In reply to srbeeram:
The start method is defined in your example - mem_sequence inherites it from uvm_sequence_base. body() is also defined in uvm_sequence_base as a virtual method. So when start() calls body(), it calls mem_sequence::body().
In reply to srbeeram:
The start method is defined in your example - mem_sequence inherites it from uvm_sequence_base. body() is also defined in uvm_sequence_base as a virtual method. So when start() calls body(), it calls mem_sequence::body().