Nucleic Acid

Question 1

pharmacological effects of adenosine

Answer 1

Adenosine - anti-inflammation - vasodilator - induce sleep - can induce hair growth

Question 2

Directionality of nucleic acids

Answer 2

• based on phosphodiester bond between 5th carbon and 3rd carbon of ribose

Question 3

ALWAYS read in 5’ to 3’ direction, left to
right, UNLESS stated otherwise- or both DNA and RNA
eg. ..ATGUAACUT.. = 5’-..ATGUAACUT..-3’

Question 4

Purines and pyrimidines in DNA can be methylated:

Answer 4

Bacteria - GATC sites - regulate DNA replication - DNA mismatch repair - protect against nucleases Mammalians - CG sites of promoters - regulate gene expression

Question 5

Three main types of RNA are singlestranded ribonucleic acids:

Answer 5

• Messenger RNA (mRNA): code for proteins • Ribosomal RNA (rRNA): form the core of the ribosome’s structure and catalyze protein synthesis • Transfer RNA (tRNA): adaptors between mRNA and amino acids during protein synthesis

Question 6

carry protein coding sequences • transcribed by RNA polymerase II in eukaryotes • 5’ methylguanosine cap, 3’ poly (A) tail • monocistronic message

Answer 6

mRNA

Question 7

form the large (60S) & small (40S) subunits of ribosome - 4 rRNA (28S,18S,5.8S & 5S) • function in protein synthesis

Answer 7

rRNA

Question 8

transfer amino acids for protein assembly in ribosomes - specific for each amino acid

Answer 8

tRNA

Question 9

Hairpin: single stranded nucleic acid with self-complementary sequences - eg. in tRNA loops

Answer 9

secondary structure