McqMate
These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: Biomedical Engineering .
Chapters
| 1. |
The frequency range of ECG is |
| A. | 0.05-150 HZ |
| B. | 500-1500 Hz |
| C. | 5-500 kHz |
| D. | 0.5-150 MHz |
| Answer» A. 0.05-150 HZ | |
| Explanation: The diagnostically useful frequency range is usually accepted as 0.05 to 150 Hz. Although the electric field generated by the heart can be best characterized by vector quantities, it is generally convenient to directly measure only scalar quantities, i.e. a voltage difference of mV order between the given points of the body. | |
| 2. |
Which of the following amplifier circulatory is employed to reduce the hum noise generated by the power supply in the ECG circuit? |
| A. | band pass filters |
| B. | high pass filters |
| C. | notch filters |
| D. | low pass filters |
| Answer» C. notch filters | |
| Explanation: A notch filter is employed to suppress the hum noise generated by the power supply in the ECG circuit. CMRR of the order of 100–120 dB with 5 kW unbalance in the leads is a desirable feature of ECG machines. The instability of the baseline, originating from the changes of the contact impedance, demands the application of the automatic baseline stabilizing circuit. | |
| 3. |
The branch of medicine that deals with the provision and use of artificial devices such as splints and braces is |
| A. | prosthetics |
| B. | orthotics |
| C. | laproscopic |
| D. | augmentative communication |
| Answer» C. laproscopic | |
| Explanation: The branch of medicine that deals with the provision and use of artificial devices such as splints and braces are orthotics. A modality-specific appliance that aids the performance of a function or movement by augmenting or assisting the residual capabilities of that function or movement. An orthopaedic brace is an orthosis. | |
| 4. |
The sensitivity of an electrocardiograph is typically set at 10 mm/mV. |
| A. | True |
| B. | False |
| Answer» A. True | |
| Explanation: It is true. The sensitivity of an electrocardiograph is typically set at 10 mm/mV. For routine work, the paper recording speed is 25 mm/s. Amplitude measurements are made vertically in millivolts. Time measurements and heart rate measurements are made horizontally on the electrocardiogram. | |
| 5. |
The volume of blood within the dialyzer is known as |
| A. | secondary volume |
| B. | quarterly volume |
| C. | priming volume |
| D. | residual volume |
| Answer» C. priming volume | |
| Explanation: The volume of blood within the dialyzer is known as priming volume. It is desirable that this should be minimal. Priming volume of present day dialyzers ranges from 75 to 200 ml, depending on the membrane area geometry and operating conditions. | |
| 6. |
The ideal membrane should possess to water. |
| A. | low permeability to water |
| B. | high permeability to water |
| C. | medium permeability to water |
| D. | high permeability to waste |
| Answer» B. high permeability to water | |
| Explanation: The ideal membrane should possess high permeability to water, organic metabolites and ions, and the capability of retaining plasma proteins. The membrane should be of sufficient wet strength to resist tearing or bursting and non-toxic to blood and all body cells. | |
| 7. |
To achieve optimum performance and to enable the relationship of change in resistance with the volume of the cell to hold good, it is recommended that the ratio of the aperture length to the diameter of the aperture should be |
| A. | 75:1 |
| B. | 0.75:100 |
| C. | 0.75:1 |
| D. | 0.5:10 |
| Answer» C. 0.75:1 | |
| Explanation: To achieve optimum performance and to enable the relationship of change in resistance with volume of the cell to hold good, it is recommended that the ratio of the aperture length to the diameter of the aperture should be 0.75:1, i.e. for an orifice of 100 m diameter the length should be 75 m. The instrument based on the Coulter principle works most satisfactorily when the average diameter of the particles ranges between 2 to 40% of the diameter of the measuring hole. | |
| 8. |
The blood is a poor conductor of electricity. |
| A. | True |
| B. | False |
| Answer» A. True | |
| Explanation: It is true. Blood is a poor conductor of electricity. This principle is used in Coulter counters to count the number of RBCs in the blood. | |
| 9. |
In floating electrodes metal electrode does not make direct contact with the skin. |
| A. | True |
| B. | False |
| Answer» A. True | |
| Explanation: In a floating electrode, the metal electrode does not make direct contact with the skin. The electrode consists of a light weighted metalled screen or plate held away from the subject by a flat washer which is connected to the skin. Floating electrodes can be recharged, i.e. the jelly in the electrodes can be replenished if desired. | |
| 10. |
The number of leads necessary for an ECG is |
| A. | 3 |
| B. | 6 |
| C. | 12 |
| D. | 24 |
| Answer» A. 3 | |
| Explanation: To have an ECG, the number of leads necessarily needed is 3. These three leads are placed on the four limbs in various combinations to derive the ECG. A 12 lead ECG is used for a greater in-depth analysis. It is used while taking a treadmill test. | |
| 11. |
Which of the four limbs acts like a ground and thus is not a part of the ECG test? |
| A. | Right Arm |
| B. | Left Arm |
| C. | Right Leg |
| D. | Left Leg |
| Answer» C. Right Leg | |
| Explanation: In the various combinations to take ECG, the right leg is considered to be grounded and so no leads are placed on it to take an ECG. It may sometimes have a lead line for grounding but otherwise, that leg does not take part in ECG testing. | |
| 12. |
What result do the various combinations of limb leads give? |
| A. | Einthoven’s Triangle |
| B. | Beethoven’s Triangle |
| C. | Bermuda’s Triangle |
| D. | Electrical Triangle |
| Answer» A. Einthoven’s Triangle | |
| Explanation: The leads are arranged in 3 combinations making one limb positive, one negative and the third as a neutral. There is a vector arrow drawn from the negative side to the positive side. The three arrangements thus result in a triangle which is called the Einthoven’s triangle. | |
| 13. |
The most common placement of the leads from the Einthoven’s triangle is |
| A. | Positive Left Arm and Negative Right Arm |
| B. | Positive Left Leg and Negative Right Arm |
| C. | Positive Left Leg and Negative Left Arm |
| D. | Positive Right Arm and Negative Left Leg |
| Answer» B. Positive Left Leg and Negative Right Arm | |
| Explanation: The Einthoven’s triangle forms a cyclic vector in form of direction. The most important readings are from the 2nd placement of leads in which the Left Leg is positive, the Right Arm is Negative and the Left Arm is neutral. The vector direction is from the right arm to the left leg. | |
| 14. |
A typical ECG wave is |
| A. | Periodic |
| B. | A-periodic |
| C. | Quasi – Periodic |
| D. | Non – Periodic |
| Answer» C. Quasi – Periodic | |
| Explanation: ECG wave comprises PQRSTU segments. In this, P, R, T, U are all waves that go above the baseline and Q, S are waves that go below. However, P wave and R wave are not periodic. Periodicity is checked between the successive R waves. Quasi periodic waves are those which are periodic in a certain interval. Since the ECG signal is periodic in R to R interval or P to P interval, its a Quasi periodic wave. | |
| 15. |
The amplitudes of the segments of the wave are |
| A. | P = 0.25 mV, Q = 0.4mV, R = 1.60mV, T = 0.1 – 0.5 mV |
| B. | P = 2.0 mV, Q = 0.1mV, R = 1.60mV, T = 0.1 – 0.5 mV |
| C. | P = 25.0mV, Q = 4.0mV, R = 16.0 mV, T = 10 – 50 mV |
| D. | P = 0.25 mV, Q = 0.60mV, R = 1.60mV, T = 0.1 – 1.0 mV |
| Answer» A. P = 0.25 mV, Q = 0.4mV, R = 1.60mV, T = 0.1 – 0.5 mV | |
| Explanation: The waves of ECG are a result of electrical impulses and so they have an amplitude. The various waves are a result of the stepwise contractions of the heart. P wave is the depolarization of the atria, QRS complex is formed due to depolarization of the ventricles and then T wave represents the re-polarization of the ventricles. | |
| 16. |
Bradycardia ECG will show what kind of wave? |
| A. | The impulses have increased |
| B. | The impulses have decreased |
| C. | Pronounced P waves |
| D. | Pronounced T waves |
| Answer» B. The impulses have decreased | |
| Explanation: Bradycardia is a symptom where the heartbeat is below the normal range. The heart pumps blood slowly so the impulses are not so pronounced. In tachycardia, the impulses increase. The waves are shorter and sharper. | |
| 17. |
Which of these conditions are natural conditions for tachycardia? |
| A. | Running |
| B. | Grief |
| C. | Shock |
| D. | Sleep |
| Answer» A. Running | |
| Explanation: When a person has run for a stretch, their heart rate goes up. This is a normal tachycardia condition and eventually, the heart rate will go back to normal. When the body gets used to running due to training, the heart also adjusts and is able to pump blood better without | |
| 18. |
Electrodes to measure EEG are placed on |
| A. | forehead |
| B. | scalp |
| C. | cheek |
| D. | ears |
| Answer» B. scalp | |
| Explanation: Electrode to measure EEG are placed on the scalp. The position of each electrode is specified using the International 10/20 system. Each electrode site is labeled with a letter and a number. | |
| 19. |
According to the international 10/20 system to measure EEG, even number denotes which side of the brain? |
| A. | left |
| B. | top |
| C. | bottom |
| D. | right |
| Answer» D. right | |
| Explanation: The position of each electrode is specified using the International 10/20 system. Each electrode site is labeled with a letter and a number. Even number denotes the right side of the head. | |
| 20. |
Letter F in the EEG electrode placement system denotes? |
| A. | front |
| B. | face |
| C. | frontal lobe |
| D. | fast |
| Answer» C. frontal lobe | |
| Explanation: F denotes frontal lobe of the head. The position of each electrode is specified using the International 10/20 system. Each electrode site is labeled with a letter and a number. | |
| 21. |
Normal EEG frequency range is |
| A. | 50-500Hz |
| B. | 0.5-50HZ |
| C. | 0.05-5Hz |
| D. | 1-200Hz |
| Answer» B. 0.5-50HZ | |
| Explanation: The frequency varies greatly with different behavioral states. The normal EEG frequency content ranges from 0.5 to 50Hz. The nature of the wave varies over the different parts of the scalp. | |
| 22. |
The letter T in the EEG electrode placement system denotes? |
| A. | temporal lope |
| B. | temper lobe |
| C. | trace |
| D. | timpanic |
| Answer» A. temporal lope | |
| Explanation: T denotes temporal lobe of the head. The position of each electrode is specified using the International 10/20 system. Each electrode site is labeled with a letter and a number. | |
| 23. |
According to the international 10/20 system to measure EEG, odd number denotes which side of the brain? |
| A. | left |
| B. | right |
| C. | top |
| D. | front |
| Answer» A. left | |
| Explanation: The position of each electrode is specified using the International 10/20 system. Each electrode site is labeled with a letter and a number. Odd number denotes the left side of the head. | |
| 24. |
The delta wave in EEG ranges from |
| A. | 0.5-4Hz |
| B. | 4-8Hz |
| C. | 8-13Hz |
| D. | 13-22Hz |
| Answer» A. 0.5-4Hz | |
| Explanation: The delta wave in EEG ranges from 0.5-4Hz. The theta wave in EEG ranges from 4-8Hz. The alpha wave in EEG ranges from 8-13Hz and beta from 13-22Hz. | |
| 25. |
Disturbance in the EEG pattern resulting from the external stimuli is called |
| A. | provoked response |
| B. | ckoored response |
| C. | evoked response |
| D. | impulse response |
| Answer» C. evoked response | |
| Explanation: Disturbance in the EEG pattern resulting from the external stimuli is called evoked response. The stimuli could be a flash light or a click of sound. The stimuli can be repeated and the EEG waveform can be observed to find the activities occurring because of the stimuli. | |
| 26. |
The peak to peak amplitude of the waves that can be picked from the scalp is |
| A. | 100mV |
| B. | 100V |
| C. | 100uV |
| D. | 10mV |
| Answer» C. 100uV | |
| Explanation: The EEG signal can be picked up with electrodes either from the scalp or directly from the cerebral cortex. The peak to peak amplitude of the waves that can be picked up from the scalp is normally 100uV. The frequency varies greatly with different behavioral states. | |
| 27. |
Which rhythm is the principal component of the EEG that indicates the alertness of the brain? |
| A. | theta rhythm |
| B. | gamma rhythm |
| C. | beta rhythm |
| D. | alpha rhythm |
| Answer» D. alpha rhythm | |
| Explanation: The alpha rhythm is the principal component of the EEG and is an indicator of the state of alertness of the brain. It serves as an indicator of the depth of anesthesia in the operating room. The frequency of the EEG seems to be affected by the mental activity of a person. Topic 2.4 EMG– unipolar and bipolar mode. | |
| 28. |
Which of the following is a preferred electrode for measuring EMG? |
| A. | surface electrodes |
| B. | needle electrodes |
| C. | pregelled electrodes |
| D. | scalp electrodes |
| Answer» B. needle electrodes | |
| Explanation: Electrodes for EMG work are usually of the needle type. Needle electrodes are used in clinical EMG, neurography and other electrophysiological measurements of the muscle tissues underneath the skin. Surface electrodes are preferred to measure ECG. Scalp electrodes for EEG. | |
| 29. |
Generally what is the material of needle electrodes? |
| A. | stainless steel |
| B. | copper |
| C. | lead |
| D. | iron |
| Answer» A. stainless steel | |
| Explanation: The material of the needle electrode is generally stainless steel. In spite of the face that stainless steel is unfavorable electrode material from the point of view of noise, it is preferred in EMG work. It is due to its mechanical solidity and low price. | |
| 30. |
Monopolar needle electrodes are having coatings of which material over the stainless steel wires which are bare only at the tips? |
| A. | carbon |
| B. | calcium |
| C. | sodium |
| D. | teflon |
| Answer» D. teflon | |
| Explanation: The monopolar needle electrode consists of a teflon coated stainless steel wire. The wire is bare only at the tip. It is found that after the needle has been used a number of times, the teflon coating will recede, increasing the tip area. The needle should be discarded when this happens. | |
| 31. |
Which electrode can be used to pick up signals from individual fibers of muscle tissues? |
| A. | biopolar needle electrode |
| B. | concentric core needle electrode |
| C. | multi-element needle electrode |
| D. | monopolar needle electrode |
| Answer» C. multi-element needle electrode | |
| Explanation: Multi-element needle electrodes are used to pick up the signals from individual fibers of muscle tissue. Special needles are available using 25-micron diameter electrode surfaces. They have up to 14 pickup surfaces down the side of one needle. | |
| 32. |
instrument is used to hold patients head and guide the placement of electrodes. |
| A. | Monotaxic |
| B. | Stereotonic |
| C. | Stereotaxic |
| D. | Monotonic |
| Answer» C. Stereotaxic | |
| Explanation: For measurement of potential from specific part of the brain, longer needles are inserted inside the head. The needles are precisely located by means of a map or atlas of the brain. A special instrument called stereotaxic instrument is used to hold the subject’s head and guide the placement of the electrodes. | |
| 33. |
Number of cloud deployment models that are recognized are |
| A. | 2 |
| B. | 5 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| Explanation: There are 3 recognized cloud deployment models. They are – Private cloud, Public cloud and Hybrid cloud. | |
| 34. |
The ground electrode is usually positioned over which body structures? |
| A. | bony |
| B. | hairy |
| C. | fleshy |
| D. | sweaty |
| Answer» A. bony | |
| Explanation: The ground electrode is usually positioned over bony structures rather than over large muscle masses, in the vicinity of the recording and stimulating electrodes, and where possible, equidistant from them. Hairy areas don’t transmit proper signals. It increases impedance of the skin. | |
| 35. |
When intramuscular EMG is required to look into the electrical activities of deeper or overlaid muscles, electrodes are used. |
| A. | plate shape electrodes |
| B. | surface electrodes |
| C. | thin thread electrodes |
| D. | fine wire electrodes |
| Answer» D. fine wire electrodes | |
| Explanation: When intramuscular EMG is required to look into the electrical activities of deeper or overlaid muscles, thin and flexible fine wire electrodes are used. These electrodes are inserted into the muscle site of interest. The needle or steel cannula is removed, and the electrode wires are connected to the steel spring adapters to minimize movement artefacts. | |
| 36. |
The contraction of the skeletal muscles results in the generation of action potential in the individual muscle fibers. Record of this action potential is called |
| A. | ECG |
| B. | EMG |
| C. | EEG |
| D. | EKG |
| Answer» B. EMG | |
| Explanation: The contraction of the skeletal muscles results in the generation of action potential in the individual muscle fibers, a record of such action potential is known as electromyogram (EMG). The activity is similar to that observed in the cardiac muscles (ECG or EKG), but in the skeletal muscles, repolarization takes place much more rapidly. The action potential lasts for only few milliseconds. | |
| 37. |
In voluntary contraction of the skeletal muscles, the muscle potential ranges from |
| A. | 50 uV – 5 mV |
| B. | 50 mV – 5 V |
| C. | 0.05 uV – 2 mV |
| D. | 50 mV – 500 mV |
| Answer» A. 50 uV – 5 mV | |
| Explanation: In voluntary contraction of the skeletal muscles, the muscle potential ranges from 50 uV – 5 mV and duration from 2 to 15 ms. The values vary with the anatomic position of the muscle and the size and location of the electrode. In a relaxed muscle there are no action potentials. | |
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