exam 3 Flashcards
upper respiratory tract includes
nose, pharynx, larynx
lower respiratory tract includes
larynx, trachea, bronchi and lungs.
brings air to/from the site of gas
exchange (external respiration): nose, pharynx, larynx,
trachea, bronchi, bronchioles and terminal
bronchioles
conducting zone:
main site of gas exchange : respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.
respiratory zone :
Air passing through the respiratory
tract traverses the (the order)
Nasal cavity
Pharynx
Larynx
Trachea
Primary (1o) bronchi
Secondary (2o) bronchi
Tertiary (3o) bronchi
Bronchioles
Alveoli (150 million/lung)
nose is visible on the face
external
nose is the cavity beyond the nasal vestibule.
divided by nasal septum
internal
Function of what? :
Filter, warm, moisten incoming air
Smell incoming air
Resonating chamber
nose
Three _______: protrude from each
lateral wall.
nasal conchae (or turbinates)
function of :
Meatus under each nasal concha, for a duct that drains secretions of the sinuses and tears into the nose.
Increases turbulence mixing air for moisture
and warmth
the nasal conchae
hollow tube starting posterior to the nasal
cavity and descending to the opening of the larynx in the neck
Pharynx
Function of what? :
o a passageway for air and food
o a resonating chamber
o a housing for the tonsils
Pharynx
3 anatomical regions of pharynx
The nasopharynx; oropharynx; and laryngopharynx
Most of the Respiratory tract is lined with
ciliated pseudostratified columnar tissue
_____ moves mucous and trapped particles toward the pharynx and into the digestive tract.
cilia
_____ is composed of 9 pieces of cartilage: connects the laryngopharynx with the trachea (the “windpipe”).
Larynx
- prevents food and water from entering
the lower respiratory system - Resonating chamber
Larynx
flap of elastic cartilage covered with a mucus membrane, attached to the root of the tongue
Epiglottis
epiglottis guards the entrance of the____, the
opening between the vocal folds.
glottis
As air passes from the _____ into the _____, it
leaves the upper respiratory tract and enters the lower respiratory tract.
laryngopharynx, larynx
semi-rigid pipe of semi-circular cartilaginous
rings, anterior to the esophagus. Extends from the larynx into the mediastinum where it divides into right and left primary (1o, “mainstem”) bronchi.
trachea
The trachea is composed of 4 layers:
a mucous secreting epithelium: mucosa
three layers of CT (submucosa, hyaline cartilage, and adventitia).
Tracheal cartilage rings are incomplete (anterioirly/posteriorly), facing the esophagus.
posteriorly
Esophageal masses can press into this _______ and make it difficult to breath, or even totally obstruct the airway.
soft part of the trachea
emerge from the inferior trachea at the carina
go to the lungs, situated in the right and left pleural cavities
Primary (1o or “mainstem”) bronchi
____ bronchi divide into bronchioles
3
1o bronchi divide to form 2o (_____) and 3o bronchi (_____) of each lung
supply lobes, supply segments
bronchioles
o branch through
about 22 more divisions
o The smallest are the
terminal bronchioles
As bronchi and bronchioles branch and become smaller.
mucous membrane changes from _____
columnar to cuboidal
As bronchi and bronchioles branch and become smaller.
cartilaginous rings become _____
more sparse, and eventually disappear altogether.
In bronchioles, smooth muscle
increases
smooth muscle Sympathetic stimulation:
airway dilation
smooth muscle Parasympathetic stimulation:
airway constriction
trachea to the terminal bronchioles: conducting airways –
they do not participate in gas exchange.
participates in gas exchange
Alveoli
Alveoli
Connected to respiratory bronchioles (_____) and alveolar ducts (_____)
simple cuboidal epithelium. Simple squamous
alveoli, alveolar sacs, respiratory bronchioles, alveolar ducts and a terminal bronchiole
Pulmonary lobule
is wrapped in elastic CT
Pulmonary lobule
composed chiefly of type I alveolar cells,
allowing for exchange of gases with
pulmonary capillaries.
Alveoli
secrete surfactant that prevents collapse of the alveoli during exhalation.
Alveoli macrophages remove microscopic debris
Type II cells
a substance which tends to reduce the surface tension of a liquid in which it is dissolved.
surfactant
The lungs receive blood via two sets of arteries
pulmonary arteries and Bronchial arteries
carry deoxygenated blood from the
right heart to the lungs for oxygenation
pulmonary arteries
branch from the aorta and deliver
oxygenated blood to the lungs (primarily the muscular walls of the bronchi and bronchioles)
Bronchial arteries
matches perfusion (blood flow) of areas in the lungs to ventilation (airflow) in that area
Ventilation-perfusion coupling:
which lung has three lobes and two lobes
right=3, left=2
superior, extends slightly above the
clavicles
Apex of the lung
on the diaphragm
Base of the lung
(indentation for the heart) makes the left
lung slightly smaller than the right lung
Cardiac notch –
line the walls of the thoracic cavity
parietal pleura
adhere tightly to the lungs
visceral pleura
On each side of the thorax, a _____ is formed
pleural cavity
surface tension moves two
layers together
Mechanical coupling:
The gases of the atmosphere have a____ and a_____ (5 x 1018 kg)
mass. weight
the atmosphere exerts a significant_____ on every object on the planet through _____ (force applied per unit area, P = F/A.)
Measured by a_____
force. air pressure. barometer
At sea level, the air pressure is:
760 mmHg = 1 atmosphere
At high altitudes, the atmospheric pressure is (greater/less);
descending to sea level, atmospheric pressure is (greater/less).
less. greater
apply equally to the gases of the atmosphere, the gases in our lungs, the gases dissolved in the blood, and the gases diffusing into and out of the cells of our body.
gas laws
______common gas laws are important to the mechanics of ventilation and respiration
3 of the 5
applies to containers with flexible walls – like
our thoracic cage
Boyle’s law
Volume and pressure are ______.
o If there is a____ in volume – there will be an_____ in pressure.
o V ∝ 1/P
inversely related. decrease. increase
applies to a mixture of gases.
Daltons law
The pressure of each gas is directly proportional to the percentage of that gas in the total mixture:
PTotal = P1 + P2 + P3 …
O2 = 21% of atmosphere, the partial pressure exerted by the contribution of just O2 (written pO2 or PAO2) = 0.21 x 760 mmHg = 159.6 mmHg at sea level.
just read
gas molecules diffuse from regions of higher pressure (higher concentration) to regions of lower pressure (lower concentration)
gas exchange - partial pressure (just read)
deals with gases and solutions
henrys law
movement of air between the atmosphere and the alveoli: inhalation and exhalation.
ventilation
ventilation is made possible by
changes in the intrathoracic volume
Respiration is the
exchange of gases
gas exchange between the alveoli and the blood.
External respiration (pulmonary
gas exchange between the systemic capillaries and the tissues of the body
Internal respiration (tissue)
Changing the volume of the thoracic cavity (and the lungs – remember the mechanical coupling of the chest wall, pleura, and lungs),
changes the pressure in the lungs
Changes in air pressure result in
movement of the air
Gas will always move from a region of____ pressure to a region of____ pressure.
high. low
primary muscle of respiration – all the
others are accessory.
diaphragm
The recruitment of accessory muscles greatly depends on whether the respiratory movements are quiet (______), or forced (____-).
normal. labored
3 other factors also affect the ease with which we ventilate:
surface tension of alveolar fluid, lung compliance, and diameter of an airway
accounts for 2/3 of lung elastic recoil. Surfactant prevents the complete collapse of alveoli at exhalation, facilitating reasonable
levels of work
surface tension of alveolar fluid
means the lungs and chest wall expand easily.
Lung compliance
______diameter of an airway-> less airway
resistance->greater flow of air
Larger
Ventilation can be measured using
spirometry
is the volume of air inspired (or expired) during normal quiet breathing (500 ml).
Tidal Volume
is the volume inspired during a very deep inhalation (3100 ml – height and gender dependent)
inspiratory Reserve Volume (IRV)
is the volume expired during a forced exhalation (1200 ml)
Expiratory Reserve Volume (ERV)
is all the air that can be exhaled after
maximum inspiration
Vital Capacity (VC)
______ s the sum of the inspiratory reserve + tidal volume + expiratory reserve (4800 ml)
Vital Capacity (VC)
is the air still present in the lungs after a force exhalation (1200 ml).
Residual Volume (RV)
The RV is a reserve for mixing of gases but (is/is not) available to move in or out of the lungs.
is not
About 70% of the tidal volume reaches the _____ zone – the other 30% remains in the ____ zone (called the _____)
respiratory. conducting. anatomic dead space
The pressure of a specific gas is the partial
pressure Pp.
Atmospheric pressure
(760 mmHg) =
Since O2 is 21%
PO2 =760 x 0.21 =
159.6 mmHg.
daltons law
Gas ______ (like the AC membrane) from greater partial pressure to lower partial pressure
diffuses across a permeable membrane
_____ the difference=faster diffusion
Greater
O2 moves from the _____ into the blood
alveoli
___ moves into the lungs
CO2
In the blood, a tiny amount of O2 is dissolved in the plasma. Most O2 (about 98.5%) is carried attached to Hb.
Oxygenated Hb is called _____
oxyhemoglobin
CO2 is transported in the blood in three different forms:
gas, carbonic acid/bicarbonate, Hb
7% is dissolved in the plasma, as a
gas
70% is converted into ______ catalyzed by the enzyme carbonic anhydrase.
o CO2 + H2O H2CO3 H+ + HCO3-
carbonic acid/bicarbonate
23% is attached to ____ (but not at the same binding sites as oxygen)
Hb
The amount of Hb saturated with O2 is called the
SaO2
The relationship between the pressure of O2 in the plasma and the saturation of Hb
Oxygen-hemoglobin saturation curve
The higher the ___ dissolved in the plasma,
the higher the ___.
PO2. SaO2
_____ shift the entire O2 –Hb saturation
curve to the right (lower affinity for O2)
Acidity (pH), PCO2, and blood temperature
Fever (^ temp.) , ^ CO2, and acidosis (^ H+ ) shift ______, making it easier to unload O2 at the tissues
* Hypothermia ( ↓temp.), ↓CO2, and alkalosis,
(↓H+ ) shift _____, binding 02 more strongly
the curve to the right. the curve to the left
Fetal hemoglobin (Hb-F) has a (lower/higher) affinity for oxygen (it is shifted to the left) than adult hemoglobin A, so it binds O2 more strongly
higher
located in the brainstem, has centers that control basic respiratory patterns for both inspiration and expiration.
Medulla rhythmicity area:
Other sites in the____ help the medullary centers manage the transition between inhalation and exhalation.
pons
voluntary control of breathing.
cortex
Stretch receptors sensing over-inflation arrests
breathing temporarily
(Herring Breuer reflex)
(limbic system) affect respiration
emotions
The_____, sensing a fever, increases
breathing, as does moderate pain
hypothalamus
_____ (pH*, O2 too low, CO2 too high)
increases breathing *primary signal
Blood Chemistry
