ribose adenine uracil adenine single

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RNA and Transcription

ribose

What is the sugar found in RNA?

Adenine Uracil

What base is present in DNA but is missing in RNA? What base replaces it?

Adenine

Uracil in RNA pairs with ____ in DNA.

Single

Is RNA single or double stranded?

mRNA – single stranded chain; takes message from DNA to ribosomes

rRNA – globular with proteins; makes up ribosomes

tRNA – hairpin or cloverleaf; transfers aa to ribosomes

What are the three types of RNA? What are their shapes and functions?

mRNA

Which type of RNA copies DNA’s instructions for making proteins in the nucleus?

rRNA

Which type of RNA is most abundant?

rRNA and proteins

What two things make up ribosomes?

Copying genetic info from DNA into RNA

What is transcription?

Initiation Elongation Termination

What are the three steps of transcription?

Ribosomes

Where are proteins made?

Primary transcription enzyme Adds complimentary RNA bases to DNA

template to build RNA transcripts

What is RNA polymerase? What does it do?

Promoter Coding sequence Termination signal

What are the three parts of a gene?

Promoter – initiation Coding region – elongation Termination signal – termination

Each part of a gene corresponds to one step of transcription. Which part of a gene corresponds to which step?

Marks the beginning of a gene Where RNA pol binds to start tscn

What is a promoter?

The promoter

Where does RNA pol bind to the DNA it’s transcribing?

It opens Transcription bubble or puff

What happens to the DNA when RNA pol binds? What is this open region called?

no

Are both strands of DNA copied during transcription?

RNA pol adds RNA nt to build transcripts

What happens during elogation?

template

What is the name of the strand that is read?

5’ to 3’

Which direction does RNA pol work?

3’ to 5’

Which direction does it read?

3’ to 5’

So the template strand runs ____ in the direction the RNA pol moves.

Coding strand

What is the name of the DNA strand that is being made into an RNA copy?

Marks the end of the DNA that’s being transcribed

What is a termination signal?

transcripts

What are the products of transcription?

All 3 kinds!

What kinds of RNA are made during transcription?

Pre-mRNA

What is the direct result of transcription of protein-coding genes in eukaryotes?

Processing! ◦ Capping◦ Splicing

What must happen to pre-mRNA before it leaves the nucleus?

splicing

What do we call the process in which intervening sequences are removed from pre-mRNA and remaining sequences are “glued” together?

Introns Introns intervene or interfere

What do we call the intervening sequences?

Exons Exons are expressed

What do we call the remaining sequences that are “glued” together?

Into the cytoplasm to the ribosomes for translation

Once the processed mRNA leaves the nucleus, where does it go?

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