$(document).ready(function(){
          $('#portfolio1').hide();
          $('#portfolio2').hide();

          $('#portfolio1-toggle').toggle(

               function()
               { // you can add as much here as you'd like

                    $('#portfolio1').show(400);

                    $('#portfolio1arrow').attr('src','http://www.littlegreenriver.com/wp-content/themes/newriver/images/arrowdown.png');

               }, function() 
               { // same here

                    $('#portfolio1').hide(400);

                    $('#portfolio1arrow').attr('src','http://www.littlegreenriver.com/wp-content/themes/newriver/images/arrowup.png');

               });
               
          $('#portfolio2-toggle').toggle(

               function()
               { // you can add as much here as you'd like

                    $('#portfolio2').show(400);

                    $('#portfolio2arrow').attr('src','http://www.littlegreenriver.com/wp-content/themes/newriver/images/arrowdown.png');

               }, function() 
               { // same here

                    $('#portfolio2').hide(400);

                    $('#portfolio2arrow').attr('src','http://www.littlegreenriver.com/wp-content/themes/newriver/images/arrowup.png');

               });

     });