DNA Replication

Question 1

what are the 3 “steps” in DNA replication?

Answer 1

1. there is a parent molecule (strand)
2. Hydrogen bonds holding the two DNA strands together break and the strands separate
3. Each old strand is template that determines the
   order of nucleotides along new complementary
   strand

Question 2

what do daughter DNA strands consist of?

Answer 2

consist of one “old” parent strand, and one new strand

Question 3

what are the 3 main macromolecules involved in DNA replication?

Answer 3

1. Helicase
2. DNA polymerase
3. RNA primer

Question 4

what does helicase do?

Answer 4

untwists and separates the two DNA strands

-like the handle part of a zipper

Question 5

what does DNA polymerase do? what does it require?

Answer 5

adds new nucleotides to 3’ end of nucleotide chain

-requires pre-existing polynucleotide to build off of –> RNA primer

Question 6

what does RNA primer do?

Answer 6

it adds a short sequence of RNA to a strand so that the DNA polymerase has something to build off of

Question 7

in which direction does a new DNA strand elongate in?

Answer 7

New DNA strand can elongate only in 5’ to 3’ direction (builds on 3’ side)

Question 8

what is the leading strand?

Answer 8

the template strand of DNA of which polymerase can move along and synthesize new DNA continuously; moves in same direction as the unwinding DNA double helix

Question 9

what is the lagging strand?

Answer 9

the template strand of DNA of which polymerase moves in the opposite direction of the unwinding DNA double helix; DNA is synthesized as a series of fragments, which are joined together later

Question 10

the point at which helicase unzips the 2 DNA strands is:

Answer 10

the replication fork