2.1.3 Nucleotides and nucleic acids

Question 1

what are the 3 components of a nucleotide

Answer 1

a pentose sugar
a nitrogenous base
a phosphate group

Question 2

what is the diffence, in structure, between RNA and DNA

Answer 2

DNA has a deoxyribose sugar but RNA has a ribose sugar
in RNA the base thymine is replaced by uracil
DNA is double-stranded (double helix) but RNA is single-stranded

Question 3

describe the difference between a purine and a pyrimidine

Answer 3

purine=double ring structure
pyrimidine=single ring structure

Question 4

name the purine bases

Answer 4

adenine and guanine

Question 5

name the pyrimidine bases

Answer 5

cytosine, thymine and uracil

Question 7

how does deoxyribose differ to ribose

Answer 7

deoxyribose contains one fewer oxygen atom than ribose

Question 8

how are nucleotides joined together

Answer 8

condensation reaction

Question 9

what the linkage called between two nucleotides

Answer 9

phosphodiester bond

Question 10

what is the chain of alternating phosphate groups and pentose sugars in DNA or RNA called

Answer 10

sugar-phosphate backbone

Question 11

describe the strcuture of ATP

Answer 11

phosphorylated nucleotides, comprised of 3 phosphate groups, adenine and ribose sugar