mc Flashcards
For active expiration, which occurs first?
A. air flows out of the lungs
B. thoracic volume decreases
C. alveolar pressure becomes greater than atmospheric
D. expiratory muscles contract
d.expiratory muscles contract
At rest, what is the normal carbon dioxide partial pressure (Pco2) in the pulmonary artery of a healthy
person?
A. 40 mm Hg
B. 46 mm Hg
C. 100 mm Hg
D. 150 mm Hg
B. 46 mm Hg
Which value is about the same in both the pulmonary and systemic circulations?
A. total blood flow per minute
B. vascular resistance
C. arterial pressure
a. total blood flow per minute
Which part of the brain is most important in determining the respiratory pattern for a person that is doing spirometric measurements like a forced vital capacity?
A. cerebral cortex
B. subcortical regions
C. medulla oblongata
D. pons
a. cerebral cortex
Expiration of alveolar gas:
A. is typically active.
B. can follow contraction of the expiratory muscles.
C. occurs when alveolar pressure is less than atmospheric pressure.
D. occurs as the lung volume increases.
B. can follow contraction of the expiratory muscles
Loretta breathes 10 times per minute; her tidal volume is 600 ml and her anatomic dead space is 300
ml. What is her alveolar ventilation?
A. 6000 ml/min
B. 4000 ml/min
C. 3000 ml/min
D. 2000 ml/min
C. 3000 ml/min
The volume of air inhaled between the FRC (functional residual capacity) and a maximal inspiration is the:
A. inspiratory capacity
B. tidal volume
C. inspiratory reserve volume
D. residual volume
a. inspiratory capacity
Emphysema, a pulmonary blood clot, and lung cancer are all likely to:
A. increase the lung compliance.
B. decrease the work of breathing.
C. decrease the surface area for gas exchange.
D. increase the PAO2 in the alveolar gas
d. decrease the surface area for gas exchange
Hemoglobin in systemic arterial blood is usually described as:
A. fully saturated with oxygen.
B. deoxyhemoglobin
C. 2,3 - BPG
D. having 2 alpha- and 2 gamma- chains
a. fully saturated with oxygen
The oxygen-hemoglobin dissociation curve:
A. has an steep portion that facilitates O2 unloading in the lungs
B. has a plateau portion that facilitates O2 loading in the lungs
C. has a vertical axis (Y axis) that depicts the Partial pressure of oxygen
D. is linear (a straight line) because of the interaction of the 4 heme centers.
b. has a plateau portion that facilitates o2 loading in the lungs
The oxygen-hemoglobin dissociation curve is shifted rightward by increasing which property in the blood?
A. 2,3-DPG (BPG) content
B. PO2
C. hematocrit
D. pH
a. 2,3-BPG content
The majority (70%) of CO2 in blood is transported in what form?
A. carbaminohemoglobin
B. dissolved CO2
C. H2CO3
D. HCO3-
d. HCO3-
When a patient secretes large amounts of mucus into the airways, you would expect the mucus to
__________ the lumen of the conducting zone, ______ the resistance to airflow, and _____the volume of
the dead space.
A. enlarge; decrease; increase
B. narrow; decrease; increase
C. enlarge; increase; decrease
D. narrow; increase; decrease
D. narrow; increase; decrease
Which aspect of blood chemistry elicits the greatest increase in activity of the peripheral
chemoreceptors?
A. systemic arterial pH of 7.4
B. oxyhemoglobin saturation of 90%
C. venous PCO2 of 46 mmHg
D. arterial Po2 less than 60 mmHg
arterial Po2 less than 60mmHg
When one visits a region at high altitudes (e.g., the Peruvian Andes), what is the primary sensed
variable that leads to an increase in one’s minute ventilation?
A. systemic arterial PO2
B. systemic arterial PCO2
C. systemic venous pH
D. CSF pH
a. systemic arterial PO2
What causes the partial lung collapse in a person that has pneumonia?
A. lung volume increases
B. transpulmonary pressure decreases
C. intrapleural pressure in the affected region becomes more negative
b. transpulmonary pressure decreases
Which cell type is most likely to be abnormal in a prematurely born infant?
A. alveolar type I cells
B. alveolar type II cells
C. alveolar macrophages
D. white blood cells
b. alveolar type II cells
Which brain region is most important in altering your breathing while watching a basketball game?
A. medulla oblongata
B. cerebral cortex
C. pons
D. subcortical regions
d. subcortical regions
Gas exchange across your lungs may be reduced by:
A. increased surface area
B. congestive heart failure
C. decreased dead space
D. all of the above
b. CHF
Pulmonary surfactant:
A. increases lung compliance
B. increases surface tension
C. is more effective as alveolar radius increases
D. is secreted by alveolar type I cells
a. inc lung compliance
The pressure difference between the pressures in the atmosphere and in the alveoli is equal to:
A. pressure divided by flow
B. flow times resistance
C. volume times pressure
b. FLOW x RESISTANCE
What is the total body water weight in a 100-pound female?
20 pounds
40 pounds
60 pounds
80 pounds
60 lbs
An increase in ________ activity causes contraction of the detrusor (bladder) muscle.
sympathetic
parasympathetic
somatic motor
parasympathetic
Relaxation of this muscle in the urinary system is under voluntary control.
A. smooth muscle of the ureters
B. smooth muscle of the urethra
C. internal urethral sphincter
D. external urethral sphincter
E. detrusor muscle
d. external urethral sphincter
Which of the following two scenarios would each predict an INCREASE in Glomerular
Filtration Rate (GFR)?
A. vasoconstriction of the afferent arteriole OR vasoconstriction of the efferent arteriole
B. vasoconstriction of the afferent arteriole OR vasodilation of the efferent arteriole
C. vasodilation of the afferent arteriole OR vasoconstriction of the efferent arteriole
D. vasodilation of the afferent arteriole OR vasodilation of the efferent arteriole
C. vasodilation of the afferent arteriole OR vasoconstriction of the efferent arteriole
The sequential order of the blood flow through the nephron is best described as:
A. afferent arteriole- peritubular capillaries- efferent arteriole- glomerular capillaries
B. efferent arteriole- peritubular capillaries- afferent arteriole- glomerular capillaries
C. afferent arteriole- glomerular capillaries- peritubular capillaries- efferent arteriole
D. afferent arteriole- glomerular capillaries- efferent arteriole- peritubular capillaries
D. afferent arteriole- glomerular capillaries- efferent arteriole- peritubular capillaries
If a substance is filtered, secreted and completely reabsorbed in the nephron, how much is
excreted?
A. nothing
B. everything that is filtered but not secreted
C. everything that is secreted but not filtered
D. everything
a. nothing
Which of the following substances is normally filtered in the glomerular capsule?
A. red blood cells
B. plasma proteins
C. molecules > 5000 daltons
D. bacteria
E. glucose
E. glucose
A decrease in the osmotic force due to protein in the plasma will ________ the glomerular
filtration rate.
A. increase
B. decrease
C. not change
a. increase
the kidneys maintain a constant GFR despite systemic changes. If the mean arteriole pressure
drops below 70 mm Hg which of the following is most likely to occur?
A. vasodilation of the afferent arteriole
B. vasoconstriction of the afferent arteriole
C. vasodilation of the efferent arteriole
D. vasoconstriction of the afferent arteriole and efferent arteriole
a. vasodilation of the afferent arteriole
A person who has renal failure most likely has
A. hypokalemia (abnormally low concentration of K+ in plasma)
B. high plasma concentration of creatinine
C. low mean arterial pressure
D. high levels of erythropoietin
B. high plasma concentration of creatinine
Which of the following is TRUE about juxtamedullary nephrons?
A. they originate in outer 2/3 rd of the renal cortex
B. they have relatively short loops of Henle
C. they are critical for producing hypertonic urine
D. they comprise ~80% of the nephrons in the human kidney
C. they are critical for producing hypertonic urine
The juxtaglomerular apparatus consists of macula densa and granular cells. If plasma Na+
concentration is high then the release of ______ from granular cells will decrease.
A. antidiuretic hormone
B. aldosterone
C. angiotensinogen
D. renin
E. angiotensin II
d. renin
which one of the following statements about inulin clearance is TRUE?
A. it is typically greater than the GFR
B. it is always less than GFR
C. it is similar to the clearance of creatinine
D. it is normally greater than the clearance of aminohippuric acid (PAH)
C. it is similar to the clearance of creatinine
Urea clearance is normally ______ the glomerular filtration rate (GFR).
a. less than
B. greater than
C. equal to
a. less than
If the renal transport threshold for glucose is reached that means glucose _____ will
increase.
A. filtration
B. reabsorption
C. secretion
D. excretion
d. excretion
A person with Conn’s disease has an abnormally high level of aldosterone. The urine of this
person most likely has lower than normal concentration of
A. Na+
B. H 2 PO 4
C. NH 4 +
D. K
A. Na+
A person with Addison’s disease has very low levels of aldosterone. The plasma of this
person most likely has higher than normal concentration of
A. K+
B. HCO 3 -
C. Na+
a. K+
person with altitude sickness (which causes hyperventilation) might benefit from which of
the following diuretics?
A. loop
B. thiazide
C. osmotic
D. carbonic anhydrase inhibitors
E. potassium sparing
D. carbonic anhydrase inhibitors
the osmolarity of the ultrafiltrate decreases in this part of the nephron due to the
reabsorption of Na+, K+ and Cl- and impermeability to water
loop of henle ascending
The ultrafiltrate is formed at this part of the nephron.
Glomerular capsule aka Bowmans
A decrease in antidiuretic hormone (ADH) signaling decreases water reabsorption at this part
of the nephron
CD
About 90% of the filtered K+ is reabsorbed at this part of the nephron
PCT
About 40-60% of urea is reabsorbed at this part of the nephron
CD (MEDULLARY)
This portion the nephron is permeable to water but not Na+, K+, or Cl-.
descending limb LOH
Most of the reabsorption of filtered Na+ occurs in this part of the nephron
PCT
A decrease in ADH signaling _____ water reabsorption in the _______
decreases, medullary collecting duct
t/f Secretion is the process of moving substances from the blood into the nephron
tubule lumen
true
An increase in aldosterone would result in
decreased NaCl excretion
What is the tonicity of the filtrate in at the end of the proximal convoluted tubule
(PCT)
isotonic (~ 300 mOsm)
Air flows out of the lung when the intrapulmonary pressure is _____ then the
atmospheric pressure
greater than
With lung expansion, the intrapulmonary pressure ______ atmospheric pressure.
20 sec
increases above
falls below
equilibrates
falls below
During expiration the alveolar pressure is ____ than the atmospheric pressure.
20 sec
greater than
less than
equal to
greater than
At rest, the intrapulmonary pressure is always ______ the atmospheric pressure.
20 sec
greater than
less than
equal to
equal to
Activation of pulmonary (stretch) receptors will _____ inspiration.
20 sec
inhibit
stimulate
inhibit
A right shift in the oxyhemoglobin dissociation curve means…
20 sec
the oxygen affinity of hemoglobin is reduced
the oxygen affinity of hemoglobin is increased
hemoglobin saturation goes above 100%
oxygen cannot bind to hemoglobin
the oxygen affinity of hemoglobin is reduced
Intrapulmonary at rest=
760 mmHg
Intrapleural at rest=
756 mmHg
Compliance =
change in V/ change in P
partial pressure= % in decimal x
760 (atmospheric pressure)
minute ventilation=
Resp frequency x Tidal Volume
Alveolar ventilation=
Resp frequency (Tidal volume- anatomic dead space)
