Bio 283 Exam 3

Select the statements that explain why duplication is a driving force for evolution and the generation of new genes. a) Duplicated genes provide extra copies of DNA that are not constrained by an essential function b) duplication of a chromosomal region always results in novel phenotypes c) phenotypic variations can occur when random fixed mutations are introduced into a new chromosome d) genes duplicate and then diverge from the original sequence to create multigene families

a) Duplicated genes provide extra copies of DNA that are not constrained by an essential function c) phenotypic variations can occur when random fixed mutations are introduced into a new chromosome d) genes duplicate and then diverge from the original sequence to create multigene families

_______ is a type of polyploidy that arises from the hybridization between two different species a) allopolyploidy b) paracentric inversion c) tetrasomy d) autopolyploidy

a) allopolyploidy

two brothers have x-linked red-green colorblind vision, and their parents have normal color vision. The first brother's karyotype is 47, XXY and the second brother's karyotype is 46, XY In which parent and in what cell division phase did the first brother's chromosomal nondisjunction occur? a) in the mother in meiosis II b) in the mother in meiosis I c) in the father in meiosis I d) in either parent in somatic cell mitosis e) in the father in meiosis II

a) in the mother in meiosis II

failure to separate for homologous chromosomes or sister chromatids is referred to as ____ a) nondisjunction b) Robertsonian translocation c) pseudodominance d) gene dosage effect

a) nondisjunction

Additional copies of a gene ___ cause cellular problems. a) sometimes b) never c) always

a) sometimes

which statement about chromosome translocation is correct? a) translocation can affect gene expression by moving a gene under the control of a different promoter b) translocation and crossing over refer to the same phenomenon c) translocations do not affect chromosome number d) translocations only take place within a chromosome

a) translocation can affect gene expression by moving a gene under the control of a different promoter

what is the correct definition of polyploidy? a) the number of chromosome sets that make up a complete genome b) a chromosomal complement with at least three complete sets of homologous chromosomes c) the addition or loss of less than a full set of chromosomes or chromosome pairs d) a complete chromosome set or an exact multiple of the haploid chromosome set

b) a chromosomal complement with at least three complete sets of homologous chromosomes

during meiosis, errors can occur during chromosome replication. which term describes the addition of genetic material to a chromosome through extra replication? a) translocation b) duplication c) dicentric mutation d) nondisjunction

b) duplication

during meiosis, errors can be made during chromosome replication. Which term describes a mutation where a chromosome breaks, and its genetic material is reinserted in a different orientation? a) frameshift b) inversion c) duplication d) dicentric chromosome

b) inversion

Many errors can occur during meiosis. Which term describes the process of sister chromatids not separating at the centromere during cell division? a) desegregation b) nondisjunction c) aneuploidy d) cytokinesis

b) nondisjunction

during meiosis, errors occur during chromosome replication. Which term describes the rearranging of genetic material between nonhomologous chromosomes of genetic material? a) inversion b) translocation c) frameshift d) crossing over

b) translocation

which statement about Down syndrome is true? a) down syndrome never runs in the family, as it is based on a random aneuploidy event b) trisomy of chromosome 21 is well tolerated enough to give rise to a fully-developed individual c) the probability of a child having Down syndrome does not correlate with maternal age d) the primary cause for Down syndrome is the Robertsonian translocation

b) trisomy of chromosome 21 is well tolerated enough to give rise to a fully-developed individual

which statement about chromosome inversions is correct? a) chromosome inversions do not affect gene expression b) chromosome inversion can reduce the number of chromosomes in a cell c) chromosome inversions flip a segment of a chromosome 180 degrees d) chromosome inversions lead to an increase in crossovers

c) chromosome inversions flip a segment of a chromosome 180 degrees

The spread of a complete metaphase chromosome set presented for diagnostic purposes is called a ______. a) polyploidy b) genome c) karyotype d) translocation

c) karyotype

Of all cases of primary Down syndrome, 92% is caused by _______. a) nullisomy b) monosomy c) trisomy d) tetrasomy

c) trisomy

what is the correct definition of euploidy? a) the number of chromosome sets that make up a complete genome b) a chromosomal complement with at least three complete sets of homologous chromosomes c) the addition or loss of less than a full set of chromosomes or chromosome pairs d) a complete chromosome set or an exact multiple of the haploid chromosome set

d) a complete chromosome set or an exact multiple of the haploid chromosome set

a man has a large inversion on one of his chromosomes. how might this impact his offspring? a) no impact because all genetic information is retained b) minor genetic abnormalities due to minimal deficiency in genetic material c) fewer autosomes because normal synapsis during meiosis does not occur d) miscarriage or stillbirth caused by defective chromatids

d) miscarriage or stillbirth caused by defective chromatids

which statement about polyploidy is not true? a) polyploidy is a major mechanism by which new plant species have evolved b) polyploidy results from failure to separate a whole set of chromosomes during cell division c) polyploidy often results in larger cell size d) polyploidy is possible only between the members of the same species e) polyploidy is found in many of the food crop plants we enjoy, such as bananas and strawberries

d) polyploidy is possible only between the members of the same species

what is the correct definition of aneuploidy? a) a complete chromosome set or an exact multiple of the haploid chromosome set b) the number of chromosome sets that make up a complete genome c) a chromosomal complement with at least three complete sets of homologous chromosomes d) the addition or loss of less than a full set of chromosomes or chromosome pairs

d) the addition or loss of less than a full set of chromosomes or chromosome pairs

what type of chromosomal mutation is this? wild-type: AB*CDEFG mutated: AB*CDE

deletion of FG

what type of chromosomal mutation is this? wild-type: AB*CDEFG mutated: AB*DEFCDEFG

displaced duplication of DEF

what type of translocation is this? AB*CDEFG RS*TUVWX translocation 1 AB*CD RS*TUVWXEFG

nonreciprocal translocation of EFG

what type of translocation is this? AB*CDEFG RS*TUVWX translocation 1 AUVB*CDEFG RS*TWX

nonreciprocal translocation of UV

what type of chromosomal mutation is this? wild-type: AB*CDEFG mutated: AB*CGFED

paracentric inversion that includes DEFG

what type of chromosomal mutation is this? wild-type: AB*CDEFG mutated: AEDC*BFG

pericentric inversion of BCDE

what type of translocation is this? AB*CDEFG RS*TUVWX translocation 1 AB*TUVFG RS*CDEWX

reciprocal translocation of CDE and TUV

what type of translocation is this? AB*CDEFG RS*TUVWX translocation 1 AB*CWG RS*TUVDEFX

reciprocal translocation of DEF and W

what type of chromosomal mutation is this? wild-type: AB*CDEFG mutated: AB*CDEFDEFG

tandem duplication of DEF

match the definitions to the appropriate terms that describe the number of chromosomes terms: triploid trisomic n = 3 definitions: a genome composed of three unique chromosomes one extra copy of a specific chromosome three homologues of each chromosome

triploid: three homologues of each chromosome trisomic: one extra copy of a specific chromosome n = 3: a genome composed of three unique chromosomes