McqMate
Chapters
| 601. |
Regarding renal tubular function: |
| A. | Na+ is actively transported out of the thin portions of the loop of Henle |
| B. | Na+ -K+ ATPase pumps Na+ out of the renal tubule |
| C. | Cl- is transported only by co-transport |
| D. | glucose is reabsorbed mainly in the distal tubule |
| E. | penicillin is not actively secreted into tubular fluid |
| Answer» B. Na+ -K+ ATPase pumps Na+ out of the renal tubule | |
| 602. |
Regarding the actions of angiotensin II, which is INCORRECT? |
| A. | selective renal efferent arteriolar constriction |
| B. | acts on CNS without crossing blood-brain barrier |
| C. | contract mesangial cells |
| D. | direct positive chronotropic action on heart |
| E. | increases conversion of cholesterol to pregnenelone |
| Answer» D. direct positive chronotropic action on heart | |
| 603. |
Normal values for renal function include all of the following EXCEPT: |
| A. | filtration fraction =0.2 |
| B. | 22% of cardiac output |
| C. | GFR = 180 litres/day |
| D. | RPF = 900 litres/day |
| E. | Tm glucose = 450 mg/minute |
| Answer» E. Tm glucose = 450 mg/minute | |
| 604. |
Regarding renal handling of potassium, which is INCORRECT? |
| A. | 10 to 15% of filtered load may be excreted in urine |
| B. | two potassium per sodium are reabsorbed in thick ascending limb |
| C. | excretion decreased in acidosis |
| D. | distal tubular secretion is capable of “adaptation” depending on demand |
| E. | aldosterone increases distal tubular secretion in exchange for sodium |
| Answer» B. two potassium per sodium are reabsorbed in thick ascending limb | |
| 605. |
Normal urinary values include all of the following EXCEPT: |
| A. | albumin ≤ 150mg/day |
| B. | pH = 4.5 to 8.0 |
| C. | volume = 0.5 to 2.4 litres/day |
| D. | specific gravity = 1.010 to 1.035 |
| E. | osmolality = 3 to 1400 millismol/litres |
| Answer» A. albumin ≤ 150mg/day | |
| 606. |
Regarding the kidney: |
| A. | prostaglandins decrease blood flow in renal cortex |
| B. | acetylcholine produces renal vasoconstriction |
| C. | angiotensin II causes constriction of efferent arterioles |
| D. | angiotensin II causes constriction of afferent arterioles |
| E. | glomerular capillary pressure normally is about 100mmHg |
| Answer» C. angiotensin II causes constriction of efferent arterioles | |
| 607. |
Glucose reabsorption is most marked in which segment of the glomerulus? |
| A. | the proximal convoluted tubule |
| B. | the distal convoluted tubule |
| C. | the descending loop of Henle |
| D. | the ascending loop of Henle |
| E. | the collecting system |
| Answer» A. the proximal convoluted tubule | |
| 608. |
Why is NSAIDs use a relative contraindication in patients with chronic renal failure? |
| A. | direct toxic effects on proximal tubule |
| B. | direct toxic effects on collecting ducts |
| C. | indirect toxic effects on loop of Henle |
| D. | inhibition of prostaglandin synthesis which is an important regulator of renal blood flow in arterioles |
| E. | inhibition of prostaglandin synthesis which is an important regulator of renal blood flow in main renal arteries |
| Answer» D. inhibition of prostaglandin synthesis which is an important regulator of renal blood flow in arterioles | |
| 609. |
Characteristics of a substance suitable for measuring GFR do NOT include: |
| A. | freely filtered |
| B. | not toxic |
| C. | no effect on filtration rate |
| D. | not metabolised |
| E. | of low molecular weight |
| Answer» E. of low molecular weight | |
| 610. |
Amino acid reabsorption is most marked in which segment of the glomerulus? |
| A. | the proximal convoluted tubule |
| B. | the distal convoluted tubule |
| C. | the descending loop of Henle |
| D. | the ascending loop of Henle |
| E. | the collecting duct |
| Answer» A. the proximal convoluted tubule | |
| 611. |
Which of the following substances would NOT cause contraction of mesangial cells? |
| A. | angiotensin II |
| B. | dopamine |
| C. | vasopressin |
| D. | histamine |
| E. | platelet activating factor |
| Answer» B. dopamine | |
| 612. |
Chloride may be reabsorbed in the nephron by: |
| A. | passive reabsorption |
| B. | active co-transport with K+ and Na+ |
| C. | OH- /Cl- antiport |
| D. | all of the above |
| E. | none of the above |
| Answer» D. all of the above | |
| 613. |
Which of these factors do NOT affect GFR? |
| A. | renal blood flow |
| B. | ureteral obstruction |
| C. | dehydration |
| D. | a neutral molecule measuring 4 manometer |
| E. | angiotensin II effects on mesangial cells |
| Answer» D. a neutral molecule measuring 4 manometer | |
| 614. |
The collecting duct is the main site of action for which of the following drugs? |
| A. | ethanol |
| B. | demeclocycline |
| C. | thiazide diuretics |
| D. | ethacrynic acid |
| E. | caffeine |
| Answer» B. demeclocycline | |
| 615. |
Which is NOT true of osmotic diuresis? |
| A. | osmotic diuresis is due to the quantity of unreabsorbed solutes |
| B. | decreased water reabsorption in proximal tubules and loops |
| C. | reduced Na+ reabsorption as the limiting concentration gradient is exceeded |
| D. | net loss of Na+ in urine |
| E. | normal water reabsorption in proximal portion of tubules |
| Answer» E. normal water reabsorption in proximal portion of tubules | |
| 616. |
Which of these is NOT a factor affecting acid secretion? |
| A. | intracellular PCO2 |
| B. | carbonic anhydrase level |
| C. | K+ concentration |
| D. | aldosterone concentration |
| E. | none of the above |
| Answer» E. none of the above | |
| 617. |
Regarding the kidney: |
| A. | glucose is reabsorbed mainly in distal tubule |
| B. | normal GFR is 125ml/hour |
| C. | glomeruli filter 180L fluid per day |
| D. | Na+ is actively transported out of think loop of Henle |
| E. | ethanol promotes vasopressin secretion |
| Answer» C. glomeruli filter 180L fluid per day | |
| 618. |
Regarding renal blood flow: |
| A. | blood flow greatest to medulla |
| B. | pressure in renal vein is about 20mmHg |
| C. | angiotensin II constricts efferent arterioles |
| D. | prostaglandins increase blood flow in cortex and medulla |
| E. | renal blood flow = renal plasma flow x 1 haematocrit |
| Answer» C. angiotensin II constricts efferent arterioles | |
| 619. |
Osmolality of tubular fluid: |
| A. | isotonic in proximal tubule |
| B. | isotonic in loop of Henle |
| C. | hypertonic in ascending limb loop of Henle |
| D. | hypotonic in collecting duct |
| E. | hypotonic in proximal tubule |
| Answer» A. isotonic in proximal tubule | |
| 620. |
Regarding the kidney and urine formation: |
| A. | specific gravity is measure of osmolality |
| B. | thin ascending limb relatively impermeable to water |
| C. | thin ascending limb relatively impermeable to Na+ Cl- |
| D. | water diuresis begins about 1 hour after ingestion of a water load |
| E. | high protein diet does not affect concentrating ability of kidney |
| Answer» B. thin ascending limb relatively impermeable to water | |
| 621. |
Regarding tubular reabsorption in kidney: |
| A. | glucose and amino acids passively reabsorbed |
| B. | Cl- mainly actively reabsorbed |
| C. | only passive reabsorption occurs in proximal tubule |
| D. | urea is not passively reabsorbed |
| E. | Na+ actively reabsorbed in most parts of tubule |
| Answer» E. Na+ actively reabsorbed in most parts of tubule | |
| 622. |
In the presence of vasopressin, most filtered water is absorbed in the: |
| A. | proximal tubule |
| B. | loop of Henle |
| C. | distal tubule |
| D. | cortical collecting system |
| E. | medullary collecting system |
| Answer» A. proximal tubule | |
| 623. |
All of the following affect glomerular filtration, EXCEPT: |
| A. | changes in renal flood flow |
| B. | urethral obstruction |
| C. | dehydration |
| D. | oedema outside the renal capsule |
| E. | glomerular capillary permeability |
| Answer» D. oedema outside the renal capsule | |
| 624. |
The thick ascending limb of the loop of Henle: |
| A. | is impermeable to water |
| B. | has maximal permeability to NaCl |
| C. | is relatively permeable to water |
| D. | is impermeable to NaCl |
| E. | is a site where there is no active transport of sodium |
| Answer» A. is impermeable to water | |
| 625. |
In the normal bladder, micturition: |
| A. | is initiated by the pelvic nerves |
| B. | is co-ordinated in the lumbar portion of the spinal cord |
| C. | is initiated at a volume of 600mls |
| D. | is significantly affected by sympathetic nerves |
| E. | is not facilitated at the level of the brain stem |
| Answer» A. is initiated by the pelvic nerves | |
| 626. |
All the following statements regarding the atrial natriuretic peptide (ANP) are true EXCEPT: |
| A. | it causes natriuresis |
| B. | it lowers blood pressure |
| C. | circulating ANP has a short half-life |
| D. | ANP has the greatest affinity for the ANPR-B receptor of the glomerulus |
| E. | it is released when atrial muscle is stretched |
| Answer» D. ANP has the greatest affinity for the ANPR-B receptor of the glomerulus | |
| 627. |
Which part of the renal tubule is Na+ NOT actively transported out of? |
| A. | proximal convoluted tubule |
| B. | thin portions of the loop of Henle |
| C. | thick ascending limb of loop of Henle |
| D. | distal convoluted tubule |
| E. | collecting duct |
| Answer» B. thin portions of the loop of Henle | |
| 628. |
Where is the macula densa located? |
| A. | afferent arteriole |
| B. | efferent arteriole |
| C. | proximal convoluted tubule |
| D. | thick ascending limb of loop of Henle |
| E. | distal convoluted tubule |
| Answer» D. thick ascending limb of loop of Henle | |
| 629. |
What percentage of cardiac output goes to the kidneys at rest? |
| A. | 10% |
| B. | 15% |
| C. | 25% |
| D. | 35% |
| E. | 45% |
| Answer» C. 25% | |
| 630. |
Which factor increases renal blood flow? |
| A. | α1 adrenergic stimulation |
| B. | α2 adrenergic stimulation |
| C. | reduced systemic blood pressure |
| D. | exercise |
| E. | lying down |
| Answer» E. lying down | |
| 631. |
Angiotensin II: |
| A. | constricts afferent arterioles only |
| B. | constricts efferent arterioles only |
| C. | constricts afferent and efferent arterioles |
| D. | dilates afferent arterioles |
| E. | dilates efferent arterioles |
| Answer» C. constricts afferent and efferent arterioles | |
| 632. |
Regarding nephrons permeability: |
| A. | glomerular capillaries are 100 times more permeable than skeletal muscle capillaries |
| B. | anionic substances are more permeable than neutral substances |
| C. | N (?normal) glomerular concentration of albumin is 0.2% of plasma concentration |
| D. | neutral substances are freely filtered with diameters < 8nm |
| E. | 100mg/d of protein is filtered at the glomerulus |
| Answer» C. N (?normal) glomerular concentration of albumin is 0.2% of plasma concentration | |
| 633. |
Where does glucose reabsorption occur? |
| A. | proximal convoluted tubule |
| B. | thin descending limb of loop of Henle |
| C. | thick ascending limb of loop of Henle |
| D. | distal convoluted tubule |
| E. | collecting duct |
| Answer» A. proximal convoluted tubule | |
| 634. |
Vasopressin acts as the: |
| A. | proximal convoluted tubule |
| B. | loop of Henle |
| C. | distal convoluted tubule |
| D. | cortical portion of the collecting duct |
| E. | medullary portion of the collecting duct |
| Answer» D. cortical portion of the collecting duct | |
| 635. |
Regarding the bladder: |
| A. | the external urethral sphincter is made up of smooth muscle cells |
| B. | the internal urethral sphincter does not encircle the urethra |
| C. | pelvic nerves (S2-S4) supply the external sphincter |
| D. | when the bladder is stretched, tension is maintained |
| E. | relaxation of the internal urethral sphincter assists micturition |
| Answer» B. the internal urethral sphincter does not encircle the urethra | |
| 636. |
Which substance relaxes mesangial cells? |
| A. | angiotensin II |
| B. | ADH |
| C. | noradrenaline |
| D. | thromboxane A2 |
| E. | ANP |
| Answer» E. ANP | |
| 637. |
Concerning the kidneys: |
| A. | normal glomerular filtration rate is 250ml/minute |
| B. | normal renal plasma flow is 125ml/minute |
| C. | normal filtration fraction is 0.19 |
| D. | blood flow is normally higher in the medulla than the cortex |
| E. | normal blood volume in the kidneys at any one time is 250ml |
| Answer» C. normal filtration fraction is 0.19 | |
| 638. |
Regarding renal handling of substances: |
| A. | urea is filtered, but not secreted |
| B. | most sodium is resorbed in the loop of Henle |
| C. | creatinine is not filtered, but is resorbed |
| D. | potassium is filtered, but not secreted |
| E. | chloride is secreted and resorbed |
| Answer» A. urea is filtered, but not secreted | |
| 639. |
Which of the following is transported via active transport? |
| A. | chloride |
| B. | hydrogen |
| C. | glucose |
| D. | urea |
| E. | bicarbonate |
| Answer» B. hydrogen | |
| 640. |
Concerning the respiratory exchange ration (R) |
| A. | it falls during exercise |
| B. | it falls in metabolic acidosis |
| C. | the stomach has a positive R during secretion of acid |
| D. | it rises after ingestion of alkali |
| E. | at steady state, it equals the respiratory quotient |
| Answer» E. at steady state, it equals the respiratory quotient | |
| 641. |
Regarding fat metabolism, all are true EXCEPT: |
| A. | brown fat is characterised by a H+ short circuit protein in the mitochondria |
| B. | heparin is a cofactor for lipoprotein lipase |
| C. | ketone bodies accumulate in diabetic ketoacidosis due to reduced removal from the circulation |
| D. | the essential fatty acids are used to produce autocoids |
| E. | there is no major pathway for converting fat to carbohydrate |
| Answer» D. the essential fatty acids are used to produce autocoids | |
| 642. |
Triiodothyronine: |
| A. | is less potent than thyroxine |
| B. | deficiency causes yellow skin due to keratin buildup |
| C. | acts via a tyrosine kinase predominantly |
| D. | causes an increase in Na+ /K+ ATPase activity |
| E. | in both, deficiency but no excess leads to muscle weakness |
| Answer» E. in both, deficiency but no excess leads to muscle weakness | |
| 643. |
Mesangial cells: |
| A. | have a role in the control of GFR |
| B. | are similar to other endothelial cells in the vascular tree |
| C. | are responsible for tubuloglomerular balance |
| D. | contract in response to dopamine |
| E. | relax in response to vasopressin |
| Answer» A. have a role in the control of GFR | |
| 644. |
With regard to water excretion: |
| A. | 280 l is filtered per day |
| B. | it is impossible to excrete more than 23 l/day |
| C. | most regulation is via manipulation of the gradients along the loop of Henle |
| D. | vasopressin acts to insert water channels into the basolateral cell membrane of the collecting ducts |
| E. | water reabsorption in the collecting ducts can alter by a factor of 2.5 dependent on the presence of vasopressin |
| Answer» E. water reabsorption in the collecting ducts can alter by a factor of 2.5 dependent on the presence of vasopressin | |
| 645. |
All of the following are transported across renal tubular cell membranes by secondary active transport, using the energy of the active transport of Na+ , EXCEPT: |
| A. | glucose |
| B. | lactate |
| C. | citrate |
| D. | H+ |
| E. | K+ |
| Answer» E. K+ | |
| 646. |
Regarding the control of GFR: |
| A. | increasing ANP causes contraction of mesangial cells |
| B. | glomerular cap are less permeable than skeletal |
| C. | oedema of kidney causes increase in renal intent po???? |
| D. | efferent arterioles have low reninlard |
| E. | hypoproteinaemia increases GFR |
| Answer» C. oedema of kidney causes increase in renal intent po???? | |
| 647. |
Regarding osmotic diuresis: |
| A. | is secondary to decreased ADH |
| B. | results in hypertonic urine |
| C. | increased water reabsorption in PCT |
| D. | may be seen in patients with diabetes ketoacidosis |
| E. | may be seen in patients with diabetes insipidis |
| Answer» D. may be seen in patients with diabetes ketoacidosis | |
| 648. |
Effective renal plasma flow is best measured using: |
| A. | inulin |
| B. | glucose |
| C. | PAH |
| D. | urea |
| E. | creatinine |
| Answer» C. PAH | |
| 649. |
Substance X is freely filtered by the glomerulus and is not reabsorbed, nor secreted nor metabolized.
|
| A. | 10.5 ml/min |
| B. | 630 ml/min |
| C. | 10.5 mg/min |
| D. | 630 mg/min |
| E. | 60 ml/min |
| Answer» B. 630 ml/min | |
| 650. |
Substance X is freely filtered by the glomerulus and is not reabsorbed, nor secreted nor metabolized.
|
| A. | 10.5 ml/min |
| B. | 630 ml/min |
| C. | 700 ml/min |
| D. | 11.7 ml/min |
| E. | 21.2 ml/min |
| Answer» C. 700 ml/min | |
| 651. |
Substance X is freely filtered by the glomerulus and is not reabsorbed, nor secreted nor metabolized.
|
| A. | 10.5 ml/min |
| B. | 21.2 ml/min |
| C. | 11.7 ml/min |
| D. | 700 ml/min |
| E. | 1273 ml/min |
| Answer» E. 1273 ml/min | |
| 652. |
Substance X is freely filtered by the glomerulus and is not reabsorbed, nor secreted nor metabolized.
|
| A. | 10.5 ml/min |
| B. | 700 ml/min |
| C. | 11.7 ml/min |
| D. | 630 ml/min |
| E. | 778 ml/min |
| Answer» D. 630 ml/min | |
| 653. |
Which is CORRECT? |
| A. | voluntary control of breathing originates in the pons/medulla |
| B. | automatic breathing control descends to the respiratory musculature via the corticospinal tract |
| C. | the reciprocal innervation in automatic breathing is via descending pathways rather than spinal reflexes |
| D. | automatic fibres descend to innervate the external intercostal muscles at each thoracic level to mediate expiration |
| E. | there is no output to the phrenic nerves during expiration |
| Answer» C. the reciprocal innervation in automatic breathing is via descending pathways rather than spinal reflexes | |
| 654. |
Which abolishes automatic respiration? Destruction of: |
| A. | pre-Bottzinger complexes |
| B. | ventral gp respiratory neurons |
| C. | dorsal gp respiratory neurons |
| D. | section at the inferior border of the pons |
| E. | transaction rostral to the pons |
| Answer» A. pre-Bottzinger complexes | |
| 655. |
Which does not stimulate carotid bodies? |
| A. | carbon monoxide poisoning |
| B. | cyanide poisoning |
| C. | hypoxia |
| D. | hypercapnia |
| E. | increased H+ concentration |
| Answer» A. carbon monoxide poisoning | |
| 656. |
All of the following shift the Hb dissociation curve to the right during exercise EXCEPT: |
| A. | increased 2,3 DPG |
| B. | increased pCO2 |
| C. | increased temperature |
| D. | decreased pO2 |
| E. | increased H+ concentration |
| Answer» D. decreased pO2 | |
| 657. |
Hypoxia at high altitudes: |
| A. | is a form of stagnant hypoxia |
| B. | causes symptoms of cyanosis |
| C. | causes severe symptoms in an unacclimatised person at 3,000m |
| D. | can always be reversed with 100% O2 |
| E. | increased H+ concentration |
| Answer» B. causes symptoms of cyanosis | |
| 658. |
Regarding surfactant: |
| A. | infant respiratory distress syndrome can be adequately treated with administration of phospholipids alone |
| B. | cigarette smokers have the same amount of surfactant as non-smokers |
| C. | the phospholipid film is formed by tubular myelin |
| D. | infant respiratory distress syndrome is caused by insufficient surfactant that prevents the alveoli from expanding at first inspiratory effort |
| E. | formation of the phospholipid film is greatly facilitated by the carbohydrate in surfactant |
| Answer» C. the phospholipid film is formed by tubular myelin | |
| 659. |
Regarding the work of breathing during quiet inspiration: |
| A. | elastic work = 80% |
| B. | viscous resistance = 7% |
| C. | airway resistance = 13% |
| D. | when tidal volume versus intrapleural pressure in quiet inspiration are plotted, a straight line results |
| E. | the amount of elastic work required to inflate the whole respiratory system is more than the amount required to inflate the lungs alone |
| Answer» B. viscous resistance = 7% | |
| 660. |
Regarding gas exchange in the lungs: |
| A. | PaO2 in pulmonary capillaries is the same as PaO2 in the aorta |
| B. | diffusing capacity for O2 (DLO2) increases from 25→65ml/min/mmHg during exercise |
| C. | DLO2 is unaffected by beryllium poisoning and sarcoidosis |
| D. | CO2 retention is frequently a problem in patients with alveolar fibrosis |
| E. | decreased secretion of PDGF by alveolar macrophages causes pulmonary fibrosis |
| Answer» B. diffusing capacity for O2 (DLO2) increases from 25→65ml/min/mmHg during exercise | |
| 661. |
Regarding gas exchange in the lungs: |
| A. | N2O is diffusion limited |
| B. | CO is perfusion limited |
| C. | O2 is between N2O and CO but at rest, is perfusion limited |
| D. | diffusing capacity of the lung for a gas is inversely proportionate to the surface area of the alveolocapillary membrane and directly proportional to its thickness |
| E. | at rest, it takes blood 0.25secs to traverse the pulmonary capillaries |
| Answer» C. O2 is between N2O and CO but at rest, is perfusion limited | |
| 662. |
Regarding bronchial tone: |
| A. | substance P causes bronchoconstriction |
| B. | constriction is caused by sympathetic discharge |
| C. | dilation is caused by parasympathetic discharge |
| D. | maximal bronchoconstriction occurs at 4am |
| E. | VIP causes bronchoconstriction |
| Answer» A. substance P causes bronchoconstriction | |
| 663. |
Regarding pulmonary function, which of the following is NOT true? |
| A. | FRC = ERV + RV |
| B. | IRV in men is about 3,3L |
| C. | RV in women is about 1.1L |
| D. | inspiratory capacity in men = 4.8L |
| E. | total lung capacity = 6L in men, 4.2L in women |
| Answer» D. inspiratory capacity in men = 4.8L | |
| 664. |
Regarding the glottis: |
| A. | when laryngeal adductors are paralysed there is inspiratory stridor |
| B. | abductors contract early in inspiration |
| C. | when abductors are paralysed, aspiration pneumonia may result |
| D. | the adductors are supplied by the vagus nerves, the abduction by the hypoglossal nerve |
| E. | in animals with bilateral cervical vagotomy, pulmonary oedema is purely secondary to aspiration |
| Answer» B. abductors contract early in inspiration | |
| 665. |
Regarding oxygen transport: |
| A. | Haemoglobin S has glutamic acid instead of valine in the β chains |
| B. | the O2 saturation of Hb is the percentage of available binding sites that do not have O2 attached |
| C. | the oxygenated form of Hb is the T state |
| D. | cyanosis is more obvious in anaemic patients |
| E. | normal P50 is 27mmHg |
| Answer» E. normal P50 is 27mmHg | |
| 666. |
Regarding the O2 dissociation curve: |
| A. | O2 affinity of Hb is reduced when the curve is shifted to the left |
| B. | decreased 2,3-DPG shifts the curve to the right |
| C. | the Bohr effect is attributed to the action of PCO2 on H+ concentration |
| D. | temperature has no effect on the curve |
| E. | 2,3-DPG levels are reduced at altitude |
| Answer» C. the Bohr effect is attributed to the action of PCO2 on H+ concentration | |
| 667. |
Diffusion is inversely proportional to: |
| A. | the diffusion constant |
| B. | tissue area |
| C. | solubility of the gas |
| D. | square root of the molecular weight |
| E. | the difference in partial pressure |
| Answer» D. square root of the molecular weight | |
| 668. |
In exercise: |
| A. | oxygen consumption is about 6L/min in a moderately fit subject |
| B. | the respiratory exchange ratio rises to 0.8 |
| C. | diffusing capacity increases 3-fold |
| D. | the change in cardiac output is only about a sixth of the increase in ventilation |
| E. | the oxygen dissociation curve moves to the left |
| Answer» C. diffusing capacity increases 3-fold | |
| 669. |
Central respiratory chemoreceptors: |
| A. | are located in the medulla near exit of cranial nerve X, XI |
| B. | respond directly to changes in external PCO2 |
| C. | respond directly to changes in arterial PO2 |
| D. | are located on dorsal surface of medulla |
| E. | respond to pH of CSF |
| Answer» E. respond to pH of CSF | |
| 670. |
Respiratory peripheral chemoreceptors: |
| A. | carotid bodies respond to PO2, PCO2, and pH |
| B. | peripheral chemoreceptor response to arterial PCO2 is more important than central chemoreceptor response |
| C. | aortic bodies are located within the aortic valve ring |
| D. | drop in PO2 < 100mmHg causes increase in firing rate |
| E. | carotid bodies respond to venous PO2 |
| Answer» D. drop in PO2 < 100mmHg causes increase in firing rate | |
| 671. |
Ventilatory response to CO2 is reduced by all EXCEPT: |
| A. | sleep |
| B. | barbiturate overdose |
| C. | increasing age |
| D. | decreasing the work of breathing |
| E. | trained athletes and divers |
| Answer» D. decreasing the work of breathing | |
| 672. |
The surface area of the lungs is: |
| A. | three times the area of skin |
| B. | ten times the area of skin |
| C. | 30 times the area of skin |
| D. | 100 times the area of skin |
| E. | none of the above |
| Answer» C. 30 times the area of skin | |
| 673. |
Site of most / major airway resistance is: |
| A. | trachea |
| B. | main bronchi |
| C. | large bronchi |
| D. | medium sized bronchi |
| E. | bronchioles |
| Answer» D. medium sized bronchi | |
| 674. |
The volume of the anatomical dead space is: |
| A. | 50mL |
| B. | 100mL |
| C. | 150mL |
| D. | 200ml |
| E. | 300ml |
| Answer» C. 150mL | |
| 675. |
Which respiratory volume is INCORRECT? |
| A. | tidal volume is the normal breathing volume |
| B. | vital capacity is the volume from maximal inspiration followed by maximal expiration |
| C. | residual volume is the volume remaining in lungs after maximal expiration |
| D. | functional residual capacity is the volume after normal inspiration |
| E. | total lung capacity is the vital capacity plus residual volume |
| Answer» D. functional residual capacity is the volume after normal inspiration | |
| 676. |
The diffusion constant is proportional to: |
| A. | tissue thickness |
| B. | square root of the molecular weight |
| C. | difference in partial pressures |
| D. | tissue area |
| E. | gas solubility |
| Answer» E. gas solubility | |
| 677. |
Mean pressure (mmHg) in the main pulmonary artery is: |
| A. | 2 |
| B. | 5 |
| C. | 8 |
| D. | 15 |
| E. | 25 |
| Answer» D. 15 | |
| 678. |
Regarding pulmonary blood flow: |
| A. | increased arterial pressure leads to increased pulmonary vascular resistance |
| B. | localised vasoconstriction is directly due to arterial PO2 hypoxia |
| C. | regional differences are due to hydrostatic pressure differences |
| D. | at the apex Pa>Pv>PA |
| E. | pulmonary arteries and veins have transmural pressures equal to alveolar pressure |
| Answer» C. regional differences are due to hydrostatic pressure differences | |
| 679. |
Which is not inactivated by the lungs? |
| A. | serotonin |
| B. | bradykinin |
| C. | leukotrienes |
| D. | prostaglandin E2 |
| E. | vasopressin |
| Answer» E. vasopressin | |
| 680. |
Regarding the alveolar gas equation: |
| A. | the respiratory quotient nears 1.0 with exercise |
| B. | PIO2= barometric pressure – water vapour pressure |
| C. | PACO2 > PaCO2 |
| D. | PAO2 is normally 150mmHg |
| E. | remains valid if there is CO2 present in the inspired gas |
| Answer» A. the respiratory quotient nears 1.0 with exercise | |
| 681. |
The amount of O2 in blood with a PaO2 of 100mmHg is: |
| A. | 0.003ml O2/100ml |
| B. | 0.3ml O2/100ml |
| C. | 3ml O2/100ml |
| D. | 3ml O2/mL |
| E. | 0.3ml O2/L |
| Answer» B. 0.3ml O2/100ml | |
| 682. |
Regarding the O2 dissociation curve: |
| A. | increased PCO2 has a direct effect on the curve, shifting it to the right |
| B. | 2,3-DPG levels rise as altitude |
| C. | the deoxy form of Hb is in the relaxed state |
| D. | CO moves the curve to the left as it has 100 times the affinity of O2 for Hb |
| E. | P50 is at a PO2 of 40mmHg |
| Answer» B. 2,3-DPG levels rise as altitude | |
| 683. |
Which respiratory principle is INCORRECT? |
| A. | Fick’s law states that “the volume of gas per unit time that moves across a sheet of tissue is proportional to the area of the sheet, but inversely proportional to its thickness” |
| B. | the Bohr effect is “the effect of PCO2 on the O2 dissociation curve due to the action of PCO2 on H+ concentration” |
| C. | Henry’s law states that “the amount of gas dissolved is proportional to the partial pressure of that gas” |
| D. | the chloride shift is “the diffusion of HCO3 - in to the cell, with the outward diffusion of Cl- ions to maintain electrical neutrality” |
| E. | the Haldane effect is that deoxygenation of the blood increases its ability to carry CO2 |
| Answer» D. the chloride shift is “the diffusion of HCO3 - in to the cell, with the outward diffusion of Cl- ions to maintain electrical neutrality” | |
| 684. |
Given a PCO2 = 600mmHg and a HCO3- = 28mEq/l there is a: |
| A. | metabolic acidosis |
| B. | metabolic acidosis with renal compensation |
| C. | respiratory acidosis |
| D. | respiratory acidosis with renal compensation |
| E. | respiratory alkalosis |
| Answer» C. respiratory acidosis | |
| 685. |
Regarding the elastic properties of the lung: |
| A. | the lung volume at any given pressure during inflation is larger than during deflation |
| B. | the area under the pressure-volume curve is known as the compliance |
| C. | surface tension is the force acting across an imaginary line in the surface of the liquid |
| D. | pressure generated in an alveolus equals 4T/R |
| E. | surfactant, produced by Type I alveolar cells, reduces surface tension in alveoli |
| Answer» C. surface tension is the force acting across an imaginary line in the surface of the liquid | |
| 686. |
Halving the radius of an airway increases resistance: |
| A. | 2-fold |
| B. | 4-fold |
| C. | 8-fold |
| D. | 16-fold |
| E. | has no effect on resistance |
| Answer» D. 16-fold | |
| 687. |
The major site of resistance in the bronchial tree is the: |
| A. | segmental bronchii |
| B. | medium-sized bronchii |
| C. | small bronchii |
| D. | large bronchioles |
| E. | terminal bronchioles |
| Answer» B. medium-sized bronchii | |
| 688. |
Lung compliance increases with: |
| A. | asthma |
| B. | alveolar oedema |
| C. | pulmonary hypertension |
| D. | atelectasis |
| E. | pulmonary fibrosis |
| Answer» A. asthma | |
| 689. |
The ventilatory response to CO2 is increased by: |
| A. | sleep |
| B. | increasing age |
| C. | trained athlete |
| D. | morphine |
| E. | decreased PO2 |
| Answer» E. decreased PO2 | |
| 690. |
Normally the FEV1 is what percentage of FVC? |
| A. | 50% |
| B. | 60% |
| C. | 70% |
| D. | 80% |
| E. | 90% |
| Answer» D. 80% | |
| 691. |
The calibre of extra-alveolar vessels is primarily determined by: |
| A. | the difference between alveolar pressure and the pressure within them |
| B. | the pressure in the pulmonary artery |
| C. | the lung volume |
| D. | the cardiac output |
| E. | the patient’s fluid status |
| Answer» C. the lung volume | |
| 692. |
Which statement regarding hyperbaric oxygen therapy is INCORRECT? |
| A. | males eliminate carboxy haemoglobin faster than females |
| B. | gas around the body is normal air compressed to the same high pressure |
| C. | it produces marked increases in dissolved oxygen in the blood |
| D. | oxygen is administered at up to 3 atmospheres pressure |
| E. | toxicity includes optic neuritis |
| Answer» A. males eliminate carboxy haemoglobin faster than females | |
| 693. |
All of the following are features of acclimatisation to high altitude EXCEPT: |
| A. | shift to the right of the oxygen dissociation curve |
| B. | increased number of capillaries in peripheral tissues |
| C. | pulmonary vasodilation |
| D. | polycythaemia |
| E. | increased maximum breathing capacity |
| Answer» C. pulmonary vasodilation | |
| 694. |
Which of the following statements is TRUE? |
| A. | pulmonary stretch receptors lie within the airway epithelial cells |
| B. | J receptors, when stimulated, cause slow deep breathing |
| C. | irritant receptors, when stimulated, send impulses up the vagus in unmyelinated fibres |
| D. | irritant receptors are rapidly adapting |
| E. | increased maximum breathing capacity |
| Answer» D. irritant receptors are rapidly adapting | |
| 695. |
Which one of the following statements regarding ventilation is INCORRECT? |
| A. | tidal volume in the average human is 500ml |
| B. | anatomical dead space is the volume of the conducting airway and is about 160ml |
| C. | upper regions of the lung ventilate better than the lower regions |
| D. | you can measure physiological dead space via Bohr’s method to get what is called a Bohr equation which is: VD PACO2-PECO2 VT PACO2 |
| E. | None of the above |
| Answer» C. upper regions of the lung ventilate better than the lower regions | |
| 696. |
The diffusion capacity (DI) of the lung accounts for: |
| A. | P1-P2 |
| B. | area of lung |
| C. | the thickness |
| D. | diffusion constant |
| E. | all of the above |
| Answer» A. P1-P2 | |
| 697. |
Regarding movement to high altitude, which statement is INCORRECT? |
| A. | hyperventilation occurs due to hypoxic stimulation of peripheral chemoreceptors |
| B. | pro-erythroblasts mature into erythrocytes more rapidly than normal |
| C. | renal bicarbonate excretion increases |
| D. | increased numbers of mitochondria appear in the tissues |
| E. | FiO2 decreases with increasing altitude |
| Answer» E. FiO2 decreases with increasing altitude | |
| 698. |
Metabolic functions of the lung include all of the following EXCEPT: |
| A. | conversion of AI to AII by ACE |
| B. | metabolism of AII |
| C. | inactivation of bradykinin |
| D. | removal of serotonin |
| E. | metabolism of arachidonic acid metabolises |
| Answer» B. metabolism of AII | |
| 699. |
Which of the following is INCORRECT? |
| A. | O2 toxicity causes convulsion |
| B. | O2 at 100% in premature infants causes retrolental fibroplasia |
| C. | acclimatisation to high altitudes include a shift to the left of the O2 dissociation curve |
| D. | polycythaemia is a feature of acclimatisation |
| E. | acute mountain sickness is due to hypoxaemia and alkalosis |
| Answer» C. acclimatisation to high altitudes include a shift to the left of the O2 dissociation curve | |
| 700. |
Regarding the neural control of breathing, which statement is INCORRECT? |
| A. | medullary centres are close to but separate from central chemoreceptors |
| B. | during quiet respiration, expiration is a passive event |
| C. | inspiratory medullary neurons supply both phrenic nerves |
| D. | ventral medullary neurons are expiratory and do not discharge spontaneously |
| E. | inspiratory medullary neurons discharge spontaneously at a rate of 12-15 times/minute |
| Answer» D. ventral medullary neurons are expiratory and do not discharge spontaneously | |
Done Reading?