So I’ve been studying DNA replication at A-Level standard Biology, and since I had so much trouble understanding the concept of it all (particularly the differences between the ‘Leading Strand’ and the ‘Lagging Strand’), I thought I’d upload this here in the hopes that it might aid other people studying the same thing!
In short, nucleotides can only be attached to the DNA strand from the 3′ end, so the strand that has a 3′ end can do this easily and fluidly; this strand is the ‘Leading Strand’. The other strand - the one that has a 5′ end - has to be replicated in stages, and so Primers place free nucleotides further along the strand, from which more can be placed in a 5′ to 3′ direction! each little segment of replicated nucleotides is called an ‘Okazaki Fragment’, and these are finally joined by Ligase!
It can be kind of hard to grasp, so this animation should make it easier. It really is something that is better understood once you’ve seen it visually, after all!! ☆
I hope this is at least helpful, and good luck studying people!