The R group of an amino acid determines

Antibodies function in

2. An example of a trans acting element in eukaryotic transcription will be:  

5. Which one of the following best describes the cap modification of eukaryotic mRNA?

11. Which among the following sequence is present at the 3’ terminal of all tRNA?

Which type of overpotential results directly from the resistance of the electrolyte solution between two electrodes?   Concentration overpotential Activation overpotential Ohmic overpotential Polarization overpotential

An instructor is demonstrating a Wheatstone bridge circuit to a biomedical instrumentation class. The bridge has four arms (with resistors R1 to R4) and is powered by a DC supply. When all four resistors are equal, the voltmeter reads zero. The instructor then replaces R1 with a strain gage bonded to a test beam and presses on the beam, causing the voltmeter to give a reading.  How does replacing one fixed resistor with a strain gage in a Wheatstone bridge allow the circuit to detect small resistance changes?   The bridge amplifies the supply voltage in proportion to the gauge resistance, giving a larger absolute output.  The bridge stores charge until enough resistance change accumulates, then releases it as a pulse proportional to total displacement.  Starting from a perfectly balanced (zero-output) condition, any tiny resistance change in the gage arm immediately creates an imbalance voltage Vab that is directly related to ΔR, allowing small displacements to be detected.  The other three fixed resistors act as reference standards that calibrate the gauge reading automatically on each measurement.

Multiple Choice Questions. Write the letter of the single best answer for each number on your paper. Fifteen items, each one is worth 3 points. (45 points total)

Which of the following is NOT one of the five components of the input signal to a biopotential measurement system?   The desired biopotential Undesired biopotentials Amplified output signal Power line interference (60 Hz and harmonics)

What if the high-pass filter in an EMG measuring device failed and stopped functioning, essentially becoming a wire? If this happens during an EMG recording session on the patient’s bicep and the patient frequently moves his arm, disturbing the electrode-skin contact, what would most likely appear in the output signal?   Complete loss of the EMG signal Large, slow-varying baseline wander and DC offset that could saturate the subsequent amplifier stages Increased 60 Hz power line interference Loss of the high-frequency components of the EMG signal