512 byte boot.img

[k2011gen]

>From the grub2 manual

boot.img
    On PC BIOS systems, this image is the first part of GRUB to start. It is 
written to a master boot record (MBR) or to the boot sector of a partition. 
Because a PC boot sector is 512 bytes, the size of this image is exactly 512 
bytes. 


I always thought that the 512 byte MBR also includes the Partition-Table. So 
with the boot.img being 512 bytes and being written to the disk root sector 
what happens to the PT?
  



Another Q:

Just to confirm that the image that grub-mkimage makes is the core.img?



TIA