Topic 3 (transcription)

Question 1

What does transcription make?

Answer 1

Convert DNA to mRNA

Question 2

In which strand of DNA does transcription occur?

Answer 2

Only in one strand of DNA, in the antisense strand (3’ to 5’)

Question 3

What is the most important enzyme in this transcription?

Answer 3

RNA polymerase

Question 4

Explain the first stem of transcription

Answer 4

Initation, RNA polymerase is attached to a specific region of DNA, called promotor. The promotor has a specific sequence which is called the signal sequence. Then the RNA polymerase unwinds the two strands of DNA.

Question 5

Explain the second step of transcription.

Answer 5

Elongation, the RNA polymerase starts to add nucleotides using the DNA as template, the nucleotides are complementary to the strand. Then, the RNA molecule is synthesized.

Question 6

Which direction does RNA polymerase read the DNA strand in transcription.

Answer 6

3’ to 5’ (template or antisense way)

Question 7

Which direction is the RNA elongated in transcription?

Answer 7

5’ to 3’ (coding or sense strand way)

Question 8

Explain the third step of transcription

Answer 8

Termination, transcription finishes when a termination sequence reaches the RNA polymerase. Then, RNA polymerase detaches from the DNA and the newly formed mRNA leaves from the DNA.

Question 9

State the three steps of transcription

Answer 9

Initiation, elongation and termination.

Question 10

Explain the results of transcription

Answer 10

An RNA molecule, with a different complementary sequence than the template strand.

Question 11

Explain what strand does transcription copy.

Answer 11

The goal of transcription is to copy the template strand, to do so, it attaches to the antisense strand to attach the the complementary bases substituting thymine for uracil. In that way, transcription will have replicated the template strand by creating a new one by attaching the complementary bases to the antisense strand.