8-4 TRANSCRIPTION
A gene is a set of _________________________________that control the synthesis of proteins within the cell. This
process, called protein synthesis, involves 2 steps: ________________________ and ___________________________
_____________ carries DNA’s instructions.
The central dogma states that information flows in one direction _____________ to
__________________ to ________________ and involves three processes:
1.______________________________
2______________________________
3______________________________
DNA cannot leave the _________________________, so a copy is made in the form of a similar nucleic acid called
_______________(ribonucleic acid) during _____________________________.
After DNA is used to make RNA, the RNA is then used to make ___________________ during _________________by
ribosomes in the ___________________________.
How is DNA different from RNA?
RNA contains the sugar ___________________and DNA contains the sugar ____________________
RNA is ________________________, DNA is _____________________________
RNA contains ________________instead of ____________________. Uracil, like thymine, is a
pyrimidine (contains one ring).
RNA and DNA are both a __________________________________ macromolecule.
RNA is made of nucleotides.
Both DNA and RNA have ________________________, ______________________, and
_________________
Three types of RNA
1.messenger RNA (mRNA):
__________________________________________________________________________
This type of RNA acts as a “messenger” bringing the information in the DNA to the ribosome.
2.ribosomal RNA (rRNA): _________________________________
( Recall that ribosomes synthesize proteins.) Ribosomes are made of both proteins and rRNA.
3. transfer RNA (tRNA):
Brings amino acids to the ribosome to be added to the polypeptide chain that is being made at the
ribosome. There is one tRNA for each of the 20 amino acids.
Transcription (In the _________________)
Transcription is the process in which the nucleotide sequence of _______________ is copied, within the nucleus, into a
_______________________________nucleotide sequence of RNA. DNA  mRNA
Transcription
Step 1:
The enzyme _____________________________________ binds to the DNA and separates the 2 DNA strands.
Step 2:
RNA polymerase uses only one strand of DNA as a template to make a ___________________________ RNA strand.
RNA Polymerase reads _______________  ______________________
DNA is like the “master plan” and mRNA is like the “blueprint.”
The master plan stays in the office (the nucleus) and the blueprint can be taken to the construction site (the ribosome).
Step 3
Once RNA is made, the RNA detaches from the template strand, leaves the nucleus through ____________________,
and enters the _____________________ of the cell and go to a ____________________________
Cells have the ability to control what genes are expressed and how often they need to be transcribed.
Cells will cut out pieces from the mRNA that they do not wish to use or add promoters before a particular gene so it is
transcribed more often.
Practice with Transcription
If this is the given DNA strand: Write out the complementary mRNA strand made during transcription
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