DNA Recombination, Mutagenesis, Repair

Question 0

Another term for RNA-dependent DNA polymerase

Answer 0

Reverse Transcriptase

Question 1

Mixing and matching of genes, producing genetic variability

Answer 1

Genetic Recombination

Question 2

Unites two DNA molecules that have crossed over

Answer 2

Heteroduplex joint

Question 3

Cross-strand exchange involving 4 DNA strands shared by 2 helices, where two of the strands are switched

Answer 3

Holliday Junction

Question 4

Localized changes that can lead to loss or gain of functional phenotypes

Answer 4

Mutations

Question 5

TRUE/FALSE: loss of function mutations indicate dominant inheritance.

Answer 5

FALSE. Loss of function indicate recessive alleles whereas gain of function mutations indicate the presence of a dominant allele.

Question 6

Translocation wherein two acentric nonhomologous chromosomes cross over

Answer 6

Reciprocal

Question 7

Translocation where fragment includes centromere

Answer 7

Pericentric

Question 8

Unequal genes are present due to mismatch correction; prevented by mismatch proofreading

Answer 8

Gene conversion

Question 9

A gene or a region of a chromosome is replicated many times over, sometimes yielding pseudochromosomes

Answer 9

Gene amplification

Question 10

Genetic change involving the loss or gain of entire chromosomes

Answer 10

Aneuploidy; eg. Down Syndrome – trisomy 21 that may be caused by a deletion in another chromosome

Question 11

Processed genes altered so they contain nonsense codons, unable to produce functional proteins

Answer 11

Pseudogenes

Question 12

Leads to microsatellite changes and trinucleotide repeat expansion diseases

Answer 12

Replication slippage

Question 13

Pyrimidine-pyrimidine substitutions

Answer 13

Transition

Question 14

Purine-pyrimidine substitutions

Answer 14

Transversion

Question 15

Correction of wrong nucleotide by reversal of DNA damage

Answer 15

Direct repair

Question 16

Base is removed by glycosidase and replaced

Answer 16

Base excision repair

Question 17

Stretch of DNA around the site of damage is removed and replaced

Answer 17

Nucleotide excision repair

Question 18

Binds to p53 which is activated upon irreparable DNA damage

Answer 18

MDM2

Question 19

DNA polymerase proofreading machinery

Answer 19

5’-3’ exonuclease activity