Nucleic Acids-Transcription and Translation

Question 1

What is mRNA?

Answer 1

Messenger RNA

Question 2

When a polypeptide is required, what is converted into a molecule of mRNA?

Answer 2

The triplet code of it’s gene.

Question 3

mRNA is like DNA in that it is a nucleic acid but what are the 4 differences?

Answer 3

-Single Stranded
-Contains Ribose
-Contains Uracil
-Easily Broken

Question 4

Transcription is the first stage of what?

Answer 4

Protein Synthesis

Question 5

What is the first stage of Transcription?

Answer 5

Helicase acts on a region of DNA to beak the hydrogen bonds between bases.

Question 6

What is the second stage of Transcription?

Answer 6

RNA polymerase moves along one of the two DNA stands (template strands)

Question 7

What is the third stage of Transcription?

Answer 7

RNA polymerase matches up complementary RNA nucleotides.

Question 8

What is the fourth stage of Transcription?

Answer 8

C matches G
G matches C
U matches A
A matches T

Question 9

What is the fifth stage of Transcription?

Answer 9

As the RNA nucleotides join together the pre-mRNA is formed.

Question 10

What is the sixth stage of Transcription?

Answer 10

The DNA behind the RNA polymerase re-joins into a double helix.

Question 11

What is the seventh stage of Transcription?

Answer 11

When the RNA polymerase reaches a ‘stop codon’ the chain is terminated and the pre-mRNA detaches.

Question 12

What is tRNA?

Answer 12

Transfer RNA

Question 13

What is the size of tRNA?

Answer 13

Small Molecule (~80 nucleotides)

Question 14

How many strands and what is the shape of tRNA?

Answer 14

Single Stranded folded into a clover leaf shape with one slightly longer section.

Question 15

What is the longer section attached to?

Answer 15

An amino acid.

Question 16

What can each tRNA carry?

Answer 16

A different amino acid.

Question 17

What are the 3 bases at the opposite end of the tRNA called?

Answer 17

Anti-codon

Question 18

What does the anti-codon pair with?

Answer 18

The complementary codon on the mRNA

Question 19

What does each amino acid have?

Answer 19

A different anti-codon

Question 20

What is the first stage of Translation?

Answer 20

mRNA attaches the ribosomes at the start codon.

Question 21

What is the second stage of Translation?

Answer 21

tRNA with a complementary anti-codon attaches to the mRNA.

Question 22

What is the third stage of Translation?

Answer 22

This tRNA is attached to an amino acid.

Question 23

What is the fourth stage of Translation?

Answer 23

The ribosomes moves along the mRNA bringing in 2 tRNA molecules at any one time.

Question 24

What is the fifth stage of Translation?

Answer 24

An enzyme and ATP are used to join the amino acids with a peptide bond.

Question 25

What is the sixth stage of Translation?

Answer 25

The first tRNA is released and can collect another amino acid.

Question 26

What is the seventh stage of Translation?

Answer 26

The process is repeated until a ‘stop codon’ is reached.

Question 27

What is the eighth stage of Translation?

Answer 27

Many ribosomes can travel along the mRNA at the same time-polysome.