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The correct option is (a) True

Explanation: Coulter counters have a serious drawback LINKED with the mercury manometer ARRANGEMENT. The surface of the mercury gets dirty as a consequence of which the contact bordering the VOLUME becomes UNCERTAIN, which may MAKE the measured values uncertain.

Correct option is (c) 15 x, 40 x

To explain I would say: The system uses a conventional microscope with automatic focus and stage motion. The system is built around a ZEISS microscope with TWO 15 x eyepieces and a 40 x oil immersion objective and with computer controlled focusing. A television monitor displays the DATA and shows the relative position of the cells in each field.

Correct choice is (b) 19 micron

Easy explanation: Ragweed POLLEN (19 micron in diameter) and polystyrene LATEX particles (6–14 micron in diameter) seem to meet these requirements. Of the two, polystyrene latex is preferred for calibration purposes (THOM, 1972). The particles when used seldom plug the ORIFICE. These can be conveniently obtained in the range of 5 million particles per cubic MM.

Right choice is (C) LM337

Explanation: LM337 is a variable negative voltage regulator IC. It is capable of drawing CURRENT up to 1.5A and voltage range from (-1.25V) – (-30V) ideally. LM317 is a variable positive voltage regulator IC. 7905 and 7912 are fixed voltage regulator IC that give OUTPUT voltage as -5V and -12V respectively.

Right choice is (b) dc BRIDGE amplifier

To EXPLAIN I would say: ESSENTIALLY, the amplifier comprises a STABLE dc excitation source, a bridge balance and calibration unit, a high gain differential dc amplifier and a dc output amplifier. DC bridge amplifiers are employed with resistive transducers which require an external source of excitation.They can be used as conventional dc high gain amplifiers and offer OPERATING simplicity and high-frequency response.

The correct OPTION is (c) conformance

Easiest explanation: Hysteresis is changed in output with the same VALUE of input but with a different history of input variation. Conformance indicates the CLOSENESS of a CALIBRATION curve to a SPECIFIED curve for an inherently non linear transducer.The region in which the output does not change with an increase in input is called saturation.

Right choice is (b) Platinum electrode

Easy EXPLANATION: In a coulter counter, a platinum electrode is PLACED INSIDE the orifice tube and a second electrode is submerged into the beaker containing the cell dilution, creating an electrical circuit between the two ELECTRODES.

Right answer is (d) differential amplifiers

Easiest explanation: Most of the amplifiers used for measuring BIOELECTRIC signals are of the differential type. A differential amplifier is one which will REJECT any common mode signal that appears simultaneously at both amplifier INPUT terminals and amplifies only the voltage difference that appears ACROSS its input terminals. AC amplifiers have a limited frequency response and are, therefore, used only for special medical applications such as electrocardiograph machine.

Right CHOICE is (a) THERMOCOUPLE

Easiest explanation: The junction at a higher temperature in thermocouple is termed as measuring junction. This arrangement is called thermocouple.The junction at a LOWER temperature in the thermocouple is called the REFERENCE temperature.

Correct ANSWER is (B) False

For explanation I would say: The junction at a higher TEMPERATURE in thermocouple is termed as measuring junction. The junction at a lower temperature in the thermocouple is called the reference temperature. The cold junction is usually kept at 0*C.

The correct answer is (a) True

Explanation: True, To protect the probe from chemical attack, it must be encapsulated in a biologically inert material having a high electrical and chemical resistance, e.g. silicone rubber. The probes can generally be sterilized by chemical MEANS. Probe calibration is CARRIED out in 0.9% saline during MANUFACTURE and each probe is given a calibration factor that is ENGRAVED on the connector.

The correct answer is (b) Phase sensitive detector

For explanation I would say: A phase sensitive detector is used to recover the SIGNAL, which is an ANALOGUE of the flow RATE being MEASURED. This type of demodulator not only offers maximum signal-to-noise ratio but also helps in the rejection of interfering voltages at frequencies well below the carrier frequency.

The correct answer is (a) settling time

The best explanation: Frequency RESPONSE is the CHANGE of transfer function with frequency, both in magnitude and in phase.Settling time is the time for the sensor to reach a STABLE OUTPUT once it is turned on. The total operating range of the transducer is called the span of the transducer.

Correct option is (b) frequency response

The BEST I can explain: Frequency response is the change of transfer function with frequency, both in magnitude and in phase. It is a dynamic property.The region in which the output does not change with an increase in the input is called saturation. ABILITY of the sensor to REPEAT a measurement when put back in the same ENVIRONMENT is called repeatability.

Correct answer is (C) 632.8 nm

To ELABORATE: The He–Ne LASER operating at 632.8 nm WAVELENGTH is used. The laser output is coupled into the fibre using a converging lens, which results in an increased power density at the skin surface and thus enables the detection of flow in the more deeply seated veins and arteries.

Right answer is (b) Seven

For explanation I would say: The system ELECTRONICALLY examines conventional microscope blood smear slides and EMPLOYS optical pattern recognition techniques to achieve the following:

Counts and differentiates seven IMPORTANT categories of red blood cells (erythrocytes); three based on size, TWO on colour, one on shape and one covering red cells with NUCLEI (nucleated red cells).

Right answer is (a) saturation

To explain: The REGION in which the OUTPUT does not CHANGE with an increase in input is called saturation. The threshold of the transducer is the smallest change in MEASURANT that will result in a measurable change in the transducer output. Offset is the output that will exist when it should be zero.

Right choice is (d) 250 Hz

For explanation I WOULD say: In signal CONDITIONING, ECG signal is amplified, filtered (0.05-100 Hz for diagnostic purposes, 1-40 Hz for MONITORING purposes) and digitized using an 8- or 12-bit analog-to-digital converter with a TYPICAL sampling rate of 250 Hz.

The correct CHOICE is (b) False

Best explanation: It is False. Arrhythmia MONITORS require reliable R wave DETECTORS as a prerequisite for subsequent analysis. The steep, large amplitude variation of the QRS complex is the obvious characteristics to USE and this is the function of the R wave detector.

Right choice is (c) Arrhythmias

Easy explanation: Any disturbance in the HEART’s normal rhythmic contraction is called an arrhythmias or cardiac dysrhythmia. In this arrhythmias heart can’t BEAT in a REGULAR rhythm. In arrhythmia heart-RATE will be HIGHER than normal rate or will be less than the normal rate.

Right ANSWER is (B) Sophisticated alarm system

To explain I would say: An ARRHYTHMIA monitor is basically a sophisticated alarm system. It is not an ECG interpretation system. It constantly scans ECG rhythm patterns and issues alarms to events that may be premonitory or life threatening.

Correct option is (a) True

For explanation I would say: It is True. Digital filters are INSENSITIVE to temperature as compared with analog filters. They are also insensitive to AGEING, VOLTAGE drift and external interference as compared to analog filters. Their response is completely reproducible and predictable, and SOFTWARE simulations can exactly reflect product PERFORMANCE.

Correct option is (B) Modality-Specific

To explain: Interruption or interference with normal physiological and DEVELOPMENTAL PROCESSES or structures is calledPathophysiology. A task that is specific to a single sense or movement pattern is called Modality- Specific. A functional limitation is a restriction or LACK of ability to perform an action in the manner or within the range consistent with the purpose of an organ or organ system.