D1.1 HL only

Question 1

polymers

Answer 1

any of a class of natural or synthetic substances composed of very large molecules, called macromolecules, which are multiples of simpler chemical units called monomers

Question 2

monomers

Answer 2

atoms or small molecules that bond together to form more complex structures such as polymers

Question 3

nucleotides

Answer 3

basic building block of nucleic acids(RNA and DNA). A nucleotide consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA)

Question 4

phosphate group

Answer 4

a phosphorus atom bound to four oxygen atoms

Question 5

Condensation reaction

Answer 5

any of a class of reactions in which two molecules combine, usually in the presence of a catalyst, with elimination of water or some other simple molecule

Question 6

covalent bond

Answer 6

a chemical bond that involves the sharing of electrons to form electron pairs between atoms

Question 7

phosphodiester bonds

Answer 7

a covalent linkage between the phosphate of one nucleotide and the hydroxyl (OH) group attached to the 3′ carbon of the deoxyribose sugar in an adjacent nucleotide, forming what is known as the “sugar-phosphate backbone” of DNA

Question 8

anti-parallel

Answer 8

one strand runs in a 5’ to 3’ direction and the other runs in a 3’ to 5’ direction. This creates the twisting double helix structure of DNA.

Question 9

replication fork

Answer 9

the area where the replication of DNA will actually take place. There are two strands of DNA that are exposed once the double helix is opened

Question 10

helicase

Answer 10

enzymes that bind and may even remodel nucleic acid or nucleic acid protein complexes

Question 11

Leading strand

Answer 11

The strand that runs in the 5’ to 3’ direction in the replication fork

Question 12

Lagging strand

Answer 12

he strand of new DNA whose direction is opposite to the direction of the growing replication fork.

Question 13

RNA primers

Answer 13

a short segment of single-stranded RNA used as a binding site for DNA polymerase to initiate DNA replication. DNA polymerase is only able to add nucleotides to an existing nucleotide chain

Question 14

RNA primase

Answer 14

an enzyme that synthesizes short RNA sequences called primers

Question 15

Okazaki fragment

Answer 15

short sections of DNA formed at the time of discontinuous synthesis of the lagging strand during replication of DNA

Question 16

Topoisomerase

Answer 16

an essential enzyme that catalyzes the ATP-dependent negative super-coiling of double-stranded closed-circular DNA

Question 17

Single-stranded binding proteins (SSBPs)

Answer 17

a protein found in Escherichia coli (E.coli) bacteria, that binds to single-stranded regions of deoxyribonucleic acid (DNA)

Question 18

DNA polymerase III

Answer 18

an enzyme that synthesizes new DNA strandsby adding nucleotides to the 3’ end of a pre-existing or newly synthesized DNA

Question 19

DNA polymerase I

Answer 19

an enzyme that removes RNA primers and replaces the RNA nucleotides with DNA nucleotides

Question 20

DNA ligase

Answer 20

an enzyme that joins DNA strands through the formation of phosphodiester bonds in a process called DNA ligation

Question 21

hydrogen bonds

Answer 21

an interaction in which a hydrogen atom bridges two electronegative atoms

Question 22

base-pairing rules

Answer 22

A unit of two bases in a molecule of DNA or RNA. In DNA, adenine always pairs with thymine (A-T), and guanine always pairs with cytosine (G-C). RNA is the same, except that adenine always pairs withuracil(A-U)

Question 23

complementary DNA strand

Answer 23

Stand of DNA produced from base-pairing with nucleotides in the template DNA strand

Question 24

DNA template strand

Answer 24

The original strands of DNA act as a template for the synthesis of new strands of DNA