function fillCategory(){ 
 // this function is used to fill the category list on load
addOption(document.drop_list.Category, "Apoptosis", "Apoptosis", "");
addOption(document.drop_list.Category, "Genomics", "Genomics", "");
addOption(document.drop_list.Category, "Proteomics", "Proteomics", "");
}

function SelectSubCat(){
// ON selection of category this function will work

removeAllOptions(document.drop_list.SubCat);
addOption(document.drop_list.SubCat, "", "Then Select Product", "");

if(document.drop_list.Category.value == 'Apoptosis'){
addOption(document.drop_list.SubCat,"AVK050", "AVK050");
addOption(document.drop_list.SubCat,"AVK250", "AVK250");
addOption(document.drop_list.SubCat,"AVF250", "AVF250");
addOption(document.drop_list.SubCat,"AVF500", "AVF500");
addOption(document.drop_list.SubCat,"AV100", "AV100");
}
if(document.drop_list.Category.value == 'Genomics'){
addOption(document.drop_list.SubCat,"DLB01", "DLB01");
addOption(document.drop_list.SubCat,"DGM01", "DGM01");
addOption(document.drop_list.SubCat,"DGM02", "DGM02");
addOption(document.drop_list.SubCat,"PVK01", "PVK01");
addOption(document.drop_list.SubCat,"PV01", "PV01");
addOption(document.drop_list.SubCat,"SDMI-100", "SDMI-100");
addOption(document.drop_list.SubCat,"TAQ01", "TAQ01");
addOption(document.drop_list.SubCat,"TAQ02", "TAQ02");
}
if(document.drop_list.Category.value == 'Proteomics'){
addOption(document.drop_list.SubCat,"PAK150 ", "PAK150 ");
addOption(document.drop_list.SubCat,"PAK500 ", "PAK500 ");
addOption(document.drop_list.SubCat,"PGFS500", "PGFS500");
addOption(document.drop_list.SubCat,"PGFS1000", "PGFS1000");
}

}
////////////////// 

function removeAllOptions(selectbox)
{
	var i;
	for(i=selectbox.options.length-1;i>=0;i--)
	{
		//selectbox.options.remove(i);
		selectbox.remove(i);
	}
}


function addOption(selectbox, value, text )
{
	var optn = document.createElement("OPTION");
	optn.text = text;
	optn.value = value;

	selectbox.options.add(optn);
}