Chapter 3

Question 1

What is the process that converts DNA into RNA?

Answer 1

Transcription

Question 2

What is the process that converts RNA into proteins?

Answer 2

Translation

Question 3

What is the difference between a nucleotide and a nucleoside?

Answer 3

A nucleoside does not contain a phosphate group (only sugar and base)

Question 4

What is a nucleotide made up of?

Answer 4

Sugar, nitrogenous base, phosphate

Question 5

What is the difference between Ribose and Deoxyribose?

Answer 5

Ribose has a 2’ OH – Deoxyribose only has a 2’ H’s

Question 6

What is more stable: DNA or RNA? Why?

Answer 6

DNA; the 2’ OH on RNA makes it much more unstable than DNA that only has 2’ H’s

Question 7

List the pyrimidines:

Answer 7

Cytosine
Uracil
Thymine

Question 8

List the purines:

Answer 8

Adenine
Guanine

Question 9

What is the structural difference between purines and pyrimidines?

Answer 9

Pyrimidines are a single-ring, purines are a double-ring

Question 10

Describe Adenine:

Answer 10

Double nitrogenous ring with a primary amine on carbon 6

Question 11

Describe Guanine:

Answer 11

A double nitrogenous ring with a primary amine on carbon 2 and a carbonyl on carbon 6 that has caused the double bond to be removed and Nitrogen 1 to be protonated

Question 12

Describe Cytosine:

Answer 12

Single nitrogenous ring with a primary amine on carbon 4 and a carbonyl on carbon 2 (losing the double bond with nitrogen 1)

Question 13

Describe Uracil:

Answer 13

Single nitrogenous ring with a carbonyl on carbon 2 and 4, and a protonated nitrogen 3 between them

Question 14

Describe Thymine:

Answer 14

Single nitrogenous ring with a carbonyl on carbon 2 and 4, a protonated nitrogen 3, and a methyl on carbon 5
**Uracil with a methyl

Question 15

How many hydrogen bonds form between Adenine and Thymine?

Answer 15

2 hydrogen bonds

Question 16

How many hydrogen bonds form between Guanine and Cytosine?

Answer 16

3 hydrogen bonds

Question 17

What tautomer dominates for the nitrogenous bases?

Answer 17

Keto

Question 18

Why is ATP to ADP a spontaneous reaction?

Answer 18

Losses a larger leaving group
ATP has more limited resonance

Question 19

What supplies chemical energy?

Answer 19

Phosphoanhydride bonds

Question 20

What does ATP supply energy for?

Answer 20

Metabolism

Question 21

What does GTP supply energy for?

Answer 21

Protein synthesis

Question 22

What does CTP supply energy for?

Answer 22

Lipid synthesis

Question 23

What does UTP supply energy for?

Answer 23

Carbohydrate metabolism

Question 24

How are nucleic acids read and put together?

Answer 24

5’ –> 3’

Question 25

What is the structure of DNA?

Answer 25

Antiparallel double helix

Question 26

What type of helix is DNA?

Answer 26

Right-handed

Question 27

What is the diameter of DNA?

Answer 27

2 nm

Question 28

How does DNA replicate?

Answer 28

Semi-conservative

Question 29

What prevents tRNA hydrolysis?

Answer 29

Cloverlike structure from 3 hairpin loops

Question 30

What bond holds together protein chains (amino acids)?

Answer 30

Peptide bonds

Question 31

How are new amino acids added to an existing chain in a ribosome?

Answer 31

The new amino acid NH3 binds to the existing carboxylic acid

Question 32

What is the function of restriction endonuclease?

Answer 32

Cleave DNA at specific sites

Question 33

What DNA technique creates sticky and blunt ends? What is the difference between the two?

Answer 33

Restriction endonuclease Sticky ends have an overhang, blunt ends are flat

Question 34

What is the function of gel electrophoresis?

Answer 34

Separate DNA by size

Question 35

Explain how gel electrophoresis works:

Answer 35

DNA is loaded into a gel and moves toward the positively charged electrode -- smaller segments moving faster

Question 36

What charge does DNA have? Why?

Answer 36

Negative Phosphate group

Question 37

What is the function of Sanger sequencing?

Answer 37

Sequence the specific base pairs from a strand of DNA

Question 38

How does Sanger sequencing work?

Answer 38

Some normal nucleic acids and some fluorescing ones are added with a template plus primer; the nucleic acids are added and stop when they get a fluorescing one which creates different sizes that can be read to tell us the specific amino acid sequence