JQuery - slidedown no desplaze div contiguo

<div id="menu">

	<ul>

		<li <?=strpos($main,'labola')!==false?' class="active"':'';?>><a id="labolaphoto" href="<?=site_url('secciones/labola');?>"><img <?=strpos($main,'labola')!==false?' class="activeimg"':' class="inactiveimg"';?> src="<?=base_url();?>skins/frontend/images/Rlabola.jpg" alt="line"><span <?=strpos($main,'labola')!==false?' class="activespan"':'';?>>LAbola</span></a></li>

		<li <?=strpos($main,'servicios')!==false?' class="active"':'';?>><a id="servicesphoto" href="<?=site_url('secciones/servicios');?>"><img <?=strpos($main,'servicios')!==false?' class="activeimg"':' class="inactiveimg"';?> src="<?=base_url();?>skins/frontend/images/Rservicios.jpg" alt="line"><span <?=strpos($main,'servicios')!==false?' class="activespan"':'';?>>Servicios</span></a></li>

		<li <?=strpos($main,'tarifas')!==false?' class="active"':'';?>><a id="tarifasphoto" href="<?=site_url('secciones/tarifas');?>"><img <?=strpos($main,'tarifas')!==false?' class="activeimg"':' class="inactiveimg"';?> src="<?=base_url();?>skins/frontend/images/Rtarifas.jpg" alt="line"><span <?=strpos($main,'tarifas')!==false?' class="activespan"':'';?>>Tarifas</span></a></li>

		<li <?=strpos($main,'contacto')!==false?' class="active"':'';?>><a id="contactphoto" href="<?=site_url('secciones/contacto');?>"><img <?=strpos($main,'contacto')!==false?' class="activeimg"':' class="inactiveimg"';?> src="<?=base_url();?>skins/frontend/images/Rcontacto.jpg" alt="line"><span <?=strpos($main,'contacto')!==false?' class="activespan"':'';?>>Contacto</span></a></li>

	</ul>

</div>

<div id="table">

	<div id="cell">

		<div id="container">

			<div id="bola">

				<img id="imgbola" src="<?=base_url();?>skins/frontend/images/bola.gif" alt="logo"></br>

			</div>

			<div id="description">

				<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Pellentesque tempor augue eget magna sollicitudin eu egestas risus malesuada. Duis sodales ligula et lacus rutrum a mollis urna tempor. Donec quis nisl quis nulla aliquam fermentum. Morbi cursus orci eu eros commodo sed blandit nisl tempor. Cras sed risus nunc. Aenean suscipit tincidunt nulla, ut pretium erat ultricies id. Aliquam erat volutpat. Aliquam laoreet lorem ut erat volutpat mollis. </p>

			</div>

			<div class="clear"></div>

	</div>

</div>