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#Question id: 2589

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?

#Unit 2. Cellular Organization

  1. A, B and C

  2. A, C and D

  3. A and C only

  4. B and D only

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#Question id: 3295

#Unit 11. Evolution and Behavior

Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian Islands have different elaborate courtship rituals. These rituals involve fighting other males and making stylized movements that attract females. What type of reproductive isolation does this represent?
TLS Online TPP Program

#Question id: 5150

#General Aptitude

If the number 481* 673 is completely divisible by 9, then the smallest whole number in place of * will be : 
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#Question id: 5838

#Unit 8. Inheritance Biology

In the Holliday model describing recombination
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#Question id: 31407

#Unit 7. System Physiology – Animal

Solution A contains 10 mmol/L glucose, and Solution B contains 1 mmol/L glucose. If the glucose concentration in both solutions is doubled, by how much will the flux (flow) of glucose between the two solutions change? 
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#Question id: 11943

#Unit 7. System Physiology – Animal

Which of the following changes tends to increase GFR?