Lesson 18: Nucleic Acid Structure

Question 1

What is the monomer of nucleic acids?

Answer 1

Nucleotides

Question 2

What are the polymers of nucleic acids?

Answer 2

DNA: deoxyribonucleic acid
RNA : ribonucleic acid

Question 3

What does DNA do?

Answer 3

Stores the hereditary information of a cell, genes are discrete units of hereditary information consisting of a specific nucleotide sequence

Question 4

What does RNA do?

Answer 4

Assist in protein production

Question 5

What are the components of a nucleotide?

Answer 5

Phosphate group, 5-carbon sugar (pentose), nitrogenous base (cytosine, guanine, adenine, thymine (DNA only) and uracil (RNA only)

Question 6

What does deoxyribose lack in the pentose sugars?

Answer 6

Lacks a hydroxyl group on the second carbon

Question 7

What are nitrogenous bases?

Answer 7

Carbon rings that also contain nitrogen

Question 8

What are pyrimidines in nitrogenous bases?

Answer 8

Cytosine, thymine (DNA), and uracil (RNA)

Question 9

What are purines in nitrogenous bases?

Answer 9

Adenine and guanine
Purines are PURE as gold so you want two of them

Question 10

What are the complementary base pairings?

Answer 10

T:A (DNA), U:A (RNA)
C:G (both)

Question 11

What is the numbering carbons?

Answer 11

Numbering of carbons in the sugar is important. The carbon double bonded to oxygen (the carbonyl group) is #1

Question 12

How do you form a ring for carbons?

Answer 12

A covalent bond forms between the hydroxyl group on the 4th carbon and the carbonyl group on the first carbon. Because nucleotides are complex, sugar carbons are noted with a ‘ (prime). This differentiated the carbons of the sugar from the carbons in the nitrogenous base

Question 13

What is a nucleoside?

Answer 13

Sugar+base=nucleoside
A dehydration reaction between the nitrogenous base and the 1’ C of the pentose links the base to the sugar

Question 14

What is the phosphate group?

Answer 14

Inorganic phosphate can form a covalent bond with the 5’ carbon of the nucleoside by a dehydration reaction

Question 15

What can a phosphate group make on a nucleoside?

Answer 15

Nucleotide (monomer of DNA and RNA)

Question 16

What are polynucleotides?

Answer 16

Dehydration reaction between:
The phosphate group on one nucleotide
The hydroxyl on the 3’ carbon of a second nucleotide

These link monomers together

Question 17

How does DNA usually exist?

Answer 17

As two strands of polynucleotides

Question 18

What are complementary bases in the DNA structure?

Answer 18

Pair between the two strands

Question 19

What is the double helix in the DNA structure?

Answer 19

Two strands form a double helix

Question 20

What is anti-parallel in DNA structure?

Answer 20

The strands run in opposite 5’ to 3’ directions

Question 21

What does RNA usually exist as?

Answer 21

RNA usually exists as a single polynucleotides strand

Question 22

What are other aspects of the RNA structure?

Answer 22

Bases in one part of the strand can hydrogen bond to complimentary bases in another part of the strand. Can create complex structures

Question 23

What is the difference between the genetic materials of DNA and RNA?

Answer 23

DNA
double stranded
Only found in the nucleus
Contains A,G, C, and T
Sugar= deoxyribose

RNA
Single stranded
Found both inside and outside of the nucleus (cytoplasm)
Contains A,G, C, and U
Sugar= ribose

Question 24

What is DNA replication in short?

Answer 24

DNA makes a copy of itself for cell division (nucleus)

Question 25

What is DNA transcription in short?

Answer 25

DNA creates messenger RNA (nucleus)

Question 26

What is RNA translation in short?

Answer 26

RNA is translated to produce a protein (cytoplasm)