iPhone - How to change the cell height of a tableview when touches it

In my table view i have different size of cells. Each cell has just some text. When a user touches a cell, i want to increase the height of the cell and add some buttons at the bottom of the text. Can some one tell me how can I increase the size of the cell height and add some b开发者_如何学Pythonuttons at the bottom?

Can you animate a height change on a UITableViewCell when selected?