8.3 Flashcards
What is the definition of transcription?
The process of synthesizing RNA from a DNA template
Transcription is a crucial step in gene expression.
What is the central dogma of molecular biology?
The framework describing the flow of genetic information from DNA to RNA to protein
It outlines the processes of replication, transcription, and translation.
What are the base pairing rules for RNA?
A =U, and C = G
RNA uses uracil instead of thymine, which is found in DNA.
List the differences between DNA and RNA.
DNA is double-stranded; RNA is single-stranded
DNA contains thymine; RNA contains uracil
DNA has deoxyribose sugar; RNA has ribose sugar
These differences affect their functions and stability.
List the similarities between DNA and RNA.
Both are nucleic acids
Both are composed of nucleotides
Both play roles in genetic information storage and transfer
Despite their differences, they share fundamental characteristics.
What are the parts of a eukaryotic gene?
Promoter
Enhancer
Exons
Introns
These elements are essential for the regulation and expression of genes.
What is an enhancer?
A regulatory DNA sequence that increases the likelihood of transcription
Enhancers can be located far from the gene they regulate.
What is a promoter?
A DNA sequence that initiates transcription of a gene
Promoters are typically located upstream of the gene they control.
What are exons?
The coding regions of a gene that are expressed in the final mRNA
Exons are retained during mRNA processing.
What are introns?
Non-coding regions of a gene that are removed during mRNA processing. Going in the trash.
Introns are spliced out before translation.
What are the stages of transcription?
- Initiation
- Elongation
- Termination
Each stage plays a critical role in the transcription process.
What happens during the initiation stage of transcription?
RNA polymerase binds to the promoter region and unwinds the DNA
This stage sets the stage for RNA synthesis.
What happens during the elongation stage of transcription?
RNA polymerase synthesizes RNA by adding nucleotides complementary to the DNA template
The RNA strand grows as nucleotides are added.
What happens during the termination stage of transcription?
RNA polymerase reaches a termination signal and releases the newly synthesized RNA
This marks the end of the transcription process.
Explain what happens during the splicing process.
Introns are removed from the pre-mRNA, and exons are joined together to form mature mRNA
Splicing is essential for generating functional mRNA.
Explain what happens during alternative splicing.
Different combinations of exons are joined together, allowing a single gene to produce multiple mRNA variants
This process increases the diversity of proteins that can be encoded by a gene.
