Respiratory System Flashcards
The relaxation and dilation of the upper airways is a function of the ___________ (sympathetic or parasympathetic) branch of the autonomic nervous system, mediated by ___________ (neurotransmitter) binding to ___________ (receptor type) receptors.
sympathetic, epinephrine/norepinephrine, adrenergic (β2)
___________ is the medical term for the total rate of air movement into and out of the lungs.
ventilation
___________ law states that the product of pressure and volume is constant, a relationship that helps explain how pressure changes in the lungs drive breathing.
Boyle’s
___________ volume refers to the volume of air breathed in and out during a normal breath, while ___________ volume represents the additional volume of air that can be forcibly inhaled after a normal inhalation.
Tidal, inspiratory reserve
The majority of gas exchange occurs in the ________.
alveolar sacs
Smoking affects the ______ lobes of the lung the most.
upper
The ___________ are tiny sacs in the lungs where gas exchange takes place, primarily mediated by ___________ cells.
alveoli, Type I
While Type I alveolar cells are primarily responsible for gas exchange, ___________ cells within the alveoli are crucial for fluid reabsorption and the secretion of ___________, a substance that reduces surface tension and prevents alveolar collapse.
Type II, surfactant
True or False: sympathetic innervation of the airways leads to dilation.
True
Albuterol acts at _____ receptors.
Beta-2
True or False: The back of the trachea has collagen rings.
False (C-shape allows for both expansion of trachea and protection)
___________ refers to the total volume of the lung that does not participate in gas exchange, including the anatomical dead space of the conducting airways and any alveolar volume that is not adequately perfused.
Physiologic dead space
The conducting zone consists of: ________
Trachea, bronchi
True or False: No gas exchange occurs in the conducting zone.
True
The forced expiratory volume in 1 second (FEV1) divided by the forced vital capacity (FVC) is approximately ___________ in healthy individuals, and a value below this threshold suggests ___________.
0.8, obstructive lung disease
Increase the velocity of air may aid in _______.
coughing
Bronchioles, unlike the alveoli, primarily engage in fluid ___________ (secretion or reabsorption), driven by the movement of ___________ ions through epithelial cell ___________ channels.
secretion, Cl-, CFTR
The aqueous layer on top of the luminal layer of the alveolar cells is very ______.
thin
CFTR stands for _______.
Cystic Fibrosis Transmembrane Conductance Regulator
In the context of pulmonary physiology, ___________ refers to the process of air reaching the alveoli, while ___________ refers to the blood flow in pulmonary capillaries that allows for gas exchange.
ventilation, perfusion
The partial pressure of oxygen (PaO2) in arterial blood is typically ___________ (higher or lower) than the partial pressure of oxygen in the alveoli (PAO2).
lower
An increase in the physiological dead space will ___________ (increase or decrease) the efficiency of gas exchange in the lungs.
decrease
During exercise, alveolar ventilation ___________ (increases or decreases) to meet the increased demand for oxygen uptake and carbon dioxide removal.
increases
The shape of alveolar Type I cells is _______, while Type II is more _______.
squamous, cuboidal
Normal breathing is referred to as _____.
tidal volume (TV)
Vital capacity is ______.
The summation of IRV and ERV.
FEV1 is the amount of air able to be _______ in one second.
expired
True or False: residual volume is able to be measured by simple spirometer.
False, you can’t get all the air out of your lungs because they will collapse
Constriction of the bronchioles, as seen in asthma, primarily affects ___________ (airway resistance or lung compliance) and leads to ___________ (increased or decreased) airflow.
airway resistance, decreased
The volume of air remaining in the lungs after a maximal exhalation is called the ___________.
residual volume
Common way of measuring RV nowadays is _____.
helium dilution
Average total ventilation for an adult is _____ ml/min.
7500
Average alveolar ventilation for an adult is ______ ml/min.
5250
Minute ventilation is tidal volume x _________.
breaths per minute
Inspired air is approximately ______ mmHg.
150
Mixed venous blood has (in terms of partial pressure) approximately ______ mmHg oxygen and ______ mmHg CO2.
40, 46
Horseshoe crabs have ______ instead of iron in the middle of hemoglobin.
copper
The byproduct of RBC glycolysis that affects oxygen dissociation is ________.
23DPG
The metal ion at the center of the heme group in hemoglobin is ______.
Iron (Fe)
The effect that describes the influence of pH and CO2 on oxygen binding to hemoglobin is the __________.
Bohr Effect
The effect that describes the influence of oxygen on CO2 binding to hemoglobin is the _________.
Haldane Effect
The approximate percentage of oxygen transported in the blood that is dissolved in plasma is _______.
15
The protein responsible for the majority of oxygen transport in the blood is __________.
hemoglobin
One molecule of hemoglobin can bind _____ oxygen molecules.
4
The condition where the iron in hemoglobin is oxidized to Fe3+ and cannot bind oxygen is ____________.
Methemoglobinemia
The partial pressure of oxygen PO2 in arterial blood is approximately ________.
100 mmHg
The partial pressure of oxygen PO2 in mixed venous blood is approximately _________.
40 mmHg
The approximate oxygen saturation of arterial blood is _____.
98
The approximate oxygen saturation of mixed venous blood is _____.
75
The graph that shows the relationship between oxygen partial pressure and hemoglobin saturation is the _____________.
Oxygenhemoglobin dissociation curve
The shape of the oxygen-hemoglobin dissociation curve is ________.
Sigmoidal
A rightward shift of the oxygen-hemoglobin dissociation curve is caused by ___________.
Increased temperature, Increased PCO2, Increased 23DPG, Decreased pH
A leftward shift of the oxygen-hemoglobin dissociation curve is caused by ____________.
Decreased temperature, Decreased PCO2, Decreased 23DPG, Increased pH
The P50 value is ______________.
The partial pressure of oxygen at which hemoglobin is 50 saturated
The effect of increased 23DPG on oxygen affinity of hemoglobin is ____________.
Decreased affinity
Conditions that can lead to increased 23DPG levels are ________.
Hypoxia, High altitude
Fetal hemoglobin differs from adult hemoglobin in terms of 23DPG binding because _____________.
Fetal hemoglobin binds 23DPG less avidly
The approximate affinity of carbon monoxide CO for hemoglobin compared to oxygen is _______________.
250 times greater
The molecule formed when carbon monoxide binds to hemoglobin is __________.
Carboxyhemoglobin
The effect of carbon monoxide binding on the oxygen-hemoglobin dissociation curve is _________.
Leftward shift making it harder to unload oxygen
The term for insufficient oxygen supply to tissues is ________.
hypoxia
The transcription factor that is activated in response to hypoxia is _____________.
Hypoxiainducible factor 1a (HIF1a)
The hormone stimulated by HIF1a to increase red blood cell production is ___________.
Erythropoietin EPO
Erythropoietin EPO is produced in the __________.
kidneys
The main form in which CO2 is transported in the blood is __________.
Bicarbonate (HCO3)
The enzyme that catalyzes the conversion of CO2 and water to carbonic acid is ________.
Carbonic anhydrase
The membrane protein that exchanges bicarbonate for chloride ions across the red blood cell membrane is _________.
Anion exchanger 1 (AE1) or Chloride-bicarbonate exchanger
The effect the binding of oxygen to hemoglobin has on CO2 transport Haldane effect is ____________.
It promotes the release of CO2 from hemoglobin
The effect the binding of CO2 to hemoglobin has on oxygen transport Bohr effect is ___________.
It promotes the release of oxygen from hemoglobin
During exercise, the oxygen-hemoglobin dissociation curve shifts __________.
rightward
At high altitude, the oxygen-hemoglobin dissociation curve shifts ___________.
rightward
The effect of exercise on oxygen consumption is _____________.
increased oxygen consumption
The effect of high altitude on oxygen availability is ___________.
decreased oxygen availability
The main physiological adaptations to high altitude are __________.
Increased ventilation, Increased red blood cell production, Increased 23DPG levels
The primary function of the respiratory system is ____________.
Gas exchange: oxygen uptake and carbon dioxide removal
The two main components of the respiratory system are _________ and _______.
lungs, airways
The tiny air sacs in the lungs where gas exchange occurs are the __________.
alveoli
The muscle that separates the thoracic cavity from the abdominal cavity and is involved in breathing is the ________.
diaphragm
During inhalation, the volume of the thoracic cavity _________.
increases
During inhalation, the pressure in the thoracic cavity ________.
decreases
The law that describes the relationship between pressure and volume of a gas is _________.
Boyle’s law
The pressure gradient that drives oxygen from the alveoli into the blood is the ______________.
partial pressure gradient
The pressure gradient that drives carbon dioxide from the blood into the alveoli is the ______________.
partial pressure gradient
The typical breathing rate at rest is ___________.
1220 breaths per minute
The condition where breathing is difficult or labored is _______________.
dyspnea
The condition where breathing stops temporarily during sleep is _______________.
sleep apnea
The most common expressed protein in a red blood cell is __________, which is “band 3” on a western blot.
AE1
True or False: Carbon dioxide and water going bicarb and protons always requires carbonic anhydrase.
False
What are the four components of the respiratory control system?
- Chemoreceptors, 2. Mechanoreceptors, 3. Brain Stem (medulla & pons), 4. Respiratory muscles
What part of the brain provides voluntary control of respiration?
Cerebral Cortex (But, ‘overruled’ by Brain Stem)
What is apneusis?
Sustained effort for inhalation unrelieved by exhalation
True or False: The pons is the most essential portion of the brain needed for respiration.
False, it’s the medulla
What is the function of the pneumotaxic center?
Sends inhibitory impulses on inspiration, preventing overdistension of the lungs
Smooth, steady inspiration due to ramp signals allows for _________(less/more) work by the respiratory system.
Less, smaller pressure gradient
True or False: Smooth, steady expiration prevents the lungs from collapsing.
True
What nerve innervates the diaphragm?
Phrenic nerve
What nerve innervates the tongue muscles (except palatoglossus)?
Hypoglossal nerve
Describe the diaphragm’s electroneurographic activity during normal inspiration.
Begins weakly and increases steadily in a ramp manner for about 2 seconds.
What is the primary method for controlling the rate of respiration?
Changing the rate of increase of the ramp signal in the diaphragm
What is the function of the inspiratory “off-switch” signal?
Offsets the large elastic recoil of the lungs at the end of inspiration
True or False: Central chemoreceptors directly measure Pco2.
False, they measure it indirectly by measuring pH (H+ ions)
Define eupnea
Normal, good, unlabored ventilation
Describe the breathing pattern in apneustic breathing.
Protracted gasping inhalation followed by short, inefficient exhalation