Now, whenever a given organism actually wants to reproduce, one important thing that must take place is the DNA must be replicated within our cells. So in the next several lectures, we're going to discuss the process of DNA replication and how it actually proceeds. And let's begin with the process of unwinding. So recall that any given DNA molecule actually consists of two individual and complementary single stranded DNA molecules. And these two single stranded molecules basically combine via an antiparallel fashion to form our double helix. And the bonds that hold our two individual complementary single stranded DNA molecules are hydrogen bonds between our adjacent nitrogenous basis.