BioSc 231 General Genetics Exam 4 Name Multiple Choice 2 points each Turner syndrome in humans is caused by which chromosomal conditions A 47 XXY B 47 21 C 45 X D 47 XYY E triploidy Clusters of highly repetitive DNA located near the centromeres and telomeres are called A Nucleosomes B Euchromatin C Chromatids D Heterochromatin E 30 nm chromatin Which histone protein is present as a monomer within the nucleosome and is not a part of the core particle A H1 B H2A C H2B D H3 E H4 E coli genomic DNA differs from a eukaryotic chromosome in that E coli DNA A Has a single centromere B Has telomeres C Is circular D Does not undergo supercoiling The genes coding for histones are repeated several times throughout the eukaryotic genome These genes would be described as A Highly repetitive DNA B Unique sequences C Heterochromatin D Transposons E Middle repetitive DNA A chromosome with its centromere in the middle is a A Submetacentric chromosome B Metacentric chromosome C Acrocentric chromosome D Telocentric chromosome Mosaicism is due to A X inactivation B chromosome duplication C chromosome deletion D somatic mutations E gametic mutations 47 XXY is a condition known as A Trisomy X syndrome B Klinefelter syndrome C Turner syndrome D Double Y syndrome E Fragile X syndrome A wild type chromosome can be represented as ABC DEFGH and from this a chromosomal aberration arises that can be represented AED CBFGH This is known as centromere A Deletion B Pericentric inversion C Translocation D Paracentric inversion E Duplication A female Drosophila supposedly heterozygous for two recessive mutations cn and lz that are on the same arm of the X chromosome cn lz surprisingly expresses both these genes The male progeny of the female will be A all wild type B all cn lz C 1 2 cn lz and 1 2 wild type D cn E lz When an organism gains or loses one or more chromosomes but not a complete haploid set the conditions is known as A polyploidy B euploidy C aneuploidy D triploidy It was once thought that the karyotype was related to criminal disposition because it led to aggressive behavior due to excessive maleness A XO B XY C XXY D XYY A set of Drosophila deletions in chromosome 2 was assembled as follows the lines indicate the region that has been deleted Regions 1 a b c d e f 2 3 4 5 6 7 A geneticist clones a gene from chromosome2 and wants to use the deletions to identify where the gene is located on chromosome 2 They use a radioactive DNA fragment containing their gene of interest and try to hybridize the DNA fragment to the chromosomal DNA from each mutant The radioactive DNA fragment only bound to chromosomal DNA from mutants a and f The gene must be in the region between A 1 and 2 B 2 and 3 C 3 and 4 D 4 and 5 E 5 and 6 Pollen from one species germinates on the stigma of another related species and sexually fertilizes the ovule Most of the resulting plants are sterile but some of the resulting offspring undergo chromosome duplication resulting in fertile plants The fertile offspring are known as A hexaploid B autopolyploid C monoploid D diploid E allopolyploid In a mammal how many inactivated X chromosomes Barr bodies would be present in cells of individuals who were XXX A 0 B 1 C 2 D 3 E 4 When an allotetraploid is backcrossed to one of its progenitor species a sterile progeny is produced The genomic composition of this sterile individual can be best represented by where n1 and n2 represent the haploid genomes of each progenitor species A n1 n2 B 2n1 2n2 C 2n1 D 2n2 E 2n1 n2 Euploidy is A a chromosome number that is not an exact multiple of the haploid number B an example of aneuploidy C a chromosome number that is an exact multiple of the haploid number D the addition of an extra copy of a particular chromosome E the absence of a particular copy of a chromosome The basic diploid chromosome number in pumpkins is 16 A new species of pumpkin is found that has four complete sets of the chromosomes found in the 16 chromosome species This species is said to be A haploid B diploid C triploid D tetraploid E pentaploid Consider a species with a diploid 2n number of 14 chromosomes How many chromosomes would be found in a trisomic body cell A 13 B 14 C 15 D 21 E 28 Consider a species with a diploid 2n number of 40 chromosomes How many chromosomes would be found in a monoploid body cell A 10 B 20 C 41 D 39 E 40 How many different trisomics could be formed in a plant with a diploid number of 10 A 5 B 10 C 11 D 9 E 20 When an organism gains or loses a complete monoploid set of chromosomes the conditions is known as A polyploidy B euploidy C aneuploidy D triploidy E trisomy Short Answer 2 points each What happens when monoploid plant cells are treated with colchicine What is the name of the process of staining the chromosomes from a metaphase cell and arranging the chromosomes according to their length and centromere placement Why is polysomy more harmful than polyploidy How many Barr bodies would you expect to see in the cells of a person who has the condition 47 XXY Why are centromeres and telomeres required for chromosomes to be genetically stable Why is topoisomerase necessary during replication of the E coli chromosome Explain why there is usually a single gene in the genome for a particular protein i e an enzyme involved in a biosynthetic pathway whereas genes for ribosomal RNA rRNA and tRNA are repeated many times Recessive alleles a b c d e f and g are closely linked but their order is unknown A set of 7 deletions are used to determine the gene order as revealed by the genes uncovered by each deletion The genes uncovered by each mutation are as follows 1 a and b 2 a b and e 3 b and c 4 c 5 d and f 6 d f and g 7 e f and g What is the order of the genes Bonus 4 points Describe the structure of eukaryotic chromatin from the basic building blocks to the compact structure found in metaphase cells Include all proteins involved in forming the structure and all intermediate structures Please circle two topics that you would most like to cover over the last section of the course Bacterial Genetics Gene Regulation Gene Expression Development The Cell Cycle Population Genetics and Evolution