Quiz 1

Question 1

Approximately how much of the human genome codes for proteins?

Answer 1

~2%

Question 2

How much energy is in a double helix hydrogen bond?

Answer 2

~2-3 kcal/mol

Question 3

Watson-Crick base pairs exhibit what type of geometry?

Answer 3

isomorphous geometry

Question 4

In B-form DNA, one helical turn equals how many degrees?

Answer 4

360

Question 5

In B-form DNA, how base pairs per turn are there?

Answer 5

10.5

Question 6

What is the value for the twist angle in B-form DNA?

Answer 6

36.1

Question 7

How wide is the minor groove in B-form DNA?

Answer 7

6 angstroms

Question 8

How wide is the major groove in B-form DNA?

Answer 8

12 angstroms

Question 9

What is the value for the axial rise in B-form DNA?

Answer 9

3.4 angstroms

Question 10

What is the value for the helix diameter in B-form DNA?

Answer 10

20 angstroms

Question 11

What is the value for the roll angle in B-form DNA?

Answer 11

0.6

Question 12

What is the value for the tilt angle in B-form DNA?

Answer 12

0

Question 13

What is the value for the propeller twist angle in B-form DNA?

Answer 13

11.1

Question 14

What is the value for the propeller twist angle in A tract DNA?

Answer 14

25

Question 15

What is rise?

Answer 15

distance between adjacent base pairs

Question 16

What is pitch?

Answer 16

distance per complete turn

Question 17

What is twist?

Answer 17

angle of rotation between adjacent base pairs

Question 18

What is tilt?

Answer 18

angle of base pairs to normal of helical axis

Question 19

What is roll?

Answer 19

angle between:

1. line perpendicular to axis
2. line between adjacent base pairs

Question 20

What is propeller twist?

Answer 20

angle between planes of a 2 paired bases

Question 21

What is slide?

Answer 21

translocation of base pair along Y axis relative to helical axis

Question 22

What is the sugar pucker of A-form DNA?

Answer 22

3’ endo

Question 23

What is the sugar pucker of B-form DNA?

Answer 23

2’ endo

Question 24

What is the sugar pucker of Z-form DNA?

Answer 24

2’ endo for C

3. endo for G

Question 25

What is the conformation of the glycosidic linkage in nucleoside purines?

Answer 25

equilibrium between syn and anti

Question 26

What is the conformation of the glycosidic linkage in nucleoside pyrimidines?

Answer 26

anti

Question 27

What is the conformation of the glycosidic linkage in the nucleic acids?

Answer 27

fixed - anti

Question 28

Describe the major and minor groove of A-form DNA.

Answer 28

Major groove: narrow and very deep | Minor groove: very broad and shallow

Question 29

Describe the major and minor groove of B-form DNA.

Answer 29

Major groove: wide and quite deep | Minor groove: narrow and quite deep

Question 30

Describe the major and minor groove of Z-form DNA.

Answer 30

Major groove: flat | Minor groove: very narrow and deep

Question 31

What is rise for A-form DNA?

Answer 31

2.3 angstroms

Question 32

What is the helix diameter for A-form DNA?

Answer 32

25.5 angstroms

Question 33

What is the conformation of the glycosidic linkage in A-form DNA?

Answer 33

anti

Question 34

What is the conformation of the glycosidic linkage in B-form DNA?

Answer 34

anti

Question 35

What is the conformation of the glycosidic linkage in Z DNA?

Answer 35

anti for C,T | syn for G

Question 36

How many base pairs per turn in A-form DNA?

Answer 36

11

Question 37

How many base pairs per turn in Z-form DNA?

Answer 37

12

Question 38

What is the pitch per turn in A-form DNA?

Answer 38

25.3 angstroms

Question 39

What is the pitch per turn in Z-form DNA?

Answer 39

45.6 angstroms

Question 40

What is the tilt of base pairs in A-form DNA?

Answer 40

19 degrees

Question 41

What is the tilt of base pairs in Z-form DNA?

Answer 41

9 degrees

Question 42

What is the helix diameter of Z-form DNA?

Answer 42

18.4 angstroms

Question 43

What is the charge of a nucleotide at pH < 1?

Answer 43

+2 0

Question 44

What is the charge of a nucleotide at pH = 3.9?

Answer 44

0 -1

Question 45

What is the charge of a nucleotide at pH = 6.8?

Answer 45

-1 -2

Question 46

What is the charge of a nucleotide at pH > 12.5?

Answer 46

-2 -3