select option chained from radio button

<!--Script Ajax-->
<script type="text/javascript">

$(function(){

$.ajaxSetup({
type:"POST",
url: "<?php echo base_url('index.php/select/ambil_data') ?>",
cache: false,
});

$("#j_kI").change(function(){

var value=$(this).val();
if(value>0){
$.ajax({
data:{modul:'kamar_ikhwan',id:value},
success: function(respond){
$("#kamar").html(respond);
}
})
}

});
$("#j_kA").change(function(){

var value=$(this).val();
if(value>0){
$.ajax({
data:{modul:'kamar_akhwat',id:'value'},
success: function(respond){
$("#kamar_akhwat").html(respond);
}
})
}

});

})

</script>
<!--END script ajax-->

<!--COntrollel-->
function ambil_data(){

        $modul=$this->input->post('modul');
        $id=$this->input->post('id');
        //kamar
        if($modul=="kamar"){
            echo $this->model_select->kamar_ikhwan();
        }
        elseif($modul=="kamar_akhwat"){
            echo $this->model_select->kamar_akhwat();
        }

    }
<!-- END COntrollel-->

<!--HTML-->
<div class="form-group">
                        <label class="control-label col-md-3 col-sm-3 col-xs-12">Jenis Kelamin
                        </label>
                        <div class="col-md-6 col-sm-6 col-xs-12">
                            Laki-laki: <input type="radio" class="flat" name="j_k" id='j_kI' value="<?php echo $j_k; ?>" checked="" />
                            Perempuan: <input type="radio" class="flat" name="j_k" id="j_kA" value="<?php echo $j_k; ?>" />
                        </div>
            </div>
<div class="form-group">
            <label class="control-label col-md-3 col-sm-3 col-xs-12" for="varchar">Kamar <?php echo form_error('kamar') ?></label>
                <div class="col-md-6 col-sm-6 col-xs-12">
                    <select class='form-control' id='kamar' name="kamar">
                        <option value='0'>--pilih--</option>

                    </select>
                </div>
        </div>
<!--END HTML-->

<!--Model-->
function kamar_akhwat(){
        $kamar="<option value='0'>--pilih--</pilih>";

        $this->db->order_by('kamar','ASC');
        $jur= $this->db->get('kamar_akhwat');

        foreach ($jur->result_array() as $data ){
            $jur1.= "<option value='$data[id]'>$data[kamar]</option>";
        }
    return $jur1;
    }
    function kamar_ikhwan(){
        $kamar="<option value='0'>--pilih--</pilih>";

        $this->db->order_by('kamar','ASC');
        $jur= $this->db->where('kamar');

        foreach ($jur->result_array() as $data ){
            $jur1.= "<option value='$data[id]'>$data[kamar]</option>";
        }
    return $jur1;
    }
<!--END model-->