dna & protein synthesis

Question 1

what is the structure of a MRNA

and its function

Answer 1

-single stranded
-long
function:
-acts as a template for translation

Question 2

what is the structure of a TRNA.

and its function

Answer 2

• single stranded
• but folded into a clover leaf like structure
• has amino acid attached
• has anticodons
  function:
• amino acids is a binding site
  -Brings amino acids together

Question 3

what is produced in transcription

Answer 3

MRNA

Question 4

where does transcription take place.

Answer 4

in the nucleus

Question 5

in points explain transcription

Answer 5

• in nucleus
• DNA unwinds by DNA helicase
• DNA strands are exposed
• free floating nucleotides join to complementary bases in template strand (forms temporary hydrogen bond).
• RNA polymerase binds the RNA and DNA together
• phosphodiester bond is formed
• RNA and DNA keep binding until stop codon is reached.
• MRNA detaches DNA strand and leaves the nucleus via nuclear pores.

Question 6

how do you turn PRE-MRNA to MRNA

and what does this process do

Answer 6

splicing

- this is when the introns are removes from the strand

Question 7

what does translation produce

Answer 7

polypeptides ( proteins)

Question 8

where does translation take place

Answer 8

ribosomes

Question 9

in points explain translation

Answer 9

• TRNA anticodons bind to MRNA codons forms hydrogen bonds
• two amino acids join together during condensation reaction to form peptide bonds.
• the TRNA detaches itself
• the ribosomes moves along the MRNA until stop codon is reached.

Question 10

what is the role of ribosomes

Answer 10

• where translation takes place

- allows peptide bonds to form between amino acids*

Question 11

what is the role of TRNA

Answer 11

allows amino acids to join to each other

Question 12

what is the role of ATP

Answer 12

• releases energy

- for the formation of a peptide bond between two amino acids.