Chapter 5 · MCQ Read Mode

Biomedical Instrumentation- I

The typical amplitude of a surface electroencephalogram signal is:

Silver/silver chloride is the preferred material for biopotential electrodes because it is:

The most important amplifier characteristic for rejecting 50 Hz mains interference in an ECG is a high:

The driven right-leg circuit in an electrocardiograph is used to:

The current that may cause ventricular fibrillation when applied directly to the heart through an intracardiac catheter is as little as:

At a standard paper speed of 25 mm/s, one small 1 mm square of ECG paper represents:

According to Einthoven's law, the relationship between the bipolar limb leads is:

Alpha rhythm in the electroencephalogram has a frequency of:

EEG electrodes are positioned according to the:

A transducer that requires no external excitation because it generates its own output is:

The gauge factor of a metal foil strain gauge is approximately:

A linear variable differential transformer measures displacement with the advantage of:

Fibrillation potentials recorded at rest with a needle electrode during electromyography indicate:

In automatic oscillometric blood pressure monitors, the parameter measured most reliably is:

Using a blood pressure cuff that is too narrow for the patient's arm will give a reading that is:

In an invasive arterial pressure monitoring system, air bubbles in the tubing will cause:

A fluid-filled arterial pressure monitoring system should ideally have a damping ratio of about:

Impedance pneumography measures respiration by:

The principal limitation of impedance pneumography as an apnoea monitor is that it:

The two wavelengths used in conventional pulse oximetry are:

A pulse oximeter distinguishes arterial from venous and tissue absorption by:

In carbon monoxide poisoning, a pulse oximeter will typically show a reading that is:

The electromagnetic blood flowmeter is based on:

Alternating rather than direct current excitation is used in an electromagnetic flowmeter in order to:

Late decelerations on a cardiotocograph indicate:

A positive exercise stress test is conventionally defined by:

A principal safety advantage of biotelemetry over wired monitoring is that it:

Physiological signals cannot be radiated directly and must modulate a carrier because they:

Frequency modulation is preferred to amplitude modulation in analogue biotelemetry because it:

In frequency division multiplexing of several physiological channels:

According to the Nyquist criterion, an ECG containing frequencies up to 100 Hz must be sampled at at least:

In a multi-patient telemetry ward, individual patients are distinguished by:

Radio frequencies used for implantable telemetry are kept low principally because:

Cochlear implants and rechargeable implanted devices commonly receive power by:

Which telemedicine mode is best suited to reporting radiographs acquired at a remote district hospital?

The greatest practical obstacle to telemedicine in rural Nepal is:

An implantable telemetry device must above all be designed for:

Remote home monitoring of pacemakers and implantable defibrillators is made possible by:

Encryption is particularly important in modern implantable telemetry because:

The Stewart-Hamilton equation calculates cardiac output as the mass of indicator injected divided by the:

In the thermodilution method of measuring cardiac output, the indicator is:

A major practical advantage of thermodilution over dye dilution is that thermodilution:

Thermodilution cardiac output measurement is unreliable in the presence of:

Which wavelength is used to detect indocyanine green in dye dilution because haemoglobin absorption is independent of saturation there?

Pulse contour analysis estimates stroke volume from the arterial waveform using the principle that:

Impedance cardiography works because during systole:

A significant limitation of thoracic impedance cardiography is that it is confounded by:

In Doppler echocardiographic measurement of cardiac output, stroke volume is calculated as:

A patient has an FEV1/FVC ratio of 0.55 with a reduced FEV1. This pattern indicates:

Which lung volume cannot be measured by spirometry?

Helium dilution may underestimate total lung capacity in severe emphysema because:

Body plethysmography measures thoracic gas volume by applying:

According to the Beer-Lambert law, which quantity is directly proportional to the concentration of the absorbing substance?

The principal difference between a colorimeter and a spectrophotometer is that the spectrophotometer:

An enzyme assay in which the rate of change of absorbance is measured over time is called:

Ion-selective electrodes measure ion concentration by a potential that varies with:

The Clark electrode used in a blood gas analyser measures:

An air bubble left in an arterial blood gas syringe will cause:

Immersion oil improves the resolution of a light microscope because it:

Relative centrifugal force depends on the rotor radius and on the:

In an ELISA, incomplete washing between steps will most likely cause:

Which class of biosafety cabinet protects the operator, the sample and the environment, and is the standard in clinical laboratories?

The standard autoclave cycle for sterilisation is:

Definitive confirmation that an autoclave cycle has achieved sterilisation is provided by:

In a Coulter counter, the amplitude of the voltage pulse produced as a cell passes through the aperture is proportional to the cell's:

An audiogram is plotted with hearing level on the vertical axis such that:

The presence of an air-bone gap of more than 15 dB on an audiogram indicates:

Masking of the non-test ear is almost always required during bone conduction testing because:

Interaural attenuation for air conduction with standard supra-aural earphones is approximately:

In the modified Hughson-Westlake technique, after a positive response the intensity is:

A notch at 4 kHz on the pure-tone audiogram is characteristic of:

The speech reception threshold is the level at which the patient can correctly repeat:

A word recognition score that decreases as the presentation level is further increased is called rollover and suggests:

A patient with a purely conductive hearing loss would be expected to have a word recognition score that is:

In Bekesy audiometry, the patient:

Bekesy tracings in which the continuous tone tracing falls far below the interrupted tone tracing at all frequencies (Jerger type III) suggest:

A supra-aural earphone of an audiometer is calibrated using:

Audiometric testing must be carried out in a sound-treated booth because ambient noise: