provides oxygen and carbon dioxide exchange between blood and air
serves for speech and vocalization
sense of smell
pH regulation (via CO2)
aids in angiotensin II synthesis (blood pressure)
Assists CV system - respiratory pumps (venous/lymph return)
dissolves blood clots
List the structures that are included in the upper respiratory tract:
nose
pharynx
larynx
list the structures of the lower respiratory tract:
trachea
bronchi
alveoli
describe the structure and fxn of the nose:
fxn: warms, cleanses, and humidifies inhaled air, detects odors, serves as a resonating chamber that amplifies the voice,guard hairs/mucous traps tiny particles
the nasal concha: creates turbulent air flow
describe the structure and fxn of the nasal septum
perpendicular plate (ethmoid bone)
septal cartilage
vomer
describe the structure and fxn of the pharynx:
nasopharynx: receives air only
oropharynx: passes air, food and drink
laryngopharynx: passes air, food, and drink
the respiratroy and digestive system share the oropharynx and laryngopharynx
describe the structure and fxn of the larynx:
voice box, keeps food and drink of out of the airway
epiglottis: closes the airway and directs food and drink into the esophagus
thyroid cartilage: shieldlike, adam's apple
cricoid cartilage: ringlike, connects layrnx to trachea
hyoid bone
vestibular folds: no role in speech, close larynx during swallowing
vocal cords: produces sounds as air passes between them
glottis: the vocal cords and the opening between them
describe the effects of testosterone on the vocal cords:
produce longer/thicker vocal cords
vibrate slower and lower pitch
taut cords: produce higher pitch
looser cords: produce low pitch
speech is produced by pharynx, tounge, mouth and lips
describe the structure and fxn of the trachea:
windpipe
16-20 C shaped rings, reinforce the trachea and keep it from collapsing when you inhale
hilum: how the lung receives the main bronchus, blood vessels, and nerves
main bronchi: 1st degree
superior lobar, middle lobar, inferior lobe bronchus: 2nd degree
asymmetrical: R lung shorter, liver interfers so 3 lobes, L lung, heart interferes so 2 lobes
desribe the bronchial tree and its relation to the airways:
conducting zone: air flow only - nasal cavity, pharynx, trachea, main bronchus, lobar bronchus, segmental bronchus, bronchiole, smooth muscle and cartilage
*
cillary elevator stops in between
*
reapiratory zone: gas exchange, no cartilage, includes, terminal broonchioles, respiratory bronchioles, alveloar ducts (8 x 108)
describe the structure and fxn of the alveloi anatonmy:
low blood pressure
ensures only absorption of fluid, not filtiraion, so no pulmonary edema
capillary networks around alveoli
list the alveloi cells and their fxns:
Squamous (type I) alveolar cell: covers about 95% of alveolar surface area, thin, layer provides rapid gas exchange
great (type II) avleolar cell: 5% of surface, repair squamous (type I) cells when damaged, secrete surfactant
alveolar macrophages: most abundant, phagocytize dust, debris, bacteria,
describe the structure and fxn of the pleurea:
fxn: reduces friction, when breathing, creates a negative pressure that keeps the lungs inflated, cmpartmentalization of each lung
intrapuleural fluid: only a few mL
parietal pleura: attached to the throacic wall, mediastinmum, inner surface of rib cage, superior diaphragm
visceral plurea: covers the surface of the lung, serous membrane
Contraction of which muscles are required for normal/quiet inspiration?
pectoralis major and pectoralis minor
sternocleidomastoid and erector spinae
diaphragm and intercostal muscles
rectus abdominis and external abdominal obliques
diaphragm and intercostal muscles
The fact that pressure decreases when volume increases is the principle behind what law?
Charles' Law
Henry's Law
Dalton's Law
Boyle's Law
Breuer's Law
L.A. Law
boyles law
____________is the temporary cessation of breathing.
eupnea
hyperpnea
apnea
dyspnea
hypopnea
apnea
During inspiration, air flows into the lungs because:
the temperature inside the lungs is less than the atmospheric temperature.
the volume of the lungs is decreased by muscle contraction.
the pressure inside the lungs is less than the atmospheric pressure.
the bronchioles are dilated by an increase in PSNS activity.
none of the above; inspiration is a passive process.
the pressure inside the lungs is less than the atmosphereic pressure
The stretchability or ease with which the lungs can expand is called _____________.
Which of the following will increase the efficiency of oxygen exchange in the alveoli?
decreasing the partial pressure of oxygen in the atmosphere
increasing the partial pressure of carbon dioxide in the atmosphere
emphysema
dilating the pulmonary arteries near well-ventilated alveoli
increasing the thickness of the respiratory membran
dilaing the pumonary arteries near well-ventilated alveoli
Most of the oxygen in the blood is __________; and most carbon dioxide is transported as _______.
bound to hemoglobin; bicarbonate
dissolved gas; water
dissolved gas; dissolved gas
bound to hemoglobin; water
bound to hemoglobin; bound to hemoglobin
bound to hemoglobine; bicarbonate
The partial pressure of oxygen in arterial blood is ________; whereas the partial pressure of carbon dioxide in venous blood is ________.
explain the mechanisms of the nerual control of breathign and the factors that modulate respiratory rhythm:
pontine respiratory group (PRG): modulators of respiratory rhythm, receives input from hypothalamus, limbic system, cerebral cortex, adapts breathing to sleep, excerise, speech, emotions, under voluntary control
dorsal respiratory group (DRG): intergrator, inputs from PRG, hypothalamus, medulla oblongata, chemorecptors ( CO2/pH), stretch and irriant receptors, outputs to the VRG
ventral respiratory group (VRG): primary involunatary generatory in meduall oblongata, output to muscles, inspriatory neurons 2 sec., expiratory neurons 3 sec. = 12 breaths/min., pattern generator to spinal cord/muscles of respiration
explain the mechanism of Boyle's law and how it applies to the pricniples governeing respiratory airflow:
Boyles law: the pressure of a given quantithy of gas is inversly proportional to its volume. If the lungs contain a quantity of gas and lung volume increases, their internal pressure (intrapulmonary pressure) falls.
inspiration: P alveoli (low ) < P atm (high)
expiration: P alveoli (high) > P atm (low)
Airflow: high P to low P
no flow: P atm = P alveoli
How does P change? volume
explain the mechanism of events and pressure changes that occur throughout the respiratory cycle:
at rest: pressure relavitve to atmospheric pressure; chest wants to expand outward, lung elasticity wants to recoil inward; no flow- P atm = P alveoli; pleura stuck together by intrapleural (IP) fluid; negative IP pressure (slight vaccum) - IP pressure = -4mmHg, holds lungs open
inspiration: muscles contract; increases the volume in the throacic cavity - increase lung volume; increase lung volume - decrease pressure, so air flows in: P atm > P alveoli (0> - 3), until P atm = P alveoli
expiration: muscles relax; decrease volume in throacic cavity - decrease lung volume, air flows out; P alveoli > P atm (3 > 0) until P alveoli = P atm
pnemothroax: air in chest; P (IP) goes from -4 to 0, since nothing holds lungs open , then inwards recoil and collapse, atelectasis- collapsed lung or partial breath
describe how airway radius affects resistance to airflow:
bronchodilation: an increase in the diameter of a bronchus or bronchiole, an increase in radius leads to a decrease in resistance; epinephrine and the SNS stimulate bronchodilation and increase airflow
bronchoconstriction: a reduction in diameter; decrease in radius leads to an increase in resistance; internal stimulants - PSNS, ACh, histamines, interleukins, external stimulants - cold air, chemical irritants, asthema
asthema/inflammation- bronchonconstriction, treatment is bronchodilation/anti-inflammatory drugs
describe how pulmonary compliance affects resistance to airflow:
pulmonary compliance: the ease with with the lungs expand or stretchability; expansion based on pressure changes - change in lung volume relative to a given pressure change
increased compliance: floppy lungs, easy to inhale, hard to exhale; emphysema; "spent" ballon
decreased compliance: stiff lungs; shallow breathing, expand less; TB, black lung disease; throacic expands normally, but lungs expand little
describe how surface tension affects resistance to airflow:
alveoli have a slight moisture lining
H-bonds attract water molecules to each other, creating surface tension, which leads to increase collapse
fix: surfactant ; "detergent like";contains amphiphilic proteins and phospholipids - partially hydrophobic, so spread out over the surface of the water film *** reduces surface tension***; increased by type II cells
Newborn respriatory diestress syndrom: no surfactant; decrease compliance; increased work breathing - alveloar collapse
define anatomical dead space and distinguish between alveolar and minute ventilation:
air that actually enters the alveoli becomes available for gas exchange, but not all inhaled air gets that far
anatomical dead space: this air cannot exchange gases with blood; fills the conducting division of the airway; left over from preceeding breath; inspired air (TV) 500 mL - left over air (dead space) 150 mL = 350 mL ventilates into the alveoli
*must account for dead space when calculating alveolar ventilation
alveolar ventilation rate: most directly relevant to the body's ability to get oxygen to the tissues and dispose of carbon dioxide; respiratory rate X (TV - dead space) = AVR - the amount of fresh air moved/minute 4.2L/min
minute ventilation rate: the amount of air inhaled per minute; respiratory rate X TV = mvr - amount of air moved per minute, 6L/min
how does change rate and depth affect ventilation
MVR: same - example; respiration rate (24) x TV (250) = 6000 mL/min
AVR: fast shallow breaths example; respriation rate (24) X TV- dead space (250 - 150) = 2400 mL/min; *not effective ventilation, exchange rate decreases
AVR: slow deep breaths example; respiration rate (6) X TV- dead space (1000 - 150) = 5100mL/min; * more effective than normal
*** depth is more important than rate**
unusable is constant, hyperventilation (increased rate) vs. excerise (increased rate and increased depth)
define, know the normal values/proper units for and discuss the importance of tidal volume:
tidal volume: the amout of air inhaled and exhaled in one cycle during quite breathing
normal value: 500 mL
define, know the normal values/proper units for and discuss the importance of inspiratory reserve volume:
inspriatory reserve volume: the amount of air in excess of tidal volume that can be inhaled with maximum effort; during forced inspiration
normal value: 3,000 mL
define, know the normal values/proper units for and discuss the importance of expiratory reserve volume:
expiratory reserve volume: the amount of air in excess of tidal volume that can be exhaled with maximum effort; during forced expiration
normal value: 1,200 mL
define, know the normal values/proper units for and discuss the importance of residual volume:
residual volume: the amount of air remaining in the lungs after maximum expiration ( foreced expiration); the amount that can never be volunatrily exhaled
normal value: 1,300 mL
define, know the normal values/proper units for and discuss the importance of fuctional residual capacity (FRC):
FRC: the amount of air remaining in the lungs after a normal tidal expiration
normal value: 2,500 mL
how to calculate: RV+ ERV
define, know the normal values/proper units for and discuss the importance of inspiratory capacity:
IC: the maximum amount of air that can be inhaled after a normal tidal expiration
normal value: 3,500 mL
how to calculate: IC = TV + IRV
define, know the normal values/proper units for and discuss the importance of vital capacity:
VC: the amout of air that can be inhaled and exhaled with maximum effort; the deepest breath possible
normal value: 4,700 mL
how to calculate: VC= ERV + TV + IRV
define, know the normal values/proper units for and discuss the importance of total lung capacity:
TLC: maximum amount of air the lungs can contain
normal value: 6,000 mL
how to calculate: TLC= RV + VC
define, know the normal values/proper units for and discuss the importance of forced expiratory volume
FEV: % of vital capacity exhaled over a given time
normal value: 75-85%/1 second
explain the difference between restrictive and obstructive respiratory disorders and provide examples of each:
restricitve disorders
reduce pulmonary compliance, thus limiting the amount to which the lungs can be inflated.
hard to inflate
decreased vital capacity
example: black lung disease, TB
obstructive disordersinterfere with airflow by narrowing or blocking airway
decreased FEV
decreased airway radius
can't get air out fast
example: asthma and chronic bronchitis (COPD)
describe how smoking affects the respiratory system:
decrease cilia - leads to increase mucos
decrease macrophages activity - leads to increase bacteria, chronic cough and infection
cig smoke as 15 carcinogens
causes one of the more deadly cancers
Explain Dalton's Law in the context of alveolar gas exchange:
the total atmospheric pressure is a sum of the contributions of these individual gases
1. it is humidifed by contact with the mucous membrane, so its PH2O is more than 10x higher than the inhaled air
2. freshly inhaled air mixes wiht residual air left from previous respiratory cycle, so its O2 is diluited and it is enriched with CO2
3. alveolar air exchanges O2 and CO2 with the blood so the PO2 of alveolar air is about 65% of that inhaled air, and its PCO2 is more than 130 times higher
**via diffusion: high concentration to low concentration
*for external respiration
Explain Henry's law in the context of alveolar gas exchange:
the amount of gas that dissolves in the water is determined by its solubility in water and its partial pressure in the air.
a. the PO2 of alveolar air is initially higher thatn the PO2 of the blood arriving at an alveolous. O2 diffuses into the blood until the two are in equilibrium
b. the PCO2 of the arriving blood is initially higher than the PCO2 of teh alveolar air. CO2 diffuses into the alevolus until the two are at equilibrium.
it takes about 0.25 second for both gases to reach equilibrium
diffusion conditionsgases diffused from high (parital pressure) to low PP; higher pressure - more gases dissolved
each gas behaives independently
constant temperature
* CO2 is 20x more soluble than O2
*RBC transit time = 0.75 -0.3 seconds
know the normal pressures of O2 and CO2 throughtout the body:
arterial blood
PO2 is 95 mmHg
PCO2 is 40 mmHg
venous blood PO2 = 40 mmHg
PCO2 = 46 mmHg
describe how pressure gradient affects alveolar gas exchange:
the PO2 is about 104 mmHg in alveolar air and 40mmHg in blood arriving at the alveolus, so O2 diffuses from the air into the blood
the PCO2 is about 46 mmgh in blood arriving at teh alveolous and 40mmgh in alveolar air, so CO2 diffuses from the blood into alveoli
hyperbaric oxygen therapy: treatment with oxygen at greater than 1 atm of pressure, treates gangrene and caronbon monoxidea poisoning
describe how membrane thickness affects alveolar gas exchange:
respiratory membrane between blood and alveoalr air is only 0.5 micorliters thick, presents little obstacles for diffusion, plently of equilibrium time
diseased lung: respiratory membranes become edematous and thick, gases have farther to travel b/w blood and air and cannot equilibrate fast enough, so blood leaving lungs ( to rest of body) has high PCO2 and low PO2
describe how the surface area of the respiratory membrane affects alveolar gas exchange
healthy lung: 70m2 of respiratory membrane available for gas exchange, blood is spread very thinly
diseased lung: elastic tissue breaks down, decrease surface area, decrease gas exchange, leads to low blood PO2
examples: emphysema, lung cancer, and TB
describe how ventilation-perfusion coupling affects alveolar gas exchange:
refers to physicological responses that match airflow to blood flow and vice versa
poor ventilation leads to a low PO2 (decreased pressure in blood vessels) in that region of the lung, this stimulates local vasoconstriction, rerouting the blood to better-ventilated areas of the lung.
increased ventilation (increased air flow) raises PO2 and stimulates vasodilation, increasing blood flow to that region to take advantage of the oxygen availability
for CO2
decreased blood flow leads to reduced PCO2 inthe alveoli, so constriction of the broncioles, leads to decreased airflow, could lead to a blood clot
increased blood flow leads to elevated PCO2 in alveoli, so dilitation of bronchioles, increased air flow, redirected blood flow
explain the mechanisms for the transport of oxygen and know the relative amounts transported in each form:
gas transport: the process of carrying gases fromthe alveoli to the systemic tissues and vice versa
oxygen ~1.5% dissolved in blood
~98.5% is bound to hemoglobin (4O2/Hgb)
arterial blood: ~98% saturated, (4O2/Hgb), bright red
venous blood: ~75% saturated, 3O2/Hgb, dark red
02 Hgb dissocation the relationship between hemoglobin saturation and PO2
at low PO2 there is a rapid increase in oxygen loading as PO2 rises further
at high PO2 levels, Hgb approaches 100% saturation and cannot load much more oxygen
75%- cells can obtain more if needed
exercise - 50% steepness, easy to load/unload, systemic tissues
describe how CO poisoning relationship to gas transport:
carbon monoxide
~210x affinity for Hgb than O2
0.1% CO (closed garage) binds to 50% of Hgb
explain the mechanismes for the transport of carbon dioxide and know the relative amounts transported in each form:
transported in 3 forms: carbonic acid, carbamino compounds, dissolved gas
about 5% finds to the amino groups of plasma
CO2 + H2o > H2CO3 > HCO3 + H+
5% of CO2 is carried in the blood as dissolved gas
70% of exchanged CO2 comes from carbonic acid
23% of schanged CO2 comes from carbamino compounds
7% from the dissolved gas
explain the mechanismes for the systemic gas exchange:
the unloading of O2 and the loading of CO2 at the systemic capillaries
carbon dioxide loading
typically a CO2 gradient of 46 - 40 mmHg from tissue fluid to blood.
CO2 diffuses into bloodstream
reacts with water to produce bicarbonate (HCO3-) and hydorgen (H+)
most of the HCO3- is pumped out of the RBC in exchange for Cl- from blood plasma, called the chloride shift
most of the H+ binds to hemoglobin or oxyhemoglobin, which buffers the intreacelluar pH
Oxygen unloading when H+ binds to oxyhemglobin it reduces the afinity fo hemoglobin for O2
PO2 of tissue fluid is low, pressure gradient of 95 > 40 mmHg from arterial blood to tissue fluid
O2 unloads in tissues
explain the haldane effect:
the rate of CO2 loading is adjusted to varying needs of the tissues, low level oxyhemoglobin enables the blood to transport more CO2
1. oxyhemoglobin does not bind to CO2 as well as deoxyhemoglobin does
2. deoxyghemoglobin binds more hydrogen ions than oxyhemoglobin by removing H+ from the solution
shifts the carbonic rxn H20 + CO2 > HCO3- + H+ to the right, thus allows more CO2 to be transported
O2 binds to Hgb, has decreased affinity for CO2
explain the oxygen-hemoglobine dissocation and understand the factors that affect the curve including temperature and pH (bohr effect)
temperature: increased temperature ( active tissues) promotes O2 unloading, the curve shfits to the right("releasing") // decrease temperature > O2 loading, curve shifts to the left (''loading")
borh effect: (acidity)active tissues generate extra CO2 which raises the H+ concentration, lowers pH. hydrogen ions weaken the bond b/w hemoglobin and oxygen and promote oxygen unloading
drop in pH shifts the curve to the right (''releasing")
increased acid (decreaed pH) or acidosis, increase O2 loading
unloads more oxygen at higher temps
unloads more oxygen at lower pH
discuss in detail how pH, CO2, and O2 influence the regulation of the respiratory rhythm:
CO2 directly relates to pH, increases CO2 > increased H+ > decreased pH
central chemoreceptors: near DRG receptors
in blood brain barrier: Co2 easily crosses, H+ does NOT easily cross BBB, increases the central chemorecptor firing
peripheral receptors: less sensitive, stimulated by increased CO2, increased pH, decreased O2 (lower than 60 mmHg), causes increased ventilation
define acidosis:
ablood pH lower than 7.35
define alkalosis:
blood pH greater than 7.45
define hypocapnia:
a PCO2 less than 37 mmHg
define hypercapnia:
a PCO2 greater than 43mmHg
define hyperventilation:
increased pulmonary ventilation in excess of metabolic demand, frequently associated with anxitey; expels CO2 faster than it is produced, thus lowering the blood CO2 concentration and raising the blood pH
define hypoventilation:
reduced pulmonary ventilation; leads to an increase in blood CO2 concentration if ventialtion is insuffient to expel CO2 as fast as it is produced
Understand how asthma effects the respiratory system:
A respiratory crisis triggered by allergens in pollen, mold, food, dust
Allergens stimulate plasma cells to secrete IgE, which binds to mast cells of the respiratory mucosa, causes mast cells to release inflammatory chemicals , which trigger intense airway inflammation.
Understand how pneumonia effects the respiratory system:
Respiratory membranes ( alveolar walls) are thick with edema, and the alveoli contain fluid and blood cells
Understand how chronic bronchitis effects the respiratory system:
The cilia are immobilized and reduced in number, while goblet cells enlarge and produce excess mucus
Understand how emphysema effects the respiratory system:
Alveolar walls break down and the lung exhibits larger but fewer alveoli, so there is much less respiratory membrane available for exchange.
Understand how pneumothorax affects the respiratory system:
The presences of air in the pleural cavity;without the negative intrapleural pressure to keep the lungs inflated, the lungs recoil and collapse
Understand the affects of newborn respiratory distress syndrome:
A deficiency of pulmonary surfactant and then experience great difficulty breathing; treated with artificial surfacant
Understand how respiratory acidosis affectsthee respiratory system:
Occurs when the rate of alveolar ventilation fails to keep pace with the body's rate of CO2 production
Understand how respiratory alkalosis affects the respiratory system:
Results from hyperventilation, in which CO2 is eliminated faster than it is produced.
which of the following is NOT a fxn of th respiratory system?
dissolves blood clots
exchange O2 and CO2 with blood
regulates pH
synthesizes and secretes vitamin B12
synthesizes and secretes vitamin B12
which of the following is TRUE?
B. the bronchi and bronchioles contain smooth muscle
The pressure inside the lungs/alveoli (Palv) at rest is _____ atmospheric pressure (Patm).
C. the same as
which of the following muscles is involved in quite inspriation?
A. external intercostals
Boyle's Law states that:
A. as volume increases, pressure decreases
The part of the central nervous system responsible for the normal breathing pattern is the:
D. ventral respiratory group
air flows out of the lungs during expiration because the:
D. pressure inside the lungs increases
increases SNS activity:
B. causes bronchodilation
Pneumothorax is:
A. when air gets into the pleural space causing the lungs to collapse
food is kept out fo the lower respiratory tract by which of the follwing structures?
D. both B and C
new born respiratory distress syndrome is ususally associated with:
B. a reduction of surfactant
If Pauline's expiratory reserve volume is 1200 mL, her vital capacity is 2000 mL, and her breathing rate is 10 breaths/min, then her minute ventilation rate is _____ ml/min. With a dead space of 500 mL, Pauline's alveolar ventialtion rate is ____ ml/min.
C. 8000/3000
which of the following is FALSE about smoking?
D. smoking increases the number of cilia along the respiratory tract.
The partial pressure of O2 in arterial blood is approximately:
A. 95 mmHg
which of the following describes the Haldane effect?
A. deoxygenated hemoglobin has a higher affinity for CO2 than oxygenated hemoglobin
most of the oxygen in the blood is _____ ; and most carbon dioxide is transported as ____.
B. bound to hemoglobin; bicarbonate
increased oxygen unloading will occur with ____ temperature and ____ pH.
C. increased; decreased
hyperventilation is defined as:
E. an increased in ventilation faster than the rate of CO2 production
which of the following stimulates increased ventilation?