How do I get the first cell of a selected row in the checkbox?

How do I get the first cell of a selected row in the checkbox?

<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.1/jquery.min.js">
</script>
<script>
$(document).ready(function(){

  $("button").click(function(){
    

     $("tr").each(function(){      

$("input[type=checkbox]:checked").parents(" tr td:first-child").css('background-color','red');

    });
  });
  $("th").css("background-color","#cccccc");
});
</script>
</head>
<body>

<h1>Welcome to My Web Page</h1>

<table border="1">
<tr>
  <th>Company</th>
  <th>Country</th>
</tr>
<tr>
<td>Alfreds Futterkiste</td>
<td>Germany</td>
<td><input type="checkbox" /></td>
</tr>
<tr>
<td>Berglunds snabbköp</td>
<td>Sweden</td>
<td><input type="checkbox" /></td>
</tr>
<tr>
<td>Centro comercial Moctezuma</td>
<td>Mexico</td>
<td><input type="checkbox" /></td>
</tr>
<tr>
<td>Ernst Handel</td>
<td>Austria</td>
<td><input type="checkbox"  /></td>
</tr>
<tr>
<td>Island Trading</td>
<td>UK</td>
<td><input type="checkbox" /></td>
</tr>
</table>
<button>Selecionar 1 celula de cada linha</button>
</body>
</html>