Nucleic Acids

Question 1

Who first isolated DNA and what was it called

Answer 1

Friedrich Miescher; called it nuclein

Question 2

Nucleic acids are linear ______________ made by connecting nucleotides via ________________________ bonds

Answer 2

polymers; phosphodiester

Question 3

What are the components of a nucleotide

Answer 3

sugar, base, phosphate group

Question 4

The sugar and phosphates form a _________________ for the bases

Answer 4

backbone (sugar phosphate backbone)

Question 5

RNA contains… (type of sugar)

Answer 5

D-ribose

Question 6

DNA contains… (type of sugar)

Answer 6

D-2-deoxyribose

Question 7

DNA and RNA sugars are in the _________________ form

Answer 7

b-furanose

Question 8

What are the pyrimidines

Answer 8

cytosine and thymine (replaced with uracil in RNA)

Question 9

What are the purines

Answer 9

adenine and guanine

Question 10

Why are purines and pyrimidines considered heterocycles

Answer 10

they contain non-carbon atoms in their rings (nitrogen)

Question 11

The purines are _______________ rings (think how many rings)

Answer 11

bicyclic (2 rings)

Question 12

What are tautomeric forms

Answer 12

the shifting of one H atom to give the molecule a new form

Question 13

What does the OH group undergo in tautomeric shifting

Answer 13

keto/enol tautomerism

Question 14

What does the NH2 group undergo in tautomeric shifting

Answer 14

amino/imino tautomerism

Question 15

What is the shift from enol to keto

Answer 15

-OH to =O

Question 16

What is the shift from amino to imino

Answer 16

-NH2 to =NH

Question 17

Base + Sugar (no phosphate) =

Answer 17

nucleoside

Question 18

Base + sugar + phosphate =

Answer 18

nucleotide

Question 19

What is the special type of glycoside found in nucleic acids

Answer 19

nucleoside

Question 20

The glycosidic bond in nucleosides is also sometimes called the ______________ bond to account for the C-N linkage

Answer 20

glycosilic

Question 21

The NH at position ______ of purines link to the anomeric carbon of ribose/deoxyribose

Answer 21

9

Question 22

The NH at position ______ of pyrimidines link to the anomeric carbon of ribose/deoxyribose

Answer 22

1

Question 23

Nucleotides are just ________________ nuceleosides

Answer 23

phosphorylated

Question 24

A phosphate group bridges between the _______ OH of one nucleotide unit, and the _________ OH of another, forming a ___________________ linkage

Answer 24

between 5’ OH and 3’ OH
creating a phosphodiester linkage

Question 25

What are the 5’ and 3’ ends lacking

Answer 25

nucleotides
5’ end lacks a nucleotide at 5’ position
3’ end lacks a nucleotide at 3’ position

Question 26

The phosphate groups are _____________ and ______________ charged at pH 7

Answer 26

ionized and negatively charged

Question 27

Under alkaline conditions, what happens in relation to RNA hybridization

Answer 27

the 2’ OH group reacts with the phosphate on the 3’ breaking the phosphodiester linkage