Respiratory system chp 23 Flashcards
functions of the respiratory system
- allow for O2 and CO2 exchange between blood and air
- speech, vocalization, and smell
- helps control pH of body fluids
- helps regulate blood pressure (angiotensin II)
- promotes flow and lymph and venous blood
- filters and dissolves small blood clots
- assists in urination, defecation, and childbirth
what are the 2 main divisions of the respiratory system?
- conducting division
- nostrils through major bronchioles
- most of resp. syst. - respiratory division
- alveoli and gas exchange regions
besides the 2 major divisions, what are the 2 subdivisions?
- upper respiratory tract
- (nasal cavity) - nose through larynx - lower respiratory tract
- trachea through lungs
- this is where infections such as bronchitis occur
olfactory epithelium
detects odor
respiratory epithelium
secretes mucus
what are the 3 regions of the pharynx
- nasopharynx
- oropharynx
- laryngopharynx
nasopharynx
air passage with pharyngeal tonsils
oropharynx
common route for food and air (behind the oral cavity)
laryngopharynx
extends to the larynx
larynx does what …
keep food and drink out of airway
extrinsic muscles….
connect the larynx and elevate it during swallowing
intrinsic muscles
control vocal chords
respiratory mucosa
lines conducting passageway portion
- changes along resp. tract
mucus elevator
cilia moves mucus to pharynx
laminate propria
areolar tissue underlying respiratory epithelium that provides support
The respiratory defense system does what and what does it include
filtration mechanisms that protect gas exchange surfaces
- respiratory mucosa
- mucus elevator
- lamina propria
olfactory and respiratory epithelium are in the
nasal cavity/ nose
extrinsic and intrinsic muscles are associated with what structure
the larynx
what is asthma
the constriction of airways in response to irritation
- swelling of mucosa (lining of pathway)
-increased resistance (restricted airflow)
what is chronic bronchitis
long term inflammation of bronchial lining
- overproduction of mucus
- “blue bloaters”
what is emphysema
the destruction of alveolar surfaces and inadequate O2 + CO2 exchange
- “pink puffers”
what are the 3 factors of resistance to airflow/ of the lungs
- diameter of bronchioles
- pulmonary compliance - lung disease
- surface tension - alveoli + distal bronchioles
describe diameter of bronchioles (resistance to airlfow factor) the 2 types and what causes it
a. bronchodilation
- epinephrine (sympathetic)
- reduces resistance
b. bronchoconstriction
- histamine, cold air, and irritants (parasympathetic)
- increases resistance
describe surface tension (resistance to airlfow factor)
relates to alveoli + distal bronchioles
- surfactant deficiency in premature infants
what does resistance of airflow/lungs mean
how much force is required to inflate or deflate them
- higher resistance = harder it is to force air along the conducting passages
what does lower resistance mean
more easily air flows along conducting passages
what is compliances of the lungs
indication of how easily the lungs expand
greater compliance means
lower the tension in the walls of lungs at a given volume
what increases compliance
loss of supporting tissues + destruction of alveoli increase compliance
lower the compliance means
greater tension in lung walls at a given volume and less easily air flows along conducting passages
what lowers/reduces compliance
arthritis / other skeletal disorders that affect the articulations of ribs or spinal column by reducing the elasticity of the chest wall
- respiratory distress syndrome (not enough surfactant production leading to alveolar collapse on exhalation
Hypocapnia
decreased/low CO2 levels so high pH level
you must decrease respiratory rate to go back to normal; homeostasis is restored
hypercapnia
increased / high CO2 levels so low pH levels (acidic) because there is a too much carbonic acid being made
you must increase respiratory rate to go back to normal; homeostasis is restored
what is the primary factor in regulation of breathing rate
CO2
hyperventilation
- anxiety leads to this
- rapid breathing causing blood CO2 levels to drop
respiratory centers receive input from many other sources that affect _____
respiratory rhythm
what receptors provide info to respiratory centers?
sensory receptors mainly the central and peripheral chemoreceptors
also includes
- stretch and irritant receptors
where are the peripheral chemoreceptors located in
aortic arch
+
carotid bodies
what do peripheral chemoreceptors of respiration do?
monitor blood gases + pH levels and it sends info about blood chemistry to DRG receptors
how many pairs of respiratory centers in the brainstem responsible respiratory center are there AND where?
there are 3 pairs of respiratory centers in the medulla and pons
what are the 3 pairs of respiratory centers in Bainstem (medulla and pons)
- Ventral respiratory group (VRG)
- Dorsal resp. group (DRG)
- Pontine resp. group (PRG)
Ventral respiratory group (VRG)
primary generator of respiratory rhythm
- works tg with DRG
Dorsal respiratory group (DRG)
receives input and issues output to VRG to modify rhythm + adapts to varying conditions
- works tg with VRG
Pontine respiratory group (PRG)
receives input, issues output to VRG + DRG to modify breathing depth and duration
What transports oxygen in the blood
Hemoglobin (Hb)
what is hemoglobin saturation
percentage of heme units containing bound oxygen
what affects saturation
partial pressures of oxygen
if Hb is exposed to pressure O2 above 60mm HG then it will be ____ saturated
90% saturated
O2 is bound to ____ions in the center of the heme units of hemoglobin (Hb)
iron ions
How is CO2 generated
by aerobic metabolism in tissues
3 things CO2 does after it enters the bloodstream
- converted to carbonic acid molecule (Most CO2 does this)
or - bound to protein portion of Hb in RBC (93%)
or - dissolved in plasma (small amnt ~7%)
ALL OF THESE ARE REVERSIBLE
percentange of CO2 that diffuses into RBC when P CO2 is 45mmHg
93%
Partial pressure of a gas (P) is
pressure that specific gas exerts in a mixture of gases
Daltons law
all partial pressures added Tg = total pressure exerted by gas mixture
Henrys law
at a given temp, amount of gas in a solution is proportional to its partial pressure
does the characteristics of air change as it passes through respiratory system??
yes it does
partial pressure of O2 in inhaled air (dry)
159 (20.9%)
partial pressure of O2 in alveolar air (saturated)
100 (13.2%)
partial pressure of O2 in exhaled air (saturated)
116 (15.3%)
partial pressure of CO2 in inhaled air (dry)
0.3 (0.04%)
partial pressure of CO2 in alveolar air (saturated)
40 (5.2%)
partial pressure of CO2 in exhaled air (saturated)
28 (3.7%)
pulmonary ventilation respiratory rate
12-18 breaths per min is normal
pulmonary ventilation respiratory minute volume
is the volume of air moved each minute
tidal volume x resp. rate
what are the factors the affect respiratory minute volume (pulmonary ventilation)
- respiratory rate
- tidal volume
Alveolar ventilation
the. amount of air reaching the alveoli each minute or the movement of air into + out of the alveolis
breaths per min x (respiratory minute volume)
do all of the inhaled air reach the alveolis?
nope not all
anatomical dead space
air that fills the conducting division and cant exchange gases with blood (~150 to 500 mL inhaled)
- never reaches alveoli’s
- some alveolis may be unable to exchange gases
physiological dead space is the sum of
anatomical dead space + alveolar dead space
muscles involved in inspiration (inhaling)
external intercostals
diaphragm
muscles involved in forced expiration (exhaling)
internal intercostals
abdominal muscles (rectus abdomini)
- the diaphragm relaxes during this
tidal volume
amount of air inhaled/exhaled with each breath under resting conditions
inspiratory reserve volume (IRV)
amount of air that can be forcefully inhaled after normal tidal volume inspiration
expiratory reserve volume (ERV)
amount of air that can be forcefully exhaled after a normal tidal volume expiration
residual volume (RV)
amount of air remaining in the lungs after a forced expiration
total lung capacity (TLC)
max. amount of air contained in lungs after max inspiratory effort
vital capacity (VC)
max amount of air that can be expired after max inspiratory effort
TV adult male average and female average
500mL for both male + fem.
IRV adult male average and female average
adult male average - 3100mL
adult female average - 1900mL
ERV adult male average and female average
adult male average - 1200mL
adult female average - 700mL
RV adult male average and female average
adult male average - 1200mL
adult female average - 1100mL
TLC adult male average and female average
adult male average - 6000mL
adult female average - 4200mL
VC adult male average and female average
adult male average - 4800mL
adult female average -3100mL
Sequence of the structures air/oxygen passes through
1st there’s airflow through conducting division - nasal cavity then to pharynx - larynx - trachea - main bronchus - bronchiole - terminal bronchiole
then it goes through the resp. division
- resp. bronchioles - alveolar duct - alveolus
attachments of vocal cords and
attachments on vocal cords are intristic muscles include thyroid and cricoid cartilage , vestibular fold and glottis
which attachment plays a big role in controlling sound pitch
cricoid cartilage
but all attachments do
adduction of vocal cords
allows for sound to be produces because vocal folds vibrate tg
faster vibration = higher pitch
abduction of vocal cords
vocal folds move far away allowing for breathing
Right lung
- shorter and wider because the liver takes up more space
- has 3 lobes (superior, middle,inferior)
- 2 fissures (oblique and horizontal)
Left lung
-narrow and larger because of the heart
- 2 lobes (superior and inferior)
- has only the iblique fissure
- has the cardiac notch
what is the structure in the lungs in which things go in and out (such as the vessels and bronchis)??
hilum
what are the two alveolar cells that cover the alveolus
- squamos alveolar cells
- great alveolar cells
describe squamos alveolar cells + functions
type I pneumocytes
- makes up 95% of alveolar surface area
- its thin which allows for rapid gas exchange
describe great alveolar cells + functions
type II pneumocytes
- repairs damaged alveolar epithelium
- secretes pulmonary surfactant (soapy texture to prevent the aveolis from closing tg)
how big is the alveolus
.2-.5mm and it is a tiny pouch covered with 2 cells
where is the respiratory membrane?
barrier between alveolar air and blood of surrounding capillary
- simple squamos cell and capillaries simple squamos
boyles law
pressure of a given quantity of gas is inversely proportional to its volume
(boyle) as pressure decreases
volume increases
as pressure increases
volume decreases
what drive respiration?
(mainly atmospheric pressure) and intrapulmonary pressure and its change in lung volume
when intrapulmonary falls below atmospheric pressure air flows where?
into lungs (inspiration)
if intrapulmonary pressure rises above atmospheric pressure, air flows where?
out (expiration)
if you decrease volume of thoracic cavity then lung pressure ??
increases
what happens during inspiration
- thoracic cavity expands laterally, vertically, + anteriorly
- intrapulmonary pressure drops
- air flows into lungs
what happens during expiration
- thoracic cavity constricts in all 3 directions
- intrapulmonary pressure rises
- air flows out of lungs
external respiration
includes all processes involved in the exchange of O2 and CO2 between the body’s interstital fluids + external environment.
- purpose and function of this is meeting respiratory demands of cells
what is internal respiration
absorption of O2 + the released of CO2 by tissue cells
pulmonary ventilation or breathing
involves physical movement of air into + out of the lungs
- primary function is to maintain adequate alveolar ventilation
what does Alveolar ventilation prevent?
prevents the build up of CO2 in the alveoli + ensures continous supply of O2 that keeps pace with absorption by bloodstream
where does gas diffusion occur
across the respiratory membrane between alveoli + capillaries. and across capillary walls between blood + other tissues
