wheezing
-coughing
-tightness of chest
-shortness of breathe
what is a treatment for astma
salbutamol inhaler
describe the respiratory disease chronic obstruction pulmonary disease (COPD)
an umberella term used to describe two primary types of obstructive lung disease
1.emphysema
2.bronchitis
describe the respiratory disease chronic obstruction pulmonary disease (COPD)
an umberella term used to describe two primary types of obstructive lung disease
1.emphysema
2.bronchitis
name the symptoms of (COPD)
frequent coughing
wheezing
cough produces lots of mucous
shortness of breathe
tightness of chest
weakness
weight loss
swelling of legs amd feet
describe some of the treatment for COPD
cessation of smoking
stayong up to date in important vaccines
combination therapy
bronchodilater
anti-inflammatory therapy
describe the respiratory condition cystic fibrosis
-a genetic condition that can cause both digestive and breathing problems because the disease makes mucous in the body thick
-the disease can cause specific problems in the lungs such as blockages from thick mucous, trapping harmful bacteria leading disease
what are symptoms of cystic fibrosis
a cough that does not go away
wheezing
shortness of breathe
coughing thick mucous blood
constipation
what are treatment for cystic fibrosis
-medication-antibiotics, steroids, bronchodilaters
-excersise
-airway clearence techniques
-active cycle breathing techniques
diet and nutrition- high calorie
lung transplant
describe sleep apnoea
normal airway-airway is open and air moves through
obstructive sleep apnoe-airway is blocked and air does not move through
