T.14 TRANSCRIPTION Flashcards
(87 cards)
What does the central dogma of biology describe?
It describes the flow of genetic information: DNA is transcribed into RNA, which is translated into proteins.
What happens to non-coding RNA fragments like miRNA?
They are not translated and function to regulate gene transcription and chromatin packaging.
What determines the functions of synthesized proteins?
Posttranslational modifications determine the functions of synthesized proteins.
How are DNA sequences passed to daughter cells?
Through replication, including modifications.
Is the DNA–RNA–protein system reversible or fixed?
It is relatively reversible and highly coordinated and regulated.
What is transcription?
The process where double-stranded DNA is used to produce single-stranded RNA using one of the DNA strands.
What is a gene?
A fragment of DNA that differs from others in length and sequence.
What regions can prokaryotic genes have?
Coding and non-coding regions.
What happens in the coding region of prokaryotic genes?
It is transcribed and translated into proteins.
What is the role of the non-coding region in prokaryotic genes?
It acts as a regulatory region (e.g., promoters).
What is a polycistronic gene?
A gene with coding information for more than one protein.
What is characteristic of the promoter in eukaryotic genes?
It is longer due to more complex regulation.
What follows the promoter in eukaryotic genes?
A coding region divided into exons and introns.
What happens to the exons and introns during transcription in eukaryotes?
Both are transcribed.
What happens to introns during maturation?
They are removed; only exons are translated into proteins.
What is the function of non-coding regions in eukaryotic genes?
They serve as regulatory structures.
Are all parts of the genome transcribed during transcription?
No, only specific genes are transcribed.
How are DNA strands characterized in transcription?
They are complementary but encode different genes; only one is transcribed.
In which direction does transcription occur?
5’ to 3’, opposite to replication.
How many times is each gene transcribed?
Many times, to produce many RNA/protein copies.
What are the template and non-template strands?
Template strand is transcribed; non-template is not.
In which orientation should the template strand be written?
5’ to 3’, to reflect transcription direction.
What is TSS?
Transcription Start Site, also called +1, the nucleotide where transcription begins.
What does “downstream” mean in transcription?
Positions with positive values after +1, toward gene end.