sys.dm_tran_lock shows locked resources and requests for locks on resources, not individual rows, that locked. Each locked resource will hold many rows and, possibly, other objects, locked.
Returns information about currently active lock manager resources. Each row represents a currently active request to the lock manager for a lock that has been granted or is waiting to be granted.
The columns in the result set are divided into two main groups: resource and request. The resource group describes the resource on which the lock request is being made, and the request group describes the lock request.