<Tr> <Td_colspan="7"> Meredith works to save the life of a paramedic, after his colleague died . Meredith asks Derek not to see other people after taking inspiration from some advice Webber gave a patient . Derek has to rely on Rose after the camera monitor breaks during the middle of a surgery, which leads to the pair sharing a kiss . Alex is suspended for a week for sneaking Rebecca in to observe a surgery . Izzie realizes that she is not cut out for cardio surgery . Tensions between Bailey and Tucker reach a breaking point . Cristina takes pity on Lexie, after her actions lead to the death of a patient . </Td> </Tr> <Tr> <Th> 72 </Th> <Td> 11 </Td> <Td> "Lay Your Hands on Me" </Td> <Td> John Terlesky </Td> <Td> Allan Heinberg </Td> <Td> January 10, 2008 (2008 - 01 - 10) </Td> <Td> 17.68 </Td> </Tr> <Tr> <Td_colspan="7"> When Bailey's son, Tuck, is at Seattle Grace following a bookshelf falling on him, she starts to feel that she might be a bad mother . Tucker and Bailey separate . The return of George's mother brings Callie and George together once more, and his relationship with Izzie has failed . Izzie and Cristina continue their rivalry, and Izzie later admits to Alex that it is based on jealousy . A healer with "powers" at Seattle Grace makes the doctors question science and faith . Meredith discovers Rose and Derek have kissed, which leads to them breaking up . Lexie suffers an allergic reaction after Meredith makes her breakfast . </Td> </Tr> <Tr> <Th> 73 </Th> <Td> 12 </Td> <Td> "Where the Wild Things Are" </Td> <Td> Rob Corn </Td> <Td> Zoanne Clack </Td> <Td> April 24, 2008 (2008 - 04 - 24) </Td> <Td> 16.37 </Td> </Tr>

Why do meredith and derek break up in season 4