Pre-module stuff (Important)

Question 1

What are the 3 main components of DNA?

Answer 1

• Sugar
• Base
• Phosphate backbone

Question 2

What bonds form between the bases in DNA?

Answer 2

Hydrogen

Question 3

What bonds form between the sugars in DNA?

Answer 3

Phosphate bonds - this forms the sugar phosphate backbone

Question 4

In what way are DNA strands arranged with each other?

Answer 4

In an antiparallel direction from the 5’ to the 3’ end

Question 5

What is the minor groove in DNA?

Answer 5

Where the sugar phosphate backbones are far apart

Question 6

What is the major groove in DNA?

Answer 6

Takes place where the sugar phosphate backbones are close together

Question 7

What are the components of a base unit?

Answer 7

• Pentose sugar
• Phosphate
• Purine or pyramidine base (nitrogenous bases)

Question 8

YOU MUST LEARN HOW TO DRAW A BASE

Answer 8

GO TO THE SLIDES

Question 9

What is the difference between the purines & the pyrmidines?

Answer 9

Purines have a 2 ringed structure whereas pyrimidines have only 1 ring which the bonds form on

Question 10

What are the Purines?

Answer 10

Adenine & Guanine

Question 11

What are the Pyrimidines?

Answer 11

Cytosine, Thymine (DNA) & Uracil (RNA)

Question 12

What is the difference between ribose & deoxyribose?

Answer 12

Deoxyribose has no hydroxyl bond

(Bottom right bond has H rather than OH)

Question 13

What is a nucleoSide vs a nucleoTide?

Answer 13

Nucleoside = sugar & base

Nucleotide = sugar, base & phosphate

Question 14

Which base pairs match up with each other?

Answer 14

A –> T (U)

G –> C

(Complementary base pairing)

Question 15

What are the 3 forms of DNA?

Answer 15

A = right helix
B = right
Z = left

Question 18

What are the characteristics of A DNA?

Answer 18

• Right helix
• 11 base pairs per turn
• 2.6 (Å) = distance between base pairs
• 23 (Å) = diameter of helix

Question 19

What are the characteristics of B DNA?

Answer 19

• Right helix
• 10 base pairs per turn
• 3.4 (Å) = distance between base pairs
• 19 (Å) = diameter of helix

Question 20

What are the characteristics of Z DNA?

Answer 20

• Left helix
• 12 base pairs per turn
• 3.7 (Å) = distance between base pairs
• 18 (Å) = diameter of helix

Question 21

Describe the role of B DNA?

Answer 21

• Common type od DNA found in cells
• Large major groove
• Some protgeins can ‘read’ the base seq in the major groove

Question 22

What is the nucleosome?

Answer 22

The subunit of chromatin

Question 23

What is chromatin

Question 24

What is the protein start codon base sequence?

Answer 24

ATG

Question 24

What are the main componenets of a eukaryotic gene?

Answer 24

• RNA starts
• Protein stat codon (ATG)
• Introns (not in mRNA) & exons (in mRNA)
• Protein stop codon (TAG, TAA, TGA)
• RNA end

Question 25

What is the protein stop codon base sequence?

Answer 25

TAG, TAA, TGA

Question 27

Got to slide 13 promoter regions

Answer 27

ddd