Which of the following changes is most likely to convert a l
     Which of the following changes is most likely to convert a ligand-gated sodium channel into a ligand-gated potassium channel?  A change in the primary amino acid sequence so that the protein is more positively charged  A mutation in the ligand binding site so that k+ can induce the opening of the channel  A mutation that changes the selectivity inter of the channel  A mutation that alters the subcellular location of the channel  None of the above is likely to change the specificity of the sodium channel  Under which of the following conditions do you expect to see treadmilling of the action filament?  The critical concentrations of F-actin are:  (+)-end: 0.12microM (-)-end: 0.6 microM  The cytosolic concentration of G-action-ATP is 0.4 microM, but you have added 0.3 microM of the sequestering protein thymosin to your reaction Thymosin binds to G-actin ATP in a ratio of 1:1  The cytosolic concentration or G-actin-ATP is 0.15 microM and or G-actin ADP is 0.2 micorM.  The cytosolic concentration of G-actin-ATP is 0.7 microM, but your reaction also contains profilin, an enzyme that converts G-actin-ADP into G-actin-ATP  The cytosolic concentration of G-actin-ATP is 0.4 microM. out you have also added the  end capping protein tropomodulin to your reaction  The cytosolic concentration of G-actin-ATP is 0.1 microM  Which of the following statements best describes a feature of mitochondrial DNA?  Mitochondrial DNA is replicated at the same time as nuclear DNA  Mitochondrial DNA is associated with the outer micochondrial membrane  The genome of mitochondria is the same size in all eukaryotic cells.  Mutations in mitochondrial DNA are repaired by an efficient repair machinery  Mitochondrial DNA of human cells only encodes tor a small percentage of proteins mat function in mitochondria   
  
  Solution
1. a change in the primary amino acid sequence so that the protein is more positively charged
2.
3. mutaion in mitochondrial DNA are repaired by an efficient repair machinery
4.

