Translation

Question 1

What does mRNA nucleotide sequence do?

Answer 1

Used to synthesis proteins from the start codon (AUG/Methianine)

Question 2

What are the three stop codons?

Answer 2

UAA
UAG
UGA

Question 3

Codons do not directly bind to amino acids, what adaptor molecule is used to convert codons into amino acids?

Answer 3

tRNA

Question 4

What is the peptidyl tRNA attached to?

Answer 4

Attached to the C terminus of the growing polypeptide however lets go and another tRNA molecule attaches an amino acid to the polypeptide chain

Question 5

Where is protein synthesis performed?

Answer 5

At the ribosomes

Question 6

What are ribosomes made of?

Answer 6

Made from proteins and ribosomal RNAs

Question 7

Prokaryotic RNA which is 70s subunits made up of?

Answer 7

Large top subunit which is 50s
Small top subunit which is 30s (16srrna)

Question 8

What are the ribosome binding sites and what are they binding sites for?

Answer 8

E site (exit)
P site (peptidyl tRNA)
A site (aminoacyl tRNA)

Binding sites for mRNA (small subunit area) and tRNA

Question 9

How is amino acid selected?

Answer 9

Complementary base pairing using anticodon tRNA and codon on mRNA

Question 10

What are the three stages of translation?

Answer 10

-Initiation
-Elongation
-Termination

Question 11

Explain first step of initiation in Eukaryotes

Answer 11

Initiator tRNA binds AUG at P site of ribosome (usually tRNA moves into A site first but this is an exception).

Question 12

Explain first step of initiation in prokaryotes

Answer 12

Small ribosomal subunit aligns ribosome on mRNA -Shine-Dalgarno sequence in rRNA base pairs to sequence in mRNA

Question 13

Once AUG codon is in place site of the small ribosomal sub unit, what happens?

Answer 13

Binding of large ribosomal subunit occurs leading to next step which is elongation