Mutations
Below are two sequences of a segment of DNA.
Normal sequence: TTA AAA GGA
Mutated sequence: CTT AAA AGG A
Which type of mutation has occurred?
Insertion Mutation
The following DNA strand is used as a template for transcription: 3' CGTAAGCGGCT 5'
Which of the following RNA strands will be produced?
5' GCAUUCGCCGA 3'
Given the RNA: 5' UCU UGU CGA 3'
What is the amino acid sequence?
Ser - Cys - Arg
Below are two sequences of a segment of DNA.
Normal sequence: TAA GCG CAT
Mutated sequence: TAG CGC AT
Which type of mutation has occurred?
Deletion Mutation
What is an open state of chromatin where all nearby genes are transcriptionally active?
euchromatin
Below are two sequences of a segment of DNA.
Normal Sequence: GGG ACG TTG
Mutated Sequence: GGG ACC TTG
Which type of mutation has occurred?
Substitution mutation
The following DNA strand is used as a template for transcription:
3' CGTAAGCGGCT 5'
Which of the following RNA strands will be produced?
5' GCAUUCGCCGA 3'
A template strand of DNA in a gene reads:
3' TCT CCA AGC 5'
Arg - Gly- Ser
A template strand of DNA is 3'GATCCAAAATGT 5'
What is the complementary DNA strand that is created from this template during replication?
5' CTAGGTTTTACA 3'
What is heterchromatin?
A closed state in which most or all nearby genes are transcriptionally inactive
A deletion mutation occurs, leaving 14 nucleotides in a DNA sequence.
What is the maximum number of amino acids that could be coded for by this sequence?
4
The following RNA strand was produced:
5' AUG GCG UUU 3'
Which of the following DNA strands could have been the template for this RNA?
3' TAC CGC AAA 5'
A template strand of DNA in a gene reads: 3' CTC CGC TTT TAG 5'
Using the codon chart, what is the sequence of amino acids that is produced after translation?
Glu - Ala - Lys - Ile
The product of the lacI gene regulating the lac operon is most like a car's ________.
Parking brake
As cells progress from embryonic cells to terminally differentiated cells, chromatin tends to become more....
heterochromatic (methylated DNA, deacetylated histones)
What type of mutation does not result in change of the AA sequence?
Silent mutation
The following RNA strand was produced:
5' AAA AUG AGU AAG 3'
Which of the following DNA strands could have been the template for this RNA?
3' TTT TAC TCA TTC 5'
What is the anti-codon of the tRNA for Asp?
(two possible answers)
3'-CUA-5' or 3'-CUG-5'
It has been estimated there are approximately 20,000 gene in the human genome that code for protein. Yet estimates of the total number of proteins range from 50,000-100,000in the human proteome. How can we account for this discrepancy?
Alternative RNA splicing
How do chromatin-remodeling complexes recognize the genes they should act on?
Chromatin-remodeling complexes recognize specific transcription factors bound to regulatory sequences of DNA
Which class of DNA mutation results in the substitution of one amino acid for another in the protein product?
Missense mutations
If you were to create a drug that recognized and bound irreversibly to the promoter region of a specific gene, thereby blocking it, what effect would you expect that drug to have?
Both transcription and, eventually, translation of the gene would halt
Consider the anticodon 3'-UGG-5' on a t-RNA.
What is the DNA sequence for the codon?
5'-GGT-3'
A miRNA that is a perfect match for an mRNA leads to ____, whereas miRNA that is partially complementary leads to _____
mRNA degradation, mRNA silencing (inhibits splicing or translation)
If you wanted to transform heterochromatin to euchromatin, you could add which of the following enzymes.
- histone acetyl transferase (HAT) to acetylate the heterochromatin
- DNA demethylase to de-methylate the heterochromatin