7-DNA Structure & Functions

Question 1

In how many and which conformations can the DNA be found?

Answer 1

It can be found in many conformations that include A-DNA, B-DNA, Z-DNA

Question 2

In what does the different conformations of DNA depend on?

Answer 2

• The hydration level
• DNA sequence
• the amount and direction of supercoiling
• Chemical modifications of the bases
• The type and concentration of metal ions
• The presence of polyamines in solution

Question 3

What distance do 5 billion bp and 5 thousand of DNA cover?

Answer 3

1 meter and 1.2mm respectively

Question 4

What are the sizes of:
Phage virus (number of bases)
E.coli bacteria(length of DNA)
Human cell(feet)

Answer 4

168 kb
1,100 mm
7.5 feet of DNA

Question 5

How much is 1 kb in bp?

Answer 5

1000 bp

Question 6

How much is 1Mb in bp?

Answer 6

1,000,000 bp

Question 7

With can we compare the DNA fit into the nucleus?

Answer 7

Equivalent to fitting 690 miles of movie film in a 30- square foot room\

Question 8

How much smaller doees the DNA become when being packaged?

Answer 8

2.3 million times smaller

Question 9

In which phase does the DNA replicate

Answer 9

In S-phase

Question 10

Which is the diameter of a histone?

Answer 10

30nm

Question 11

What is a histone?

Answer 11

DNA binding protein

Question 12

What does the histone octamer consist of?

Answer 12

1. 2 H2A
2. 2 H2B
3. 2 H3
4. 2 H4

Question 13

What does the nucleosome consist of?

Answer 13

1) Octameric histone core

2) 146 nucleotide-pair DNA double helix