Chapter 7, Structure and Isolation of DNA

Question 1

What are Chargaff’s Rules?

Answer 1

The nitrogenous bases that are present in DNA occur in a constant ratio:

The amounts of adenine always equal those of thymine, and the amounts of cytosine always equal those of guanine.

Question 2

Who was responsible for determining the actual structure of DNA?

What was that structure?

Answer 2

Franklin, Watson, and Crick

A double helix

Question 3

________ are the monomers of nucleic acids.

Answer 3

Nucleotides

Question 4

A nucleotide consists of what 3 components?

Answer 4

1 - a phosphate group

2 - a pentose or five-carbon sugar

3 - one of the nitrogenous bases

Question 5

What are the 2 groups of nitrogenous bases?

Answer 5

1 - Pyrimidines

2 - Purines

Question 6

What are the names of the 2 purines?

How many rings do they have?

Answer 6

1 - Adenine

2 - Guanine

They both have 2 rings

Question 7

What are the names of the 2 pyrimidines relivant to DNA?

How many rings do they have?

Answer 7

1 - Cytosine

2 - Thymine

Question 8

What are the complementary base pairs?

Answer 8

A = T

2 hydrogen bonds

C =- G

3 hydrogen bonds

Question 9

What is a phosphodiester linkage?

Answer 9

A series of bonds connecting 2 different sugar molecules