1B DNA & RNA Start

Question 1

What is the function of DNA?

Answer 1

To store GENETIC INFORMATION

Question 2

What is the function of RNA?

Answer 2

Transfers the genetic information fron DNA to the RIBOSOMES

Question 3

What is the structure of a nucleotide?

Answer 3

> 1 Pentose sugar
1 Nitrogenous base
1 Phosphate group

Question 4

How are nuclotide joined together to form polynucleotides?

Answer 4

5, 3 phosphodiester bonds

Question 5

Describe the structure of DNA.

Answer 5

> 2 POLYNUCLEOTIDE CHAINS running ANTIPARALLEL to each other that is coiled into a DOUBLE HELIX
It contains DEOXYRIBOSE SUGAR and the nitrogenous bases, A, C, T and G

Question 6

Describe the structure of RNA.

Answer 6

> A SINGLE, SHORT polynucleotide strand

> It’s nucelotides contain RIBOSE sugar and the nitrogenous bases A, C, U and G

Question 7

Describe the process of semi-conservative replication.

Answer 7

> DNA HELICASE breaks teh HYDROGEN BONDS between the bases on the two polynucleotide strands
This unwinds the helix to form TWO SINGLE STARNDS

> These act as TEMPLATE STRANDS for a new strand to form. COMPLEMENTARY BASE PAIRING means DNA nucleotides are ATTRACTED to EXPOSED BASES on the original strands

> CONDENSATION REACTIONA join the nuclotides of the NEW strand together
This process is catalysed by DNA POLYMERASE
HYDROGEN BONDS then form between bases on the new and original strands

Question 8

Why is DNA replication referred to as semi-conservative?

Answer 8

ONE of the polynucleotide strands in each newly formed molecule are from the ORIGINAL DNA molecule