Genetics Exam 3 Review Flashcards
T or F Oligonucleotides require restriction sites?
False
Which chemical’s mutations cannot be reversed?
Hydroxylamine
What causes DNA damage resulting in thymine dimers?
UV light
Which of the following is an example of a transversion and not a transition mutation?
A > C or T
Purine replaced by a pyrimidine or vice versa
Which of the following disorders is not caused by expanding trinucleotide repeats?
Down syndrome
These are mobile DNA sequences that allow genes to translocate from one loci to another
Transposable elements
What disease is caused by a deletion in chromosome 15?
Prader-willi syndrome
What is the unit of measurement in physical maps?
Base pairs
What type of mutations must occur to get the following chromosome sequence from the original?
One was a duplication and translocation and the other one was just duplication
T or F Allopolyploidy arises from hybridization between two species; the resulting polyploid carries chromosome sets derived from two or more species?
True
T or F Turner syndrome, down syndrome and Klienfelter syndrome are caused by aneuploidy?
True
Aneuploidy refers to variations in chromosome numbers
T or F Adjacent-1 and adjacent-2 segregation occur at the same frequency
False
Adjacent-1 is more common and adjacent-2 is rarer because the two homologous chromosomes usually separate in meiosis
T or F During replicative transposition, transposable elements are exchanged between homologous chromosomes
False
Does not have to be homologous chromosomes
In an individual, chromosomes can form an inversion loop during pairing in prophase I. With one crossing over, a structure, a dicentric bridge, forms where one chromatid has two centromeres and one lacks a centromere. What chromosomal rearrangement is this present in?
Paracentric inversions
Non-reciprocal translocations demonstrate which type of mechanism?
Cut and Paste
What type of mutation alters the amino acid sequence but does not change the function of the protein?
Neutral mutation (Silent mutations are mutations within the codon that gives the same amino acid in the end, does not result in altered amino acid sequence or function)
T or F Hydroxyamine causes mutations that are not reversible
True
What type of DNA repair mechanism does not repair pyrimidine dimers?
Mismatch repair
Before replicative transposition a single copy of the transposable element is found on only one DNA molecule. During replicative transposition two DNA molecules are joined together into a fused A+B molecule with two copies of the transposable element. This is called?
Cointegrate
Which DNA sequences are used in DNA fingerprinting?
Microsatellites
Which of the following theories have been proposed about transposable elements?
All of the above
- Transposable elements are genomic parasites
- Transposable elements produce mutations that lead to genetic variation
- Transposable elements have their tendencies replace by properties useful to the cell
What technique is used to transfer RNA?
Northern blotting Mnemonic = SNOW/DROP Southern - DNA Northern - RNA Western - Protein
T or F oligonucleotide directed mutagenesis is used when appropriate restriction sites are available
False
Knockout mice have a normal gene disabled by insertion of this gene into the target gene sequence
Neo+
T or F DNA transposons are the only transposons present in eukaryotes
False, retrotransposons are present too
What is the gestation period of a mouse?
21 days
An individual with down syndrome has trisomy 21, how many chromsomes is present in each cell?
47
Supercoiling in DNA is relieved by?
Enzyme that adds or subtracts coils
Topoisomerases
What is histone is not a component of a nucleosome?
H1, linker histone that holds linker DNA
The movement of genetic material between non-homologous chromosomes
Translocation
T or F Only DNA transposons are found in eukaryotes
False
Artificial chromosomes do not need?
Selectable markers
Not a result of trinucleotide repeats
Trisomy 21
An intragenic suppressor mutation may act by
Change a second nucleotide in the same codon altered by the original mutation, producing a codon that specifies the same amino acid as that specified by the original, unmutated codon
Not sure what the question is…
Duplication
