key area 1.1 - structure and organisation of dna

Question 1

What are the three structures that make up a nucleotide?

Answer 1

Deoxyribose sugar, Phosphate, and nitrogenous bases

Question 2

How is the deoxyribose sugar joined to the phosphate molecule?

Answer 2

With strong sugar phosphate bonds

Question 3

What are the organic bases joined by?

Answer 3

Weak hydrogen bonds

Question 4

Which prime end does dna run from and go to?

Answer 4

DNA runs from the 5’ (five prime) end to the 3’ (prime) end

Question 5

Are the strands parallel or anti-parrallel and why?

Answer 5

The strands are anti-parallel because they travel in different directions

Question 6

Name the four complementary bases and which base they pair with

Answer 6

adenine + thymine and cytosine + guanine

Question 7

Name a difference between prokaryotes and eukaryotes

Answer 7

Prokaryotic cells do not have a membrane bound nucleus whereas eukaryotic cells have a membrane bound nucleus

Question 8

How is DNA arranged in eukaryotic cells

Answer 8

Inside the nucleus DNA is arranged into linear chromosomes

Question 9

How is DNA stored a prokaryotic cell?

Answer 9

DNA is stored in a single circular chromosome and in smaller circular plasmids

Question 10

In eukaryotic cells what is proteins is DNA packed with?

Answer 10

DNA is packed with associated proteins called histone proteins

Question 11

What do eukaryotic cells have that prokaryotic cells don’t have?

Answer 11

Eukaryotic cells have circular chromosomes in their mitochondria and chloroplasts