Ib Biology Transcription

What is the purpose of transcription?

• To copy DNA

• To make mRNA

• To make a protein

What is the importance of mRNA?

• It is needed to transmit information from the nucleus to the cytoplasm.

• It is needed to transmit information from the cytoplasm to the nucleus.

• Only mRNA can be 'read' by ribosomes

• mRNA is what proteins are made of

Which option best describes the first stage of transcription?

• DNA helicase breaks hydrogen bonds between the bases in DNA

• DNA helicase breaks hydrogen bonds between the bases in RNA

• DNA helicase breaks phosphodiester bonds between the bases in DNA

• DNA helicase breaks phosphodiester bonds between the bases in RNA

If the base sequence of a gene reads:

A A T C C G A T C C A C

What would the mRNA base sequence read?

• T T A G G C T A G G T G

• A A T C C G A T C C A C

• A A U C C G A U C C A C

• U U A G G C U A G G U G

What happens during the final stage of transcription?

• RNA polymerase creates phosphodiester bonds between RNA nucleotides

• DNA polymerase creates phosphodiester bonds between RNA nucleotides

• RNA polymerase creates hydrogen bonds between RNA nucleotides

• DNA polymerase creates hydrogen bonds between RNA nucleotides

In which way(s) does the structure of mRNA differ from DNA?

• mRNA has thymine whilst DNA has uracil

• mRNA is shorter than DNA

• mRNA is single stranded whereas DNA is double-stranded

• mRNA can pass through the nuclear pores whereas DNA cannot

• mRNA contains ribose whereas DNA contains deoxyribose