2022 - Multiple Choice Questions
The Hering-Breuer Reflex is initiated by which receptors?
- J-receptors
- Irritant receptors
- Pulmonary stretch receptors
- Pain receptors
Hering-Breuer Reflex prevents over inflation of the lung
What volume of pancreatic secretions are produced each day?
- 100-300mL
- 400-600mL
- 1000-2000mL
- 3000-4000mL
In the kidney, arcuate arteries branch to form what?
- Peritubular capillaries
- Interlobular arteries
- Afferent arterioles
- Interlobal arteries
What is the oxygen saturation of haemoglobin in the foetal umbilical vein?
- 30-40%
- 40-50%
- 60-70%
- 80-90%
In an erect lung, which portion has the lowest PAO2?
- Large airways
- West’s Zone 1 alveoli
- West’s Zone 2 alveoli
- West’s Zone 3 alveoli
Administration of local anaesthetic at which site has the highest rate of systemic absorption?
- Brachial plexus
- Subcutaneous
- Epidural
- Intercostal muscle
This was a repeat question
What is the predominant ion flow during phase 3 of ventricular myocyte action potential?
- Na+ influx
- L-type Ca2+ influx
- K+ efflux
- T-type Ca2+ influx
Which of the following contains the highest oxygen saturation?
- SVC
- Pulmonary artery
- Renal vein
- Coronary sinus
What is the principle or mechanism of how a thermocouple measures temperature?
- Resistance of metal oxide relates to temperature
- 2 dissimilar metals develop a potential difference (voltage difference) according to temperature
- Metal semiconductor which changes its resistance in a predictably non-linear fashion (run-away exponent) with temperature
- When heated, the kinetic energy of the liquid increases and it expands, forcing it up the capillary which correlate with temperature
What is the mechanism of action of fluconazole?
- Inhibits ergosterol synthesis
- Inhibits beta-glucan synthesis
- Inhibits DNA synthesis
- Binds to ergosterol to weaken the cell membrane and cause pores
Which enzyme is involved in the formation of bradykinin?
- Bradykinin converting enzyme
- Kallikrein
- Prostaglandin
- Cytokine
Which of the following is true?
- Chlorhexidine causes oxidative damage
- Iodine is not effective against fungi and spores
- Chlorhexidine 2% with 70% alcohol and povidone-iodine have the same spectrum of activity
- Chlorhexidine has a longer duration of activity than povidone-iodine when applied to the skin
Which of these gases are diffusion limited?
- Carbon dioxide under exercising conditions
- Carbon monoxide under exercising conditions
- Oxygen under resting conditions
- Nitrous oxide
Blockade of the Na+/K+ ATPase channel by digoxin has what effect?
- Increases serum K+ level
- Reduces resting membrane potential
- Prolongs duration of action potential
- Decreases intracellular Ca2+
A subject is given 100% FiO2 and takes a single vital capacity breath followed by a full exhalation. Nitrogen concentration is measured over time and an increase in nitrogen concentration is seen after a plateau. Why does this occur?
- Effect of gas exchange in poorly compliant part of the lung
- Increased dead space
- Less oxygen available in apical alveoli
- Effect of closing capacity exceeding FRC
What is drug bioavailability?
- Percentage of drug excreted by the kidneys
- Portion of free portion in plasma
- Portion of dose administered that reaches hepatic circulation
- Percentage of dose administered that reaches systemic circulation
The equilibrium dissociation constant of a drug relates to which characteristic?
- Receptor affinity
- Peak concentration
- Fat solubility
- Protein binding
In pulse oximetry, what is the isobestic point?
- Upper inflection point at which the oxygen-haemoglobin dissociation curve plateaus
- Point at which oxygen saturation is 50%
- Point at which both deoxy- and oxy-Hb absorb light equally
- Point at which infrared wavelength is maximally absorbed
Which immunoglobulin subtype crosses the placenta?
- IgA
- IgG
- IgM
- IgD