2.3 Nucleic Acid

Question 1

What is a purine?

Answer 1

They are double ringed nitrogenous bases,so are bigger bases. They are A and G

Question 2

What is a pyrimidine?

Answer 2

single-ringed nitrogenous base, so they are smaller. They are C and T and U

Question 3

How are the two stands of DNA arranged?

Answer 3

They are anti parallel, so one is 3-5 and the other is 5-3

Question 4

What are the bonds between bases?

Answer 4

There is double bond between A and T and a triple bond between C and G

Question 5

Describe semi-conservative replication

Answer 5

DNA double strand separate and act as templates, producing 2 identical copies of the DNA, each has half the original strand and half the new strand

Question 6

What is the name of the covalent bond formed between the sugar and the phosphate group on the DNA backbone?

Answer 6

Phosphodiester

Question 7

What is the structure of a DNA nucleotide?

Answer 7

There is a phosphate group, a deoxyribose sugar and a nitrogenous base.

Question 8

What is the enzyme used in unwinding DNA?

Answer 8

DNA gyrase

Question 9

What is the enzyme used in unzipping DNA?

Answer 9

DNA helicase?