2.1 structure of nucleic acids

Question 1

what 3 components are in a nucleotide?

Answer 1

• pentose sugar
• phosphate group
• nitrogenous base

Question 2

what are the 5 nitrogenous bases?

Answer 2

adenine, guanine, thymine, cytosine, uracil

Question 3

which base is only exclusive in DNA?

Answer 3

thymine

Question 4

which base is only exclusive in RNA?

Answer 4

uracil

Question 5

where does a phosphodiester bond form?

Answer 5

between a 5’ phosphate & a 3’ sugar

Question 6

what type of backbone does a nucleotide form?

Answer 6

sugar-phosphate backbone

Question 7

in which direction are polynucleotides read?

Answer 7

5’ to 3’

Question 8

full name of RNA

Answer 8

ribonucleic acid

Question 9

which bases are in RNA?

Answer 9

A, U, G, C

Question 10

list the 3 types of RNA.

Answer 10

• mRNA
• tRNA
• ribosome RNA

Question 11

full name of DNA

Answer 11

deoxyribonucleic acid

Question 12

which, DNA or RNA has a double-stranded structure? is it longer or shorter than the other?

Answer 12

DNA, longer

Question 13

name the pentose sugar in RNA.

Answer 13

ribose

Question 14

name the pentose sugar in DNA.

Answer 14

deoxyribose

Question 15

how do bases pair by?

Answer 15

complementary base pairing

Question 16

which base pair is double bonded?

Answer 16

A = T

Question 17

which base pair is triple bonded?

Answer 17

G - C

Question 18

explain how the stability of DNA is a structural advantage.

Answer 18

• reactive bases protected by sugar-phosphate backbone -> avoids mutation & corruption of information
• more stable with more G-C bonds
• interactive forces act vertically due to base stacking

Question 19

why are there 2 polynucleotide strands in DNA?

Answer 19

for replication & transcription

Question 20

how could DNA carry information?

Answer 20

• infinite variety of sequences since DNA is extremely long
• passes genetic information to cells & generations
• hereditary (inheritance) material -> genetic diversity & speciation