Key Area 1.1:The structure of DNA

Question 1

what are the three parts of a nucleotide?

Answer 1

• Base(nitrogenous)
• Sugar
• Phosphate

Question 2

why 3 prime end and 5 prime end?

Answer 2

it is called this because the bond between two nucleotides begin at a 3 prime end-the third carbon-. this bond then joins to a phosphate which is attached to the 5th carbon which in turn is where the 5 prime end name comes from

Question 3

Name the two bonds?

Answer 3

• Sugar phosphate bond

- Hydrogen bond

Question 4

State the 4 bases

Answer 4

• Adenine
• Thymine
• Guanine
• Cytosine

Question 5

What is a prokaryote

Answer 5

A prokaryote is a an organism which doesn’t have a nucleus. This cell most often has a single circular double stranded chromosome. Some prokaryotes also have a plasmid which is used to carry extra non-essential genes.

Question 6

What is a eukaryote

Answer 6

A eukaryote is an organism that has nucleus which containing many linear chromosomes. They also have DNA outwith the nucleus, this can be found in the mitochondria and the chloroplast.

Question 7

What is a nucleosome

Answer 7

A nucleosome is a double helix of DNA wrapped around a histone protein