(P) Management of Genetic Information Part 1 (module-based) Flashcards
it elucidates the intricate journey of genetic information, from its storage in DNA to its transformation into functional proteins via RNA intermediaries.
central dogma of molecular biology
The central dogma postulates that DNA holds the blueprint necessary for crafting the diverse array of____ vital to our biological processes
proteins
This genetic information is then conveyed by___, acting as a molecular courier, to the ribosomes where protein synthesis unfolds.
RNA
The conversion of DNA instructions into tangible functional products is encapsulated within the term ____.
“gene expression.”
This intricate process underpins the orchestration of cellular activities.
gene expression
Gene expression transpires through two pivotal stages
transcription and translation
a pivotal phenomenon within the realm of retroviruses, illuminates the pathway through which RNA’s genetic code is ingeniously woven into the fabric of new DNA, shaping the course of viral replication and persistence.
reverse transcription
It begins at a single origin, is bi-directional and semi-conservative.
DNA replication
T or F. DNA synthesis takes place in a direction of 3’→5’ on each parent strand.
F (5’ to 3’)
On the strand with 3’→5’ orientation, the DNA is synthesized continuously, forming a?
leading strand
The strand with 5’→3’ orientation, however, is forming a discontinuous strand called the
lagging strand
The discontinuous strand is named after its discoverer called
Okazaki fragment
Replication of DNA requires an RNA primer that is synthesized by
primase
degrades the primer and swaps it with DNA nucleotides
DNA polymerase I
The enzyme in charge for the synthesis of new DNA strands.
DNA polymerase
joins DNA ends
ligase
unravels the DNA double helix
DNA helicase
stabilizes the single-stranded regions during replication; attaches to the single strands
single-stranded DNA-binding (SSB) protein
It is needed to allow the helix to unwind which prevents extensive rotation of the chromosome
DNA topoisomerase I
separates the two daughter DNA circles following replication
DNA topoisomerase II
This polymerase is/re involved in synthesis, proof reading and repair in prokaryotes
Pol I
This polymerase is/are for repair under unique conditions in prokaryotes
Pol II, IV and V
This polymerase is/are primarily responsible for new synthesis in prokaryotes
Pol III
T or F. The direction of DNA strand synthesis is dependent on the activity of DNA polymerase.
T
DNA Pol I removes the RNA primers and replaces them with?
DNA nucleotides
crucial phase in bacterial gene expression
transcription initiation
The initiation begins with the binding of RNA polymerase to a specific region called the___, which is usually around 40–60 base pairs in length.
promoter
contain conserved elements that play a pivotal role in initiating transcription.
Promoter
In prokaryotes, two key promoter elements are recognized:
the –10 sequence (Pribnow box) , and the –35 sequence.
what is the consensus sequence of the pribnow box?
TATAAT
consensus sequences of -35
TTGACA
a critical component in transcription initiation
sigma (σ) factor
It assists in guiding the RNA polymerase to the promoter region, ensuring accurate initiation of transcription.
Sigma Factor
Unlike DNA replication, transcription initiation does not require a__. RNA polymerase directly begins synthesizing RNA using the DNA template strand.
primer
“After initiation phase, the σ subunit dissociates from RNA polymerase while the enzyme resumes RNA synthesis in a 5’→3’ direction using the four ribonucleoside 5-triphosphates as precursors. Primer is not required in this process. Specific region of the DNA double helix is unwound for transcription, forming a transcription bubble, and is then rewound following the transcription.”
Elongation
What shape is a common terminal signal formed by palindromic GC-rich region, followed by an AT-rich sequence?
hairpin shape RNA transcript
What type of RNA polymerase is present in prokaryote:
transcribes large ribosomal RNA genes
RNA pol I
What type of RNA polymerase is present in prokaryote:
transcribes protein encoding gene
RNA pol II
What type of RNA polymerase is present in prokaryote:
transcribes small RNAs (including tRNA and 5SRNA)
RNA III
T or F. Post-Transcriptional Modification takes place only in Eukaryotes.
T
T or F. Capping helps to stabilize the mRNA structure; increases resistance to cellular nucleases.
F (Addition of poly A at the 3’ end (20-250 long) )
removal of non-coding sequences (introns)
splicing
T or F. Capping is when there’s a 7-methyl guanosine triphosphate attachment at the 5’ end to protect the cleavage of the RNA by exonucleases as RNA moves out of the nucleus.
T
T or F. For translation to begin, the RNA pol must locate the promoter region first.
F (transcription)
T or F. A primer for RNA, however, is not required. But a DNA template id required.
T
T or F. As in the case of DNA replication, RNA strand also grows from 5’ → 3’ direction.”
T
