Respiratory Flashcards
Respiratory system purpose
- Bring O2 into the body and make it available for cellular metabolism
- Get ride of CO2 waste
Respiratory system is divided into
- conducting portion
- respiratory portion
Conducting portion of Respiratory system purpose
To move air from 1 place to another w/o gas exchange
Conducting portion of Respiratory system consists of
interconnected set of tubes and cavities
1. nose
2. pharynx/throat
3. larynx/voice box
4. trachea
5. bronchi
6. terminal bronchi
Respiratory portion of Respiratory system purpose
Gas exchange
1. respiratory bronchioles
2. alveolar ducts
3. alveoli individual
4. alveolar sacs
where does gas exchange occur
respiratory portion of respiratory sys.
respiratory bronchioles
alveolar ducts
alveolar sacs
alveoli
Gas exchange is referring to
O2 and CO2 exchange with blood
Another function of the respiratory system
location of smell receptors are located in the nasal epithelium
nasal cavity provides resonating cavity in the oral cavity to hep shape sounds we produce
gets rid of other waste(alcohol)
Conditioning air in nose does
- filter
- warm
- humidify the air
How does the resp. syst. help with sound
nasal passages Provide a resonating cavity with the oral cavity to shape sounds.
alveoli are covered with
capillary beds for gas exchange
Types of respiration
- pulmonary: ventilation: air movement in and out of the lungs
- external: alveoli and cap
- internal
nose is called
external nares
nasal septum
seperates 2 sides of the upper part of the nasal passages
olfactory epithelium
where we have our sense of smell
Nasal septum connects to
the pharynx
internal nares
opening from the nasal passages to the pharynx
pharynx sections
- nasopharynx
- oropharynx
- hypopharynx/laryngopharynx
fauces
opening between the oral cavity and oropharynx
Nasal conchi purpose
Superior, middle and inferior: creates more surface area for cleaning and humidifying air and turbulance to move the air around
what cells line nasal cavity and nasopharynx
pseudostratified ciliated epithelium with goblet cells
pharynx goes from
internal nares to the cricoid cartilage
eustachian tubes
in the nasopharynx, auditory tubes that connect to the middle ear
oropharynx goes from
behind the mouth to the hyoid bone
oropharynx lined with what kind of cells
stratified squamous epithelium
oropharynx function
passage way for food and drink. stratified squamous epithelium
hypopharynx lined with
stratified squamous epithelium
Hypopharynx function
has openings for larynx to the trachea and to the esophagus. passageway for food and drink.
pseudostrat ciliated columnar epithelium lines a lot of
respiratory pathways
Larynx
=voice box near the hyoid bone just below the thyroid cartilage (forms the adams apple) and cricoid cartilage.
epiglottis made of
elastic cartilage
epiglottis func
close over the larynx to keep food from going down windpipe. attached at the posterior of the thyroid cartilage
Where are the vocal cords
in the larynx
what are the vocal folds
the vocal cords
The Vocal cords have
false and true
vocal cords secondary function
Can catch food if epiglottis missed it
where is the laryngeal sinus
between the false and true vocal cords
between the false and true vocal cords are
the laryngeal sinus
Glottis location
between the 2 true vocal cords
how do the vocal folds work
muscles contract in the larynx and adjusts the tension of the true vocal cords which affect voice pitch
Why are males voices lower
their vocal cords are thicker and longer because of testosterone causing it to vibrate slower
what kind of cartilage is in the trachea
Anteriorly 16-20 C shaped cartilage rings of hyaline cartilage
Posterior: no cartilage
trachealis muscle
thin muscle at the posterior of the trachea
trachea lined with
pseudostratified ciliated epithelium with goblet cells from the 6th Cervical to 5th thoracic vertebra and splits into 2 bronchi
trachea splits into
2 primary bronchi
bronchi outside the lungs
primary bronchi
carina
ridge that is where the primary bronchi start
Wich bronchi is shorter and wider
Right
cough reflex is associated with what structure
carina, has sensitive bit of mucous membrane that triggers a cough
first bronchi inside of the lungs called
secondary bronchi
secondary bronchi split into
tertiary bronchi, 10 on the right and 8 on the left
tertiary broncus becomes what segment
bronchial pulmonary segment, region of the lobe served by a singe tertiary bronchus
Tertiary bronchi becomes what bronchi at the end
terminal bronchiols to respiratory bronchiols to alveolar ducts
when do the cartilagious rings disapear
Slowly as bronchiols branch into smaller branches
smallest bronchioles have what instead of cartilage in the wall
smooth muscle
how many alveoli
300 million/150 each lung
Alveolar wall has what cells
Type1: 95% made of simple squamous epithelium
type2: 5% cuboidal, secretory cells secrete alveolar fluid.
alveolar fluid made of
water and surfactant. forms monomolecular layer over interior surface of the alveolus
surfactant
in alveolar fluid. has phospholipids that lowers the surface tension from the water to prevent the H2O in the fluid from attracting itself and collapsing the alveolus.
Another type of cell in alveolus is
alveoli macrophages
Respiratory membrane
alveolar membrane
what is respiratory membrane entail
layer where gas exchange happens. capillary is close to type 1 cells
path of O2 inhaled
O2 inhaled->alveolus->alveolar fluid->through type 1 cells->thin basement membrane->endothelium inside the capillary
Blood supply from the lung comes from
- Deoxygenated blood via pulmonary trunk and pulmonary arteries
- oxygenated blood from thoracic aorta through bronchial capillaries
Those 2 main sources
Ventilation
pulmonary respiration. movement of air in and out of the lungs
Ventilation is depended on what law
Boyles law: Volume of gas varies inversely with its pressure assuming constant temp. Boyels law=PV
for inspiration to occur
lungs must expand->increase in V-> decrease in lung pressure. lung pressure below ATM p ->air rushes in.
what are the main muscles for inspirations
diaphragm and external intercostals. minor: sternocliedomastoid, scalenes and pectoralis minor
diaphragm distance
1cm resting breath
10cm labored breathing
how do the muscles move for labored inhalation
intercostals contract making the ribcage move out making the chest bigger->increasing lung volume
when at rest and passive expiration the main force is
relaxation of the stretch on elastic fibers around alveoli.
what muscles force air out for expiration
Abdomen muscles: rectus abdominus, transversus abdominus, internal and external oblique
Vislva maneuver
take a breath and hold, contract ab muscles without letting air out->increase pressure on abdomen used in pooping, peeing, clear out eustachian tube
intrapulmonary pressure
pressure in alveoli of the lungs
intrapleural pressure
pressure in the pleural space, usually slightly less than intrapulmonary pressure. due to elasticity of lungs they’re trying to pull inward and away from the pleura
intrapleural pressure at rest
156 mm Hg
sea level pressue
760 mmHG
intrapulmonary pressure at rest
760/same as ATM because no air is moving
intraplearal and intrapulmonary pressure when inhaling
intrapleural 754
intrapulmonary 757-758 difference causes air to rush in because forces want to equalize the pressure and ATM
Expansion intrapleural and intrapulmonary(alveolar) press
756
762-763. more than ATM -> air flows out
advantages of slow replacement
help maintain homeostasis: prevents wide fluctuations between O2 and CO2 concentration in alveoli and bloodstream
how much air is replaced with fresh ATM air with each tidal breath
15% or about 350mm Hg since 150mm still in the conducting tract
MRV
minute respiration ventilation: MRV=TV x repiratitory rate(per minute)
asthma usually from
bronchial constriction
pneumonia
respiratory membrane gets thicker due to edema build up between blood capillary wall and the alveoli. can usually see fluid in alveoli
Emphysema
alveolar tissue destroyed by macrophages which results in reduced surface area. incurable
pulmonary fibrosis
build up of CT in the lung in certain types of lung damage: asbestos, CT fibers added to the lungs so they’re less elastic
O2% in air
21%
N% in air
79%
CO2% in air
.04%
Daltons Law
total ATM pressue is sum of all other pressures
time it takes to do gas exchange
1/4 sec which is 1/3 of the time an RBC is in a capillary adjacent to alveolus
is CO2 or O2 more soluble in water
CO2 20x more soluble in plasma/alveolar fluid
Hemoglobin can carry how many O2
4 O2 molecules
How may hemoglobin in RBC
250million
1RBC can carry how may O2 molecultes
1 billion
how many RBC in microliter of blood
5 million
how many L of blood in the body
5L
main respiratory center is in
the medulla oblongata
breathing rate depends on
repetitive stimuli from the brain. 2 levels
1. normally breath unconsiously/auto
2. can breath differently at will
respiratory rhythm depends on
circumstances: rest, exercise, emotion
what sensory receptors provide info to the medulla oblongata
- central chemoreceptors in brain stem: respond to pH in cerebrospina fluid: info on O2 and CO2 levels in CNA
- peripheral chemoreceptors in carotid and aortic bodies: respond to CO2/O2 levels in Peripheral NS
- Barrow receptors: stretch receptors in smooth muscle of the bronchioles/visceral/pleural membrane responds to overstretching of the lung
- irritant receptors: nerve endings in epithelial cells in the airway. responds to smoke, dust, pollen, ect. can result in coughing or sneezing
pulmonary compliance
how easy/effort for the lungs expand. related to distensibility of the lungs
factors that affect pulmonary compliance
- surfactant
- disease: lungs can’t expand as normal (TB, asthma
- diameter of bronchioles: broncho constriction=constriction of smooth muscle in bronchial walls. parasympathtic stim reduces bronchial diameter. sympathetic nervous system can cause bronchodilation, epinephrine
anatomical dead space
conducting portion of resp. sys. air not available for gas exchange
pathologic dead space
damaged areas of the lungs that isn’t exchanging air
psysiological dead space
anatomical+pathologic dead space: areas that contain air but can’t do gas exchange
AVR
alveolar vent rate. how much air perminute in the respiratory region. 350mL x respiratory rate/min. aka fresh air available for exchange per min
What affects O2 unloading
- ambient partial pressure of O2 (lower partial pressure O2 in tissue=more O2 released due to greater concentration gradient
- Temp: higher temp promotes O2 unloading (when muscle warms up for exercise
- pH: called Bohr effect: oxyhemoglobin dissociated increases so more O2 unloads in response to low pH level active tissue generate more CO2 because it uses more O2. drives the equation for CO2 conversion to bicarb to the right means more H+ ions produces and released into plasma which lowers Blood pH making it more acidic.
- BPG (biphosphoglycerate: intermediates in glycolysis. BPG promotes O2 unload. BPG can bind to hemoglobin->promotes O2 unload because O2 is not as tightly bound to hemoglobin. BPG presense is stimulated by temp, more GH, testosterone, epinephrine, thyroxine. people in high altitude usually have more BPG in systems
Haldane effect
CO2 unloading in tissues.
Reason why haldane effect occures
Low oxyhemoglobin enables blood to transport more CO2 even though it binds to same place
1. deoxyhemoglobin binds CO2 better than oxyhemoglobin
2. deoxyhemoglobin binds/buffers more H+ ions than oxy hemoglobin so removes H+ ions from solution->shifts the equation to the right. High metabolic rate keeps oxyhemoglobin levels relatively low an allows CO2 transport
How does High metabolic rate help CO2 transport
high metabolic rate keeps oxyhemoglobin relatively low allows CO2 transported
Ventilation
movement of air
perfusion
getting blood to areas of the lungs so the gas can be exchanged
What needs to happen for gas exchange to be effective
- Good ventilation of alveoli
- good perfusion of the capillaries
how does the body when a part of the lung is poorly ventilated
the arterioles respond to the partial pressure of O2 and will direct blood to a better ventilated alveoli.
body tries to match ventilation ad perfusion rate with different parts of the lungs in general.
Reasons part of lug may be poorly ventilated
- local vasoconstriction of pulmonary arterioles: will keep blood away from the area
- bronchioles respond to the partial pressure of CO2. If airflow through bronchioles is lower than normal then there is a rise of partial pressure of CO2 causes local bronchodilation to hep get rid of the excess CO2 in the air of the alveolus
- High air flow compared to the blood supply than lower partial pressure of CO2 causes bronchoconstriction so we get proportional amounts of air in the alveolus and blood in the adjacent capillaries
