Nucleic Acids and DNA Structure

Question 1

What are the three components compromised in each nucleotide?

Answer 1

Nitrogenous base
phosphate group
pentose sugar

Question 2

Where is DNA found in Eukaryotes? How about Prokaryotes?

Answer 2

1. Nucleus
Organelles
chloroplasts
mitochondria
2. DNA is not enclosed in a membrane envelope

Question 3

What is the difference between a DNA nucleotide and an RNA nucleotide?

Answer 3

DNA has a deoxyribose sugar (H) on the 2 carbon

RNA has a ribose sugar (OH) on the 2 carbon

Question 4

What is the monomer of a nucleic acid?

Answer 4

nucleotide

Question 5

What is the difference between pyrimidines and purines

Answer 5

Pyrimidines have one ring

Purines have 2 rings

Question 6

Explain DNA’s double helix’s antiparallel orientation

Answer 6

The 5 carbon end of one strand faces the 3 carbon end of the other strand

Question 7

Overview of the DNA double helix structure

Answer 7

• phosphate and sugar form the backbone

- bases are inside linked through H bonds

Question 8

Base-complementary rule and which bond will be harder to break?why?

Answer 8

Only certain base pairings are allowed…
A-T or U if RNA
C-G

Question 9

Describe the difference between the 5’ end and the 3’ end of a nucleotide.

Answer 9

On the 5’ end the phosphate is linked to the 5’ carbon

3’ end phosphate is on 3’carbon

Question 10

What are the main structural differences between RNA and DNA?

Answer 10

DNA: double helix, AG (purines) TC(pyrimidines), deoxyribose sugar, remains in nucleus
RNA: single strand, AG (purines), UC(pyrimidines), leaves nucleus

Question 11

What are the differences in function between DNA and RNA?

Answer 11

DNA: controls all cellular activity in the cell
RNA: aids with protein synthesis

Question 12

What do DNA and RNA dictate?

Answer 12

DNA dictates mrNA structure through transcription

RNA dictates protein structure through translation

Question 13

In a normal double strand why are certain purine base-paired with certain pyrimidines?

Answer 13

Only certain purine-pyrimidine pairs have the same geometry

Question 14

Major groove versus minor groove

Answer 14

Major is very big and allows for sequence specific binding

minor is too small to get into and bind specifically

Question 15

Why is DNA Replication considered to be semi conservative?

Answer 15

Because 2 of the parent strands act as a template for new DNA to be synthesized