Nucleic Acids Flashcards
1
Q
Descirbe the structure of RNAs nucelic acids
A
Single stranded Shorter Ribose rather than deoxyribose DNA-> ribosomes Uracil instead of tymine
2
Q
What are ribosomes made of?
A
rRNA and protein
3
Q
What are the complementary base pairs in DNA?
A
Adenine thymine
Guarnine cytosine
4
Q
Why would a DNA molecule with more cytosine and guarnine be more stable?
A
Form three hydrogen bonds per pair as opposed to 2 for A-T
5
Q
Describe semi conservative replication
A
DNA helicase breaks hydrogen bonds between base pairs
Double helix unwinds and separates into two strands
Free nucleotides that are complementary will bind to base pair
DNA polymerase builds up the phosphodiester backbone by formin phosphodiesterbonds between phosphate and ribose
6
Q
Describe the evidence for semi conservative replication
A
Sample grown in N14 Another grown in N15 For one cycle N14 sample replicates in N15 The three samples are centrifuged N15 sample is heavier so is lower N14 sample is lighter so higher N14/N15 sample in middle
