This is because the GP120 protein
of the HIV virus that forms the ‘knob’ is
essential for the infection of CD4 cells
of the immune system by the virus. The glycoprotein is, therefore, a good
target for vaccines especially since the
molecule is highly conserved because most mutations in the region could be highly deleterious to the virus.
<h3><em>Starch is a indicator in the iodometric titration and it turns deep dark blue when iodine is present in a solution. The starch under warming condition forms amylose and amylo pectins which combine with iodine to produce dark blue color.In absence of iodide ion starch indicator is colorless.</em></h3>
