#Question id: 11720
#Unit 6. System Physiology – Plant
The embryo, which will grow into the new seedling, has a specialized absorptive organ that is___
#Question id: 3736
#Unit 3. Fundamental Processes
What is the DNA sequence (5ʹ → 3ʹ) determined in this gel sequenced by Sanger's methods? Assume the samples were applied near the top of the gel.
#Question id: 10739
#Unit 10. Ecological Principles
A rat that is "maze-dull"
#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?
#Question id: 702
#Unit 1. Molecules and their Interaction Relevant to Biology
Proteins often have regions that show specific, coherent patterns of folding or function. These regions are called: