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Correct choice is (B) micro-electrodes

Best explanation: To study the electrical activities of individual cells, micro electrodes are employed. This type of electrode is SMALL enough with RESPECT to the size of the cells. Typical micro electrodes have tip dimensions ranging from 0.5-5 microns.

The correct answer is (d) hydraulic

To explain I would SAY: HEART pumps blood. It is analogous to WATER. THUS heart can be CONSIDERED as a hydraulic system.

The correct option is (a) paralyzed muscles

For explanation I would SAY: PALSIED is an adjective that means paralyzed. It is used to describe a MUSCLE on which an individual has lost all control (cannot move). Voluntary muscles are the muscles on which the individual has COMPLETE control. Involuntary muscles are the ones on which the individual has no control for example heart WALL muscles.

Correct answer is (d) hydrogen

The explanation: Sodium (Na^+), Potassium (K^+), and Chlorine (Cl^–) are the principal ions INVOLVED with the phenomena of producing cell POTENTIALS. Na+ is present outside the cell membrane and creates a positively CHARGED environment outside the cell membrane. Cl^– is present inside the cell membrane and is RESPONSIBLE for the negative environment inside the cell membrane.

The CORRECT choice is (a) True

The explanation: Two types of micro electrodes are generally used: METALLIC and glass microcapillaries. Metallic electrodes are FORMED from a fine NEEDLE of suitable METAL drawn for a fine tip. Glass electrodes are drawn from Pyrex glass of special grade.

The correct option is (d) RIGHT

To elaborate: 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.

The correct answer is (c) high contact IMPEDANCE

The explanation: Welsh cup electrodes or suction electrodes is a METALLIC cup shaped ELECTRODE which is used for recording ECG from various positions from the chest. It has a high contact impedance as only the rim of the electrode is in contact with the SKIN. It is COMMONLY used to record the unipolar chest leads.

The correct answer is (a) German SILVER

The best EXPLANATION: The most common type of ELECTRODE most routinely used for recording ECG are rectangular or circular SURFACE limb electrodes. The material used in them is German silver, nickel silver or nickel plated STEEL. They are applied to the surface of the body with electrode jelly.

Right ANSWER is (a) 2-200 µV

Explanation: The signal AMPLITUDE of EEG is between 2-200 µV. It is very small and requires SPECIAL TYPE of ELECTRODES namely scalp electrodes. EEGs are difficult to capture because its signal range in very small and motion artifacts are much greater.

The correct CHOICE is (d) hydrogen absorbed on platinum electrode

The EXPLANATION is: All electrode potentials are measured with respect to a REFERENCE electrode, usually that of hydrogen absorbed on platinum BLACK. Thus, CONSIDERING potential of hydrogen absorbed on platinum electrode to be zero, other all have positive of negative potentials.

Correct answer is (b) refactory period

The explanation is: After a cell is stimulated, a finite period of time is required for the cell to return to its pre-stimulus state. This is because the energy associated with the action POTENTIAL is developed from metabolic PROCESS within the cell which takes time for COMPLETION. This time period is CALLED refactory period.

Right CHOICE is (c) micro pipette

To explain I would say: The most commonly used method for making small tip micropipette consists of the circumferential application of heat to a small area of glass tubing which is placed under some initial tension. When the glass softens, the tension is increased very rapidly and the heat is TURNED off. PROPER timing, controlled adjustment of the amount of heat as well as the initial and final tensions and cooling results in the production of microcapillaries with control dimensions.

Correct answer is (c) evoked response

Best 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.

Correct OPTION is (c) multi-element needle electrode

Easiest 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.

Right option is (B) high absorbency buffer layer with isotonic ELECTROLYTE

The explanation is: The MAIN design feature of pregelled disposable electrode that helps in reducing the possibility of artefacts, drift and baseline wandering is the provision of high absorbency buffer layers with isotonic electrolyte. This layer absorbs the effects of movement of the electrode in relationship to the skin and ATTEMPTS to maintain the polarization ASSOCIATED with the half-cell potential constant.

Right option is (a) Willem Einthoven

The explanation is: Willem Einthoven a Dutch physician and PHYSIOLOGIST. He INVENTED the first Electrocardiogram (ECG or ECG) in 1903. He received the Nobel PRIZE for Medicine in 1924 for it.

Correct option is (c) neuron

Best explanation: The basic functional unit of the nervous system is a neuron. A typical neuron consists of a nucleated cell body and has several PROCESSES and branches. The dendrites NORMALLY conduct impulses TOWARDS the cell body and the AXON conducts AWAY from it.

Right answer is (d) can transmit small BIOELECTRIC signals even after getting exposed to large PULSE of energy

To explain: Polarizable electrodes usually employ stainless steel and are used for resting ECG or other situations where there is small LIKELIHOOD that the electrode would be exposed to a large pulse of energy (such as defibrillation discharge) in which case they would retain a residual CHARGE, become polarized, and will no longer transmit the relatively small bioelectric signals, thus become useless.

The correct answer is (c) STEREOTAXIC

The best 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.

The correct answer is (d) teflon

The best 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.

The correct OPTION is (B) False

The explanation: The SURFACE electrodes PICK up the potential difference from the tissue surface when placed over it without damaging the living tissues. They are placed above the skin and cause no HARM to the living tissues. They capture the electrical activities of bunch of tissues together.

The correct answer is (c) ionic

Best explanation: Bioelectric potentials are generated at cellular level and the source of these potentials is ionic in NATURE. The prominent ions are K^+, Na^+, and Cl^–. Electronic potential is seen in commonly USED CELLS for example the Galvanic cell. Mechanical potential is found NOWHERE. ELECTRICAL potential is found in electricity.

Right choice is (b) EMG

Easiest 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.

The correct option is (a) stainless steel

To EXPLAIN: 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.

Correct answer is (a) -70

Easiest explanation: The neurons, like the other cells of the body, are ELECTRICALLY polarized at rest. The interior of the neuron is at a potential of about -70 mV relative to the EXTERIOR. When a neuron is exposed to a stimulus above a certain threshold, a nerve impulse, SEEN as a change in membrane potential, is GENERATED which spreads in the cell RESULTING in the depolarization of the cell.

The correct choice is (d) ELECTROLYSIS

Explanation: Silver-Silver Chloride electrodes are NORMALLY prepared by electrolysis. Two silver discs are suspended in a saline solution. The positive pole of dc supply is CONNECTED to the disc to be chloride and the NEGATIVE pole goes to the other disc.

Right answer is (c) Stainless-steel

Easy explanation: Stainless steel in CONTACT with a saline electrolyte produce a POTENTIAL difference of 10 mV between the electrodes which is much more than the limit (i.e 2.5 mV). Ad-AgCl electrodes give ALMOST noise free characteristics. They are also found to be acceptable from the POINT of view of long TERM drift.

The CORRECT choice is (d) EMG

Easiest explanation: EMG stands of Electromyogram. For recording action potential for individual MOTOR UNITS of muscle fiber, needle ELECTRODES are USED for better diagnostic information. These electrodes fall in the category of deep seated electrodes.

Correct CHOICE is (d) has sustainable current carrying capacity

To explain I would SAY: Metallic electrodes polarize with smaller amplifier input currents. Hence, they tend to develop UNSTABLE electrode offset potential and are THEREFORE not preferred for steady state potential measurement. On the other hand, in CASE of glass micro electrodes have a sustainable current carrying capacity because of the large surface area between the metal and the electrolyte.

Right ANSWER is (a) True

The BEST I can explain: Two types of micro electrodes are generally used: metallic and glass microcapillaries. Metallic electrodes are formed from a FINE needle of suitable metal DRAWN for a fine tip. Glass electrodes are drawn from Pyrex glass of special GRADE.

The CORRECT OPTION is (c) 3

To explain: There are 3 RECOGNIZED CLOUD deployment models. They are – PRIVATE cloud, Public cloud and Hybrid cloud.

Right choice is (a) sino-atrial NODE

To elaborate: Located in the top right ATRIUM NEAR the entry of the vena CAVA, are a group of cells known as the sino-atrial node (SA node) that initiates the heart activity. Because this is also considered as the primary PACEMAKER of the heart. The SA node is 25 to 30 mm in length and 2 to 5 mm in thickness.

The correct answer is (a) DIFFERENCE in half-cell POTENTIALS between two electrodes

To EXPLAIN: The difference in half cell potential that exists between two electrodes is called off-set potential. The differential amplifies USED to measure potentials between two electrodes are generally DESIGNED to cancel the electrode offset potential so that only the signals of interest are recorded.

The correct option is (c) non-polarizing electrodes

For explanation: Non-polarizing electrodes are designed to RAPIDLY dissipate any charge imbalance INDUCED by powerful ELECTRIC discharges such as a DEFIBRILLATION procedure. Rapid depolarization enables the immediate reappearance of bioelectric signals on the monitor after defibrillation. For this reason, non-polarizing electrodes have become the electrodes of choice for monitoring in the intensive CARE units and stress testing procedures.

Correct OPTION is (B) action POTENTIAL

Explanation: An action potential occurs when the potential of the membrane of a GIVEN axonal position increases and decreases rapidly. This depolarization causes depolarization of adjacent positions in a similar WAY. Resting membrane potential or the resting potential is the relative static membrane potential of a quiescent cell.

The CORRECT answer is (C) frontal lobe

Best 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.

Correct answer is (b) RIGHT Atrio-ventricular valve

Best explanation: It’s placed between right atrium and ventricle. It consists of three flaps or CUSPS. It PREVENTS BACKWARD flow of blood from right ventricle to the right atrium.

The correct answer is (b) pneumatic

The explanation is: Respiratory system is a pneumatic system in which an air pump (DIAPHRAGM) alternately creates negative and positive pressures in a SEALED chamber (thoracic CAVITY) and causes air to be sucked into and forced out of a PAIR of elastic bags (lungs). Blood circulatory system is related to HYDRAULIC system.

Right answer is (c) heart sound

The explanation: A phonocardiogram (or PCG) is a RECORD high-constancy recording of sounds and mumble made by the heart with the assistance of the machine called phonocardiography. CONSEQUENTLY, phonocardiography is the chronicle of the considerable NUMBER of sounds made by the heart amid a heart cycle. MOSTLY stethoscope is used phonocardiography.

The correct OPTION is (d) very high

The explanation is: The very high impedance of the metal micro-electrodes is due to the characteristics of the small area metal-electrolyte INTERFACE. Because of very high impedance of micro electrodes, amplifiers with extremely high INPUT impedance are required to avoid LOADING the circuit and to MINIMIZE the effects of small change in interface impedance.

Right choice is (a) left

The best I can explain: 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.