molecular biology<3

Question 1

what are eukaryotes Mrna structural feactures

Answer 1

semi loop - involved in regulating efficiency of translation

Question 2

define ribosomes

Answer 2

large riboneucleoproteins that synthesis polypeptides

Question 3

overview of translation

Answer 3

Mina acts as template for amino acid chain
3 bases on RNA= one amino acid
Mrna reads on ribosome
Trina brings amino acids to ribosome and join to previous

Question 4

one amino acid is coded from by

Answer 4

triplet of bases

Question 5

how many stop codons

Answer 5

3

Question 6

what is the wobble hypothesis

Answer 6

first two bp have most specify, 3rd is less stringent

Question 7

three stages of translation are

Answer 7

initiation
elongation
termination

Question 8

initiation and elongation require what

Answer 8

energy GTP

Question 9

translation what is the start codon?

Answer 9

AUG (methionie)

Question 10

termination what are the stop codons

Answer 10

UAA
UGA
UAG

Question 11

translation takes place where

Answer 11

ribosome in cytoplasm

Question 12

what is transfer RNA

Answer 12

small pieces of DNA with a 3D structure (clover leaf)

Question 13

one end of transfer DNA has —— —– attached and other has ———–

Answer 13

amino acid

anticodon

Question 14

how many ribosomes can work on same polypeptide?

Answer 14

several

Question 15

what does several ribosomes working on same stretch of DNA do?

Answer 15

enables several proteins to be made at once

Question 16

amino acid residues attach to each other with

Answer 16

peptide bond

Question 17

what do release factors do?

Answer 17

recognise stop codon abd modify ribosome to activate ribosymes which sever polypeptide from final TRNA

Question 18

what happens if DNA sequence changes

Answer 18

alternative MRNA made and therefore, alternative amino acid sequence

Question 19

name types of mutations

Answer 19

point

frameshift

Question 20

point mutation is when

Answer 20

one or a few base pairs are effected

substitutions, insetrions, deletions

Question 21

frameshift mutation is when

Answer 21

neucleotide triplets after mutation displaced

insertions/deletions

Question 22

what is substitutions

Answer 22

1 base pair replaced

Question 23

what is nonsence codon

Answer 23

codon changed to termination codon
polypeptide too short
inactive protein produced

Question 24

what is a silent mutation

Answer 24

base changed but amino acid is the same