12.2 The Structure Of DNA

Question 1

DNA is a _____ ______ made of ______

Answer 1

Nucleic acid, nucleotides

Question 2

What bonds form between nucleotides

Answer 2

Hydrogen bonds

Question 3

How many parts is DNA made of

Answer 3

3

Question 4

What are the three parts of DNA

Answer 4

Nitrogenous bases phosphate groups and a five carbon sugar

Question 5

Nitrogenous bases have a chemical like structure that allow them to

Answer 5

Absorb UV light

Question 6

What are the chemicals in nitrogenous bases that allow them to absorb UV light beneficial for

Answer 6

This allows scientists to measure the amount of DNA by measuring the amount of light it absorbs at a wavelength of 260 nm

Question 7

Purine

Answer 7

Two ring nitrogenous base

Question 8

Pyrimidine

Answer 8

One ring nitrogenous base

Question 9

What bases are purines

Answer 9

Adenine and guanine

Question 10

What bases are pyrimidines

Answer 10

Cytosine and thymine

Question 11

Where are the covalent bonds in a DNA molecule

Answer 11

The nucleotides of a strand of DNA are joined by covalent bonds between the sugar one nucleotide and the phosphate group of the next

Question 12

Chargaff’s rule

Answer 12

Adenine always bonds with thymine and guanine always bonds with cytosine

Question 13

How did Chargaff create his rule

Answer 13

He discovered his rule because of the percentages of adenine and thymine and guanine and cytosine are always almost identical in any sample of DNA

Question 14

Rosalind Franklin

Answer 14

Used x-ray diffraction to study the structure of the DNA moleculef

Question 15

What was Rosalind Franklins job

Answer 15

X-ray crystallographer 

Question 16

Who did Franklin work under

Answer 16

Wilkins

Question 17

How did Franklin get a picture of DNA

Answer 17

She purified a large amount of DNA strand of the DNA fiber is in a thin glass tube until they were parallel and shot powerful concentrated x-ray PMs and recorded the scattered patterns of the extras on a film

Question 18

What does x-ray diffraction pattern reveal

Answer 18

It revealed a helix structure of two strands with nitrogenous bases in the center

Question 19

Helix

Answer 19

Extended Spiral chain of units in a protein nucleic acid and other macromolecules

Question 20

James Watson and Francis crick

Answer 20

Made 3-D models of DNA with cardboard and wire by using Franklins x-ray pattern they made a double helix in which two strands of nucleotide sequences were wound around each other

Question 21

Watson and crick published their work in the paper true or false

Answer 21

True

Question 22

What was the name of Watsons book

Answer 22

The double helix

Question 23

Who won the Nobel prize

Answer 23

Watson and crick and they share the prize with Wilkins who gave them Franklins work

Question 24

The double helix model explains ______ _______ and how the two strands of DNA are held together

Answer 24

Chargaff’s rule

Question 25

Antiparallel

Answer 25

Two strands of DNA run in opposite directions

Question 26

What allows the nitrogenous bases to come in contact in the center of the molecule upside down in relation to one another

Answer 26

The anti-parallel structure

Question 27

Nitrogenous bases are hold together by

Answer 27

Hydrogen bonds

Question 28

Why are the hydrogen bonds between
Nitrogenous bases very important

Answer 28

Because the bond is weak which allows for the DNA to break which is very important for one of its functions

Question 29

Base pairing

Answer 29

Nearly perfect fit between A and T and G and C

Question 30

The sides of DNA are made of

Answer 30

Alternating deoxyribose and phosphate

Question 31

How many hydrogen bonds do guanine and cytosine have

Answer 31

3

Question 32

How many hydrogen bonds to adenine and thymine have

Answer 32

2

Question 33

Anti-parallel structure

Answer 33

One strand runs from five prime to three prime in the other runs from three prime to five prime