RNA biochemistry and molecular biology

Question 1

what are the 2 classes of RNA?

Answer 1

informational and functional

Question 2

describe mRNA and list what RNA class it is;

Answer 2

copied from protein coding-genes; it is the short lived intermediary between DNA and protein. It is the only type of RNA that undergoes translation. Messenger for protein production

informational

Question 3

what are functional RNAs?

Answer 3

do not encode proteins instead the RNAs themselves perform functional roles in the cell

Question 4

what are transfer RNAs?

Answer 4

encoded in dozens of forms and are covalently joined with an amino acid, which they bring into the ribosome for inclusion into a growing protein chain. Translation of RNA codon to amino acid

Question 5

what are ribosomal RNAs?

Answer 5

folds and assembles along with numerous proteins to form ribosomes

Question 6

what are small nuclear RNAs?

Answer 6

found in the nucleus of eukaryotes and plays a role in mRNA splicing

Question 7

what are micro and small interfering RNAs?

Answer 7

active in plant and animal cells and are involved in posttranscriptional regulation of mRNA

Question 8

what is CRISPER RNA?

Answer 8

found in bacterial cells and plays a role in defending the host from attack by bacteriophage

Question 9

what are ribozymes?

Answer 9

: certain RNAs in eukaryotic cells have catalytic activity

Question 10

what is the structure of RNA?

Answer 10

ribonucleotides joined by phosphodiester bonds
(base, sugar and phosphate)

Question 11

why do RNA polynucleotides fold?

Answer 11

due to internal hydrogen bond formation and base-pairing

Question 12

what are the characteristics of chemical modified RNA?

Answer 12

Chemical modifications are usually permanent but not regulatory and conserved among species

Question 13

what are the 2 most prominent modifications of tRNA?

Answer 13

dihydrouridine and pseudouridine

Question 14

what happens if adenine is not modified at position 37?

Answer 14

encephalopathy and myoclonic epilepsy

Question 15

how can RNA fold to form double helicies?

Answer 15

if 2 stretches of RNA nucleotides are perfectly complementary - tend to be short

Question 16

do RNA base pairs follow watson crick rules?

Answer 16

no

Question 17

what is primary structure of RNA?

Answer 17

RNA sequence 5’ to 3’

Question 18

what is secondary structure of RNA?

Answer 18

short double helical regions

Question 19

what is tertiary structure of RNA?

Answer 19

arrangement of the double-helices and single-stranded regions in the final configuration of RNA. form when 2 different parts of an RNA molecule interact with one another

Question 20

what is a hairpin?

Answer 20

if complementary sequences are close to one another

Question 21

wh\t is coaxial stacking?

Answer 21

occurs when the end base-pair in one double helix interacts with the end base pair in a different double helix
Form A-type helices

Question 22

what makes RNA unstable?

Answer 22

ribose

Question 23

what is the reaction through which hydrolysis takes place?

Answer 23

SN2 displacement reaction

Question 24

what is the result of hydrolysis?

Answer 24

an equimolar mixture of 2’ and 2’ NMPs

Question 25

how do you ensure the preservation of RNA?

Answer 25

never let the pH of an RNA solution become alkaline and never touch RNA with bare hands

Question 26

what is good aout the 2’ OH in ribose?

Answer 26

permits RNA to form hydrogen bonds more prolifically than DNA allowing more inter and intramolecular interactions