Transcription and splicing

Question 1

Brief description of how proteins are made?

Answer 1

DNA provides instruction proteins in the form of base sequences, A complimentary sequence of is made in the form of pre mRNA during transcription, pre mRNA is spliced to form mRNA, mRNA is used as a template to which complementary tRNA molecules attach and A.A. are linked to form a polypeptide chain during translation.

Question 2

Transcription is?

Answer 2

Process of making pre mRNA using DNA as a template

Question 3

Transcription 1/5

Answer 3

DNA helicase acts on a specific region of DNA causing the 2 strands to separate exposing the bases.

Question 4

Transcription 2/5

Answer 4

The nucleotide bases on the 2 template strands pair with complementary nucleotides from those present in the nucleus.

Question 5

Transcription 3/5

Answer 5

RNA polymerase joins the nucleotides together to form pre mRNA

Question 6

Transcription 4/5

Answer 6

the DNA strand rejoins behind this process as a result only about 12 bases are exposed at 1 time

Question 7

Transcription 5/5

Answer 7

RNA polymerase reaches a STOP codon and the pre mRNA detaches.

Question 8

Why must pre mRNA be spliced?

Answer 8

eukaryotic DNA contains non coding regions so splicing occurs to make the production of polypeptides smoother

Question 9

What is splicing?

Answer 9

The removal of INTRONS in the pre mRNA to ensure synthesis of polypeptides

Question 10

How and why does mRNA leave the nucleus?

Answer 10

It leaves through nuclear pores as it is so large it cannot diffuse.