Chapter 2: Nucleic Acids and DNA structure

Question 1

What are the building blocks of nucleic acids?

Answer 1

nucleotides

Question 2

What are the 3 parts of a nucleotide?

Answer 2

• phosphate group
• pentose (5 carbon sugar, ribose or deoxyribose)
• nucleobase

Question 3

What is the difference between deoxyribose and ribose?

Answer 3

• the 2’ end has an OH group instead of an H group in RNA

Question 4

Name the 2 types of nitrogenous bases.

Answer 4

pyrimidines and purines

Question 5

How many rings do purines have? What nitrogenous bases are included here?

Answer 5

• 2 rings
• Adenine and Guanine

Question 6

How many rings do pyrimidines have? What nitrogenous bases?

Answer 6

• 1 ring
• Thymine, cytosine and Uracil

Question 7

What type of bonds join nucleotides together?

Answer 7

• covalent bonds

Question 8

Nucleotides are joined together to form a strand of __ __.

Answer 8

nucleic acid

Question 9

What is the function of DNA?

Answer 9

• stores the genetic info of all cellular organisms

Question 10

What is the function of RNA?

Answer 10

• Involved in communicating the instructions stored in DNA

Question 11

How are RNA viruses different?

Answer 11

• RNA directly goes to get transcribed (I think instead of using DNA as a template strand)

Question 12

What is the structure of DNA? (3)

Answer 12

• Each strand is built from a sugar phosphate backbone
• two strands are held together by hydrogen bonds between nitrogenous bases
• forms the double helix

Question 13

The order of bases in DNA is specific and forms the ____ instructions for the organism.

Answer 13

• Genetic
  ie. genes

Question 14

What direction is DNA synthesized?

Answer 14

5’ to 3’ (based on position of carbon)

Question 15

Which needs a higher temperature to break its bond: GC or AT?

Answer 15

GC because it has 3 H bonds