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TLS Online TPP Program

#Question id: 18786

Flow cytometry is based on light scattering and fluorescence, in which two types of scattering are used Forward light scattering and side scattering, in which forward determines……………while side determines the………….

#Unit 13. Methods in Biology
  1. both the scattering primarily determines the shape only
  2. both the scattering primarily determines the granularity only
  3. Forward scattering detect shape, size while side scattering detects granularity and complexity of the cell
  4. Forward scattering detects granularity and complexity, side scattering and detects detect shape of the cell
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TLS Online TPP Program

#Question id: 2589

#Unit 2. Cellular Organization

Following statements are regarding to the mechanism of thick filament regulation.

A. In vertebrate smooth muscle, phosphorylation of the myosin regulatory light chain (LC) activates contraction.

B. At Ca2+ concentrations of more than 10−6 M, the regulatory light chain is not phosphorylated, and the myosin adopts a folded conformation.

C. When the Ca2+ level rises, Ca2+ binds calmodulin (CaM), which undergoes a conformational change (CaM*). The CaM*-Ca2+ complex binds and activates myosin light chain kinase (MLC kinase), which then phosphorylates the myosin LC. This phosphorylation event unfolds the myosin II, which is now active and can assemble into bipolar filaments to participate in contraction.

D. When the Ca2+ levels drop, the myosin LC is dephosphorylated by myosin light-chain (MLC) phosphatase, which is dependent on Ca2+ for activity, causing muscle relaxation.

Which of the following combination is correct?
TLS Online TPP Program

#Question id: 19793

#Unit 12. Applied Biology

The specificity of cry protein seems to be lost upon reduction of which amino acid residues of the protoxin, but can be restored by reoxidation of these residues?
TLS Online TPP Program

#Question id: 1640

#Unit 4. Cell Communication and Cell Signaling

An immune response against grass pollen often involves:
TLS Online TPP Program

#Question id: 13061

#Unit 13. Methods in Biology

Precision will be reduced, but yield will be increased
Optimisation of a PCR reaction is often a compromise between the competing demands for precision, efficiency and yield. Although the specific effects may vary, generally, increasing the annealing temperature will increase non-specific primer binding and reduce precision. Increasing the length of the elongation phase will reduce the proportion of incomplete newly-synthesised strands and therefore increase yield. In this case, the potential effect on efficiency is unclear. Increasing the elongation phase would increase the reaction time, but the time taken to ramp down to a lower annealing temperature would be reduced.
Arrange in the order of their increasing capacity:
TLS Online TPP Program

#Question id: 1272

#Unit 4. Cell Communication and Cell Signaling

Collagen is exported from the endoplasmic reticulum as