DNA

Question 1

What is DNA a polymer of?

Answer 1

Nucleotides.

Question 2

What are the components of a DNA nucleotide?

Answer 2

Deoxyribose, a phosphate group, and an organic/nitrogenous base.

Question 3

What bond joins nucleotides in DNA?

Answer 3

Phosphodiester bond.

Question 4

What structure is formed by two DNA strands held by hydrogen bonds?

Answer 4

Double helix.

Question 5

Which bases pair in DNA?

Answer 5

Adenine with Thymine, and Cytosine with Guanine.

Question 6

What reaction forms a phosphodiester bond?

Answer 6

Condensation.

Question 7

What parts of the nucleotides form the phosphodiester bond?

Answer 7

Phosphate and deoxyribose.

Question 8

Which enzyme catalyses phosphodiester bond formation?

Answer 8

DNA polymerase.

Question 9

What does the sugar-phosphate backbone provide?

Answer 9

Strength and stability; protects bases and hydrogen bonds.

Question 10

Why is DNA a long molecule?

Answer 10

To store lots of information.

Question 11

Why is DNA coiled into a helix?

Answer 11

To be compact.

Question 12

What allows DNA to code for proteins?

Answer 12

Base sequence.

Question 13

Why is DNA double stranded?

Answer 13

So replication can occur semi-conservatively; strands act as templates.

Question 14

What allows accurate DNA replication?

Answer 14

Complementary base pairing (A-T and G-C).

Question 15

Why can DNA strands unzip during replication?

Answer 15

Weak hydrogen bonds.

Question 16

What makes DNA strong and stable?

Answer 16

Many weak hydrogen bonds.

Question 17

What sugar does DNA contain?

Answer 17

Deoxyribose.

Question 18

What sugar does mRNA contain?

Answer 18

Ribose.

Question 19

What base is in DNA but not mRNA?

Answer 19

Thymine.

Question 20

What base is in mRNA but not DNA?

Answer 20

Uracil.

Question 21

Which is longer: DNA or mRNA?

Answer 21

DNA.

Question 22

Which is double stranded: DNA or mRNA?

Answer 22

DNA.

Question 23

Which is single stranded: DNA or mRNA?

Answer 23

mRNA.

Question 24

Which molecule has hydrogen bonds: DNA or mRNA?

Answer 24

DNA.

Question 25

Does mRNA have complementary base pairing?

Answer 25

No.

Question 26

What happens first in semi-conservative replication?

Answer 26

Strands separate and hydrogen bonds break.

Question 27

What enzyme breaks hydrogen bonds in DNA?

Answer 27

DNA helicase.

Question 28

What do both DNA strands act as during replication?

Answer 28

Templates.

Question 29

What joins to the template strands during replication?

Answer 29

Free nucleotides.

Question 30

What ensures specific base pairing in replication?

Answer 30

Hydrogen bonding between bases.

Question 31

Which enzyme joins new nucleotides in replication?

Answer 31

DNA polymerase.

Question 32

What bond does DNA polymerase form?

Answer 32

Phosphodiester bond.

Question 33

What kind of reaction does DNA polymerase catalyse?

Answer 33

Condensation.

Question 34

What does each new DNA molecule contain after replication?

Answer 34

One old strand and one new strand.

Question 35

What is the name of this replication method?

Answer 35

Semi-conservative replication.

Question 36

Which bonds are broken to separate DNA strands?

Answer 36

Hydrogen bonds between base pairs.

Question 37

What are two features of DNA that allow replication?

Answer 37

Weak hydrogen bonds (for strand separation); two strands (for templates).

Question 38

What allows accurate replication in DNA?

Answer 38

Complementary base pairing.

Question 39

Who proposed the models of DNA structure and replication?

Answer 39

Crick and Watson.