CH2 | The Central Dogma COPY Flashcards
The Central Dogma describes…
how genetic information flows from DNA to a protein product.
Gene expression is the process of…
genetic information flowing from DNA to RNA to protein.
The process of DNA to RNA is…
transcription.
The process of RNA to protein is…
translation.
What is it called when DNA makes more DNA?
Replication.
In the very rare cases when RNA is used to make DNA it’s called…
Reverse transcription.
Transcription copies…
a segment of DNA into RNA.
DNA segments transcribed into RNA that encode proteins are…
messenger RNA (mRNA).
DNA segments copied into RNA that do not encode proteins are…
non-coding RNAs.
mRNA comprises how much of total RNA?
1-3%.
The three steps of transcription are…
Initiation, Elongation, Termination.
The region of DNA where RNA polymerase binds to initiate transcription is the…
Promoter.
The segment of DNA that is transcribed into RNA is called the…
Coding sequence.
The region of DNA that signals the end of transcription is the…
Terminator.
In a gene, the region where RNA polymerase first binds is the…
Promoter.
The +1 site on a gene designates…
the transcription initiation site.
The region of DNA that is transcribed into an RNA molecule is the…
RNA-coding sequence.
The region of a gene that signals the end of transcription is the…
Terminator.
The DNA strand that is used as a guide to make mRNA during transcription is the…
Template strand.
The DNA strand that is not used during transcription and has a nearly identical sequence to the newly made mRNA is the…
Non-template strand.
The region towards the 5’ end of the gene relative to the coding sequence is considered…
upstream.
The region towards the 3’ end of the gene relative to the coding sequence is considered…
downstream.
During transcription, the enzyme that synthesizes RNA is…
RNA polymerase.
The DNA strand used by RNA polymerase to make mRNA is the…
template strand.
Other names for the template strand include the…
on-coding, or anti-sense strand
The newly synthesized RNA molecule is also called…
Nascent mRNA.
The DNA strand not used during transcription is called the…
non-template strand.
Other names for the non-template strand include the…
coding or sense strand.
RNA polymerase adds nucleotides to which end of the growing RNA molecule?
3’ end.
The region where RNA is temporarily bound to DNA during transcription is called the…
RNA-DNA hybrid.
During transcription, the RNA molecule is synthesized in which direction?
5’ to 3’ direction.
What is the direction of the movement of RNA polymerase along the template strand?
3’ to 5’ direction
Transcription in eukaryotes begins at which end of the gene?
3’ end (upstream) in the promoter region.
The TATA box is located how many base pairs upstream of the transcription start site?
Approximately 25-35 base pairs.
What protein binds to the TATA box?
TATA-binding protein (TBP).
TBP recruits what to the promoter?
Transcription factors and RNA polymerase II.
The complex formed at the promoter that initiates transcription is called the…
transcription initiation complex.
Why is the TATA box a common site for DNA unwinding?
Because it is rich in A and T bases, which have fewer hydrogen bonds than G and C, making them easier to separate.
In eukaryotes, the main RNA polymerase enzyme that is involved in transcribing most genes is…
RNA polymerase II
In a eukaryotic promoter, what’s the start point?
Where the actual transcription of the gene begins, designated as +1 on the DNA sequence.
After the transcription initiation complex forms then…
RNA synthesis begins.
During elongation, the template DNA strand is read in which direction?
3’ to 5’ direction.
RNA synthesis during elongation occurs in which direction?
5’ to 3’ direction.
The DNA strand that has a sequence nearly identical to the new mRNA (except for T’s replaced with U’s) is the…
coding strand.
What enzyme catalyzes the formation of phosphodiester bonds between adjacent ribonucleotides in the growing RNA molecule?
RNA polymerase.
What are the differences between the sequences in the mRNA and coding strand?
The base sequences are identical except T in DNA is replaced by U in RNA.
The region of DNA that signals the end of transcription is the…
terminator.
During termination, what happens when RNA polymerase recognizes the termination sequence?
It changes conformation, releasing itself from the template strand, and stops transcription.
What happens to the DNA template during termination?
It rewinds back into a double helix.
The RNA molecule released at the end of transcription is called…
Pre-mRNA.
During transcription, which DNA strand is read to synthesize RNA?
The template strand.
What is the corresponding RNA base for Adenine (A) in DNA during transcription?
Uracil (U).
What is the corresponding RNA base for Thymine (T) in DNA?
Adenine (A).
What is the corresponding RNA base for Cytosine (C) in DNA?
Guanine (G).
What is the corresponding RNA base for Guanine (G) in DNA?
Cytosine (C).
In what direction is the template DNA strand read?
3’ to 5’ direction.
In what direction is the RNA molecule synthesized?
5’ to 3’ direction.
Where is pre-mRNA produced?
In the nucleus.
Pre-mRNA is transcribed from what type of chromosome?
Linear.
What three processing steps must pre-mRNA undergo to become mature mRNA?
5’ capping, poly-A tail addition, and splicing.
The addition of a methylated guanine to the 5’ end of pre-mRNA is called…
5’ capping.
The addition of a string of adenine nucleotides to the 3’ end of pre-mRNA is called…
poly-A tail addition.