AQA Biology 11.1 replication of DNA

Question	Answer
what is nuclear division?	the process by which the nucleus divides
what are the two types of nuclear division?	-meiosis -mitosis
what is cell division?	follows nuclear division and is the process where the entire cell divides
what must happen before a nucleus can divide?	DNA must be replicated
why must the DNA replicate?	so all the daughter cells have the genetic info to produce the enzymes and other proteins they need.
which model is universally accepted for DNA replication?	semi-conservative replication
how many requirements are there for DNA replication to occur?	4
what are the requirements?	-the 4 types of nucleotide, each with their bases of A,G,C and T must be present -both strands of DNA must act as a template for the attachment of these nucleotides -DNA polymerase (enzyme) is needed to catalyse the reaction -a source of chemical energy
which enzyme breaks up the hydrogen bonds linking the base pairs?	DNA helicase
what does DNA helicase cause the double helix to do?	separate into its two strands and unwinds
what then happens to each exposed polynucleotide?	acts as a template which attracts complementary nucleotides
what is used to activate the nucleotides?	energy - ATP
what joins the activated nucleotides together?	the enzyme DNA polymerase
what does each new DNA molecule contain?	one original strand and one new strand.

Resource summary

	Created by Charlotte Hewson over 9 years ago