Respiratory System Flashcards
What are the 4 processes of respiration
Pulmonary ventilation
External respiration
Transport
Internal respiration
Describe pulmonary ventilation
Moving are in/ out of lungs
Describe external respiration
Gas exchange between the lungs and blood
Describe transport
Transport Oxygen and CO2 between lungs and tissues
Describe internal respiration
Gas exchange between blood vessels and tissues
What are the 2 zones of the respiratory system
Respiratory zone
Conducting zone
What does the respiratory zone consist of
Bronchioles
Alveolar ducts
Alveoli
What is the function of the respiratory zone
Site of Gas exchange
What is the function of the conducting zone
Conduits for air to reach the respiratory zone
What does the conductive Zone consist of
Nose
Nasal cavity
Pharynx
Trachea
List the functions of the nose
Airway Moisten and warm air Filter air Resonating chamber Olfactory receptors
What bones make up the external nose
Nasal
Frontal
Maxillary
Where does the nasal cavity open into
Nasal pharynx
What bones form the roof of the nasal cavity
What forms the floor
Roof: Ethmoid and sphenoid bones
Floor: hard and soft palate
What lines the superior nasal cavity
Olfactory mucosa
What lines most of the nasal cavity
Respiratory mucosa
What does the respiratory mucosa secrete
Lysozyme
Defensins
Describe the function of the conchae
Increase mucosal area
Enhance air turbulence
Help filter
Where is the nasal vestibule
Cavity superior to the nares
What is the function of the sinuses
Lighten the skull
Help warm and moisten air
What is the pharynx
Tube of skeletal muscle that connects the nasal cavity and mouth
And larynx and esophagus
Where does pharynx extend from
Base of skull
To 6th cervical vertebra
What are the 3 regions of the pharynx
Naso
Oro
Laryngo
What area if pharynx is strictly for air
Naso
Where are the pharyngeal tonsils
Nasopharynx
Where does the auditory tube open to
Nasopharynx
Where Does the oropharynx extend from
Soft palate to epiglottis
Where does the nasopharynx extend from
Nasal cavity to soft palate
What is the opening to the oropharynx called
The fauces
From oral cavity to oropharynx
Where are the palatine tonsils located
Oropharynx
Lateral walls of the fauces
Where are the lingual tonsils
Oropharynx
Base of tongue
What is the oropharynx a pathways for
Food
Air
What is the laryngopharyx a pathway for
Food
Air
Where does the laryngopharyx extend from
Epiglottis to larynx
Where do the respiratory and digestive systems diverge
Larynx
Where does the larynx extend from
laryngopharynx to trachea
What are the functions of the larynx
Airway
Route air and food properly
Voice production
What are some of the key larynx cartilages
Thyroid cartilage
Laryngeal prominence
Cricoid cartilage
Describe the epiglottis
Elastic cartilage that covers the the laryngeal inlet
Describe the vocal ligaments
Elastic fibers that form mucosal folds- true vocal cords
Describe the false vocal cords
Mucosal folds superior to true cords
No sounds production
What is speech
Release of air while opening and closing glottis
What determines pitch
Length and tension of vocal cords
How does the pharynx influence vocal production
It resonates
Amplifies
And enhances sound
What determines loudness
Force of air rushing through the cords
When is the larynx closed
Coughing
Sneezing
Valsalvas
Describe valsalvas maneuver
Air is held in by closing the glottis
Intraabdominal pressure increases
Help poop
Help stabilize trunk
Where does trachea extend from
Larynx to mediastinum
What are the 3 layers Of the trachea
Mucosa
Sub mucosa
Adventitia
What is trachea mucosa made of
Goblet cells
Ciliated epithelium
What is trachea sub mucosa made of
Connective tissue
What is trachea adventitia made of
C shaped cartilage rings
What is the carina
Last tracheal cartilage ring
Marks beginning of bronchi
How many branches does the bronchi go through
23 orders
What happens to air reaching the bronchi
Warmed and cleansed
Saturated with water vapor
What do the walls of the bronchi mimic
Trachea walls
What changes to the bronchi structure as they get smaller
Cartilage changes
Epithelium type changes
Amount of smooth muscle increases
What is the structure of bronchioles
Cuboidal epithelium
Circular smooth muscle
Lack cartilage and mucus producing
When does the respiratory zone begin
As terminal bronchioles go into respiratory bronchioles
What do the respiratory bronchioles lead to
Alveolar ducts
Then to terminal Clusters of alveolar sacs
What accounts for most of the lungs volume
Alveoli
Tremendous surface area
What are special features of alveoli
Surrounded by elastic fibers
Contain pores to. Connect each other
What is an important function of the alveoli pores
To equalize air pressure in lung
What is the air blood barrier composed of
Alveolar and capillary walls
Fused basal laminas
What is the respiratory membrane composed of
Air blood barrier
Alveolar walls
Surfactant
Describe the alveolar walls
Single layer of type one epithelial
Type two cells
House Macrophages
How does the respiratory membrane form follow function
Thin walls permit gas diffusion
What do type 1 cells secrete
Angiotensin converting enzyme Ace
What do type 2 cells secrete
Surfactant
What is the liquid coating of the alveolar surface trying to do
Reduce alveoli to smallest size
What is the function of surfactant
Reduce surface tension
Keep alveoli from collapsing
What does the hilus contain
Pulmonary and systemic vessels
How many lobes does right lung have
3
Oblique and horizontal fissures
How many loves does left lung have
2
Cardiac notch
Parietal pleura covers
Thoracic wall
Around heart and between lungs
Visceral pleura covers
The external lung surface
What is pulmonary ventilation
Moving air in and out of the lungs
What does pulmonary ventilation depend on
Volume changes in the thoracic cavity
What do volume changes lead to
Pressure changes
Causes has flow to equalize pressure
What law describe the relationship of gas and pressure
Boyles law
Occurs for quiet inspiration
Diaphragm lowers to increase volume
External intercostals contact and ribs rise
What occurs during quiet expiration
Diaphragm relaxes- rises
External intercostals drop ribs
Thoracic volume decreased
Passive process- relax
Describe forced inspiration
Diaphragm contracts and lowers- increase volume
Ribs rise
Many muscles involved
What muscles are involved with forced inspiration
External intercostals
Pectoralis minor
Scalenes
Sternocloidomastiod
Describe forced expiration
Diaphragm relaxes and rises
Abdominal wall contracts pushing diaphragm higher
Internal intercostals contract dropping ribs
Thoracic volume decreased
How is respiratory pressure described
Relative to atmospheric pressure
Where is the intrapulmonary pressure
Within the alveoli
Where is the intrapleural pressure
Within the pleural cavity
What pressure fluctuates with breathing
Intrapulmonary
Equalizes with atmospheric pressure
What pressure is always less
Intrapleural or intrapulmonary
Intrapleural pressure
Why do lungs expand
Due to the elasticity of thoracic wall
Lungs press against wall
What causes a pneumothorax
The intrapleural pressure equalizing with pulmonary
Caused by a hole
Lung collapses
What 3 major principles govern airflow
Flow from Higher to lower pressure
Changes in volume result in changes in pressure
Changes in tube diameter change resistance
Where is the major source of resistance
Medium sized bronchi
Why is resistance not high in bronchioles
There are many of them
Compensate for small diameter
What happens to breathing as resistance increased
Breathing becomes more strenuous
What can cause obstructed bronchioles
Asthma attack
Cured with epinephrine
Dilate bronchioles
List the 4 respiratory volumes
Tidal
Inspiration reserve
Expiratory reserve
Residual
Tidal volume
air into and out of lungs each breath
Inspiratory reserve volume
Air that can inspired forcibly beyond tidal inspiration
Expiratory reserve volume
Air that can be evacuated from the lungs after tidal expiration
Residual volume
Air left in lungs after forced expiration
List the 4 respiratory capacities
Inspiratory
Functional residual
Vital
Total lung
Inspiratory capacity
Total amount of air inspired after a tidal expiration
Irv
Tv
Functional residual capacity
Amount of air remaining after tidal expiration
Rv
Erv
Vital capacity
Amount of exchangeable air
Tv
Irv
Erv
Total lung capacity
Sum of all lung volumes
What can a spirometer distinguish between
Obstructive pulmonary disease
Restrictive disorders
What is obstructive pulmonary disease
Increased resistance
What is a restrictive disorder
Reduction in lung capacity from lung changes
What is dypsnea
Labored breathing
Gets progressively worse
What does chronic obstructive pulmonary disease cause
Dypsnea
Coughing
Infection
Prevents air from leaving lungs- hyperinflate
What increases when lungs hyperinflate
TLC
FRC
RV
What are 2 forms of chronic obstructive pulmonary disease
Describe each
Emphysema- alveoli loose elasticity
Chronic bronchitis- airways thick and clogged shallow breaths
What is a common trigger of COPD
Smoking
What are restrictive disorders caused by
TB
Asbestos
Reduced amount of healthy lungs
What volumes and capacities change from restrictive disorders
Reduction of VC TLC FRC RV
What is Dalton’s law
Pressure exerted by gases is sum of partial pressures
What is henrys law
Each gas dissolves in liquid according to its partial pressure
What influences how gas dissolves
Partial pressure
Temperature
Solubility
What has is most soluble
Carbon sioxide
What has is practically insoluble
Nitrogen
What mixture of air do alveoli contain
Inspired air and air from previous cycle
Higher in CO2 than atm
5 reasons diffusion Is efficient at respiratory membrane
Distance is small Gas is lipid soluble Huge surface area Blood flow and air flow are coordinated Differences in partial pressure
Describe ventilation perfusion coupling
Blood flow greatest around alveoli with most o2
Bronchioles dilate when co2 is high
What is the partial pressure of o2 in venous blood
40
What is Po2 in alveoli
104
What gas has a high gradient
O2
Higher in alveoli
Blood is oxygenated as if flows past alveoli
What compensates for lower co2 gradient
Solubility in plasma
Allows it to diffuse in equal to 02
What is the o2 pressure gradient between blood and tissues
Low in tissue
High o2 in blood
What are the pressures of o2 and co2 in the blood
O2 40 mm
Co2 45 mm
What influences the 02 saturation of Hb
The pressure of o2
More oxygen= more affinity
When is Hb almost completely saturated
At 70 mm
What is significant about the total Hb saturation point
It is low enough that Hb can be fully saturated even when o2 levels Are low
How much o2 is unloaded in one cycle
20- 25%
Why is the partial unloading of o2 important
Respiratory rate doesn’t need to increase for more 02 to reach the tissues
More can dissociate
What happens to Hb saturation as temp rises
It releases more 02
Curve shifts right
What happens to Hb saturation when temp decreases
Binds o2 tightly
Curve shifts left
What occurs as cells use 02
Increase co2
Increase H
Decline Ph
Acidosis
What does an increases ph do to Hb saturation
Weakens Hb oxygen bond
Increased unloading
Bohr effect
What 3 forms is co2 transported in blood
Plasma 10%
Bound to globin 20%
Bicarbonate 70%
Where does the change of Co2 to bicarbonate take place
RBC
Via carbonic anhydrase
Where is bicarbonate transported
In the plasma
Describe how co2 changes into bicarbonate
Co2 with water= carbonic acid
Carbonic acid dissociatates into H and bicarbonate
Via carbonic anhydrase
What is the chloride shift
In RBC
Bicarbonate out
Chloride in
What does a low ph enhance
Oxygen unloading- Bohr
What takes place for gas trabsport when blood reaches lungs
Bicarbonate becomes co2 again- in RBC
Co2 diffuses into alveoli
Describe the haldene effect
Amount of co2 transported depends on o2
When does co2 get transported best
When low ph
Less affinity for oxygen
Co2 can bind
What occurs if H increases in blood
H is removed by binding to bicarbonate
What happens when H declines in blood
Carbonic acid dissociates
Releasing H
What does hypo ventilation cause
Co2 accumulates
Carbonic acid increase
Ph drops
Acidosis
What does hyperventilation cause
Flushes co2 out
Reduces carbonic acid
Increase ph
Alkalosis
When does hyperventilation occur
To compensate for acidosis
Responsibility of pins respiratory center
Smooth inspiration/ expiration
Modify medulla activity
What is the pacesetting respiratory center
VRG
What does VRG do during inspiration
Fire neurons exciting muscles
What happens to VRG during hypoxia
Gasping
What can inhibit VRG
Morphine
Alcohol
Function of DRG
Integrate input form peripheral receptors to VRG
Where are central receptors
Medulla
Where are peripheral receptors
Blood vessels of neck
What are the 3 most important chemical stimuli
Co2
O2
H
What monitors co2 levels
Indirectly central receptors
Via H ion concentration
When is hyperventilating a proper response
Rising co2 levels
CSF has High H
Ph drop
What happens when hyperventilation is not proper response
Low co2 levels
Reduced brain perfusion
Fainting
What monitors o2 levels
Peripheral receptors
In aortic and carotid
How large of an o2 drop is needed for peripheral receptors to stimulate increased ventilation
To 60mm or lower
Substantial drop
When does ph level modify respiratoryp rate
When ph is too high or low
Even if carbon dioxide and oxygen levels are normal
What are some causes of acidosis
Carbon dioxide retention
Accumulation of lactic acid
Excess ketone or fatty acid- DM
What receptor type responds to Ph
Peripheral
What type of breathing does hypothalamus control
Emotional
Limbic
What type of breathing Does cortex control
Voluntary
Bypass medulla control
