MIDTERM | Transcription, Translation, And Mutation Flashcards
the process of synthesizing mRNA from genomic DNA
Transcription
the process in which information encoded in the DNA molecule is copied into an mRNA molecule
Transcription
DNA-dependent RNA polymerase
Enzyme
is the basic unit of heredity. It is a part of the DNA that is involved in the synthesis of proteins including its regulation.
Gene
the portion of the DNA which controls gene expression
Regulatory Gene
the portion of the DNA which is transcribes into mRNA
Structural Gene
RNA is initially synthesized using a DNA template in the process called ____
Transcription
____ is initially synthesized using a DNA template in the process called transcription
RNA
All four ribonucleoside triphosphates
ATP, GTP, CTP, and UTP
True or False?
A primer is not needed in RNA synthesis, but a DNA template is required.
True
Parts of Transcription
- Initiation
- Elongation
- Termination
scans the DNA molecule and binds at the promoter region
TATA binding proteins
binds to the promoter region and other Transcription Factors are recruited
RNA polymerase
Transcription will start upon clearance by
transcription factors and enhancer molecules
binds to promoter region recruiting the
RNA polymerase in the close promoter complex.
Sigma factor
In RNA Splicing, expressed DNA sequences are called
exons
In RNA Splicing, intervening DNA sequences that are not expressed are called
introns
The synthesis of polypeptides using the mRNA transcript as the template.
Translation
is composed of 3 bases in the mRNA which encode an amino acid
Codon
is composed of 3 bases in the tRNA which is complementary to the codon
Anti-Codon
A codon relates the genetic information to an amino which can be deciphered using the ________
Genetic Code
KEY FEATURES OF THE GENETIC CODE
- Triplet
- Nonoverlapping
- Commaless
- Degenerate
- Universal
Parts of Elongation
- aa-tRNA binding
- Peptide bond formation
- Translocation
Initiated by termination sequences __________
UAG, UGA, UAA
Release factors binds to the A site initiating the release of the newly synthesized polypeptide and disassembly of the ribosome complex
Termination
Covalent modifications or introduction of organic moieties to the polypeptide
POST-TRANSLATIONAL MODIFICATION
In ______ , initiation factors, ribosomes (30S and 50S) and f-met tRNA bind to the mRNA.
chain initiation
Steps in Translation
Amino acid activation => Chain initiation => Chain elongation (repeated many times) => Chain termination
tRNA is charged with the amino acid at the 3’ end
Amino acid activation
This tail protects the mRNA from nucleases and phosphatases
A polyadenylate “tail”
A polyadenylate “tail” that is usually ______ nucleotides long, is added to the 3’ end before the mRNA leaves the nucleus.
100-200
is made up of snRNAs
Spliceosome
are separated by intervening intron
Exons
True or False?
Eukaryote genes frequently contain intervening base sequences that appear in the final mRNA of that gene product.
False. “ do not appear in the final…”
Function of 5’cap:
• Prevents 5’ end from being digested
• Aids in the transport of mRNA out of the nucleus
• Plays a role in the initiation of mRNA translation
is any event where there is a change in the sequence of the bases of the DNA molecule
Mutation
Usually a heritable phenomenon which happen during DNA replication
Mutation
single nucleotide changes
Point mutation
Types of Mutation
1) Point Mutation
2) Frameshift Mutation
addition or removal of two or more bases in the DNA.
Frameshift Mutation
Two types of point mutation
Transition and Transversion
Two types of Frameshift mutation
Insertion and Deletion
purine to purine substitution/ pyrimidine to pyrimidine
Transition
purine to pyrimidine/ pyrimidine to purine
Transversion
addition of bases in the DNA causing a shift in the reading frame
Insertion
removal of bases in the DNA causing a shift in the reading frame
Deletion
Types of Mutagens
1) Physical mutagens
2) Chemical agents
Types of Mutations (At the DNA Level)
1) Substitution
2) Deletions
3) Insertion
4) Inversions
“ionizing radiation”
what types of mutagens?
Physical Mutagen
“UV light”
What type of mutagens?
Physical mutagens
