Bridge to the New World How and when humans first came to the Americas has long been a topic of intense debate. Theories to explain the colonization of the New Worldâthe last great habitable landmass to be occupied by humansâfocus on the Bering land bridge, or Beringia, which emerged between Siberia and Alaska during the last ice age.
DNA ligase I: ligates the nascent DNA of the lagging strand after the Ribonuclease H has removed the RNA primer from the Okazaki fragments. DNA ligase III: complexes with DNA repair protein XRCC1 to aid in sealing DNA during the process of nucleotide excision repair and recombinant fragments.
Explain elongation stage of replication â you answer should include a discussion of leading strand, lagging strand, Okazaki pieces and RNA primer. Primase adds primer near inside of fork, DNA polymerase III adds nucleotides 5â-3â moving away from fork. After catching up to previous primer, DNA polymerase III must detach and move further into the expanding fork, after primase has added another primer deeper inside the fork.