nucleotides and nucleic acids

Question 1

what are the purine and pyrimidine bases

Answer 1

purine - adenine and guanine

pyrimidine - uracil, thymine, cytosine

Question 2

what is a nucleoside and nucleotide

Answer 2

nucleoside - sugar and base

nucleotide - nucleoside and phosphate eg cAMP (triggers utilisation of glycogen)

Question 3

describe dna structure

Answer 3

primary - sugar phosphate backbone, 5’-3’ direction
secondary - hydrogen bonds form between bases.

g and c have 3 hydrogen bonds
a and t have 2 hydrogen bonds

Question 4

what are all the forces holding dna together

Answer 4

hydrogen bonds - prevent separating
hydrophobic affects - bases inside helix
electrostatic interaction
van der waals

Question 5

describe different forms of rna

Answer 5

rRNA - combines with proteins = ribosomes - protein synthesis
mRNA - instructions for protein synthesis
tRNA - delivers amino acids to ribosome

Question 6

differences between dna and rna

Answer 6

DNA VS RNA
double vs single
bigger vs smaller
thymine vs uracil

Question 7

what is pcr

Answer 7

rapid production of dna copies
requires - target dna, 2 primers, 4 deoxyribonucleoside triphosphates, thermostable dna polymerase (taq)
it can detect infectious organisms, genetic variations