Bio 30 Unit 2 Booklet 1

Question 1

what is a nucleotide

Answer 1

subunits of DNA which are composed of
five carbon sugar
phosphate
nitrogen base

Question 2

what is the backbone and teeth of DNA and how are they bonded

Answer 2

backbone - alternating phosphate and sugar groups COVALENTLY bonded
teeth - nitrogen bases HYDROGEN bonding

Question 3

DNA replication - what enzyme breaks apart the hydrogen bonds in the two strands of DNA

Answer 3

Helicase

Question 4

What holds apart the two ‘unzipped’ DNA strands

Answer 4

SSB - Single Strand Binding proteins

Question 5

What causes free floating bases to bind to the chain

Answer 5

DNA Polymerase III

Question 6

What is the issue of DNA Ploymerase III? And its solutions?

Answer 6

it does not know where to begin - RNA primer gives starting point (RNA primer made by RNA primase)
only moves on 5’ to 3’ - lagging strand is made in okazaki fragments

Question 7

what are okazaki fragments

Answer 7

the lagging strand is built in these fragments in order to overcome the issue of DNA polymerase moving from 5’ to 3’. RNA primer will be spaced out for the DNA Polymerase III to fill it in backwards from the direction of helicase.

Question 8

What is the role of ligase in DNA replication

Answer 8

glues together lagging and leading strands

Question 9

Protein synthesis is made of what two sections?

Answer 9

Transcription - splitting DNA and making a copy of mRNA
then
Translation - proteins are made by tRNA bringing amino acids as described by the mRNA