Chapter 4 Nucleic Acids and RNA

Question 1

DNA stores ______ and is replicated using ______

Answer 1

genetic information, proteins

Question 2

RNA world hypothesis

Answer 2

proposition that at one point in evolution RNA store genetic information and catalyzed its own replication

Question 3

DNA

Answer 3

deoxyribosenucleic acid

Question 4

RNA

Answer 4

ribonucleic acid

Question 5

nucleic acids are polymers made up of…

Answer 5

monomers called nucleotides

Question 6

3 component of a nucleotide

Answer 6

1. phosphate group
2. five carbon sugar
3. nitrogenous base

Question 7

what are the monomers of RNA?

Answer 7

ribonucleuotides

Question 8

what are the monomers of DNA?

Answer 8

Add to dictionary

Question 9

what are the 4 possible nitrogenous bases for DNA?

Answer 9

cytosine, thymine, guanine, adenine

Question 10

what are the 4 possible nitrogenous bases for RNA?

Answer 10

cytosine, uracil, guanine, adenine

Question 11

difference between pyrimidines and purines?

Answer 11

purines have two rings from 9 atoms, while pyrimidines have a single ring of 6 atoms

Question 12

name the 3 pyrimidines

Answer 12

cytosine, uracil, thymine

Question 13

name the 3 purines

Answer 13

adenine, guanine

Question 14

explain the different in the sugar group of DNA and RNA an why it is significant

Answer 14

ribose in RNA has a hydroxide group bound to the 2’ on the carbon ring, while deoxyribose in DNA only has a hydrogen bound to the 2’. the OH group is much more reactive, so RNA can catalyze more reaction while DNA remains much more stable

Question 15

to which points on the carbon sugar do the phosphate groups bind to form the backbone?

Answer 15

the 5’ and 3’

Question 16

to which point on the carbon sugar do the nitrogenous bases bind?

Answer 16

the 1’

Question 17

explain the phosphodiester linkage between the 3’ on the sugar group and the phosphate group. what type of reaction occurs?

Answer 17

the O linked to the sugar binds to the P group, releasing OH and H, water, so this is a condensation reaction

Question 18

direction that sequences of bases are written

Answer 18

5’ to 3’

Question 19

direction that strands of DNA and RNA are replicated

Answer 19

5’ to 3’

Question 20

explain where the energy for polymerization comes from

Answer 20

adding 2 phosphates to a nucleotide (creating a nucleotide triphosphate) increases the potential energy. These become activated nucleotides, an example of this is ATP

Question 21

what is ATP

Answer 21

an activated ribonucleotide called adenine triphosphate, it carries a large amount of potential energy, the energy is released when the phosphates are released so the molecule can form more stable bonds

Question 22

Chargaffs rule(s)

Answer 22

A DNA molecule has an equal number of pyrimidines as purines, the # of A’s = # T’s, and the # of C’s = # of G’s

Question 23

Rosalind Frankilind and Maurice Wilkins

Answer 23

X ray crystallography, DNA has a regular structure, it is helical

Question 24

Watson and Crick

Answer 24

complementary base pairing between A-T and C-G, purine-pyrimidine pairs

Question 25

number of bond forms between base pairs

Answer 25

3 hydrogen bond between C-G, 2 hydrogen bonds between A-T

Question 26

antiparallel strand form:

Answer 26

double helix

Question 27

meaning of antiparallel strands

Answer 27

one runs 5’ to 3’, the other 3’ to 5’

Question 28

why double stranded structure of DNA is important for replication

Answer 28

both strands of DNA can act as a stable template for synthesis of new DNA

Question 29

how does hydrogen bonding effect the secondary structure of RNA?

Answer 29

the majority of the purine-pyrimidines bonds form with bases on the same strand, causing the RNA to fold over into a hairpin structure

Question 30

hairpin structure

Answer 30

RNA which has forms a double helix with an unpaired loop on one end

Question 31

RNA synthesis

Answer 31

1. complementary bases pair
2. copied strand polymerizes
3. template and copy separate
4. copy serves as a template
5. new copy polymerizes
6. new copy is identical to original template

Question 32

ribozymes

Answer 32

catalytic RNA, or RNA enzymes as they are capable of forming complex structure to react multiple ways