Genetics Exam 3 Moodle Quizzes

Consider a species with a diploid number of 12. How many chromosomes would be found in a trisomic body cell?

13

In what year was the first draft of the human genome published?

2001

What is the maximum number of alleles a SNP can have?

4 A single nucleotide can have four different bases: A, G, C, or T

A particular SNP locus can be A, C or T. How many different genotypic combinations can be expected to be found in the population?

6

For the SNP described in the previous question, the allele frequencies for A, C and T are 0.03, 0.68 and 0.29, respectively. In a population of 10,000, the number of people expected to only have the 'A' allele would be:

9 The chance of having BOTH alleles be "A" is 0.03 * 0.03 (then multiply by the population).

d. .AbhgfedCBa.

Below is an illustration of a paracentric inversion heterozygote during prophase I of meiosis. It shows 6 different potential crossover sites. If you have crossing over at ONLY positions 6 and 4, which of the following will NOT be seen? (Note: periods represent centromeres in the answers.) a. .ABCDEFghbA. b. JIHGfedcij c. .abhgfedcij d. .AbhgfedCBa. e. .aBCDEFGHIJ

c. 2; yes Correct

One particular microsatellite has four alleles in the population and is closely linked to an autosomal dominant form of early Alzheimer's disease. Which polymorphism is early Alzheimer's associated with in this family? Does the male indicated by the ? carry the allele for early Alzheimer's? a. 1; no b. 2; no c. 2; yes d. 3; yes e. 3; no

Why might you want to search a database for a protein motif? a. A specific motif may impart a specific function to the molecule. You could then identify groups of proteins that may have similar functions. b. Presence of a specific motif in several proteins indicates that they are likely to be all from the same species. c. Absence of a specific motif from one of a pair of otherwise similar proteins indicates that they are produced by alternative splicing of the same gene. d. Presence of a multiple copies of a motif in the same proteins indicates an important function.

a. A specific motif may impart a specific function to the molecule. You could then identify groups of proteins that may have similar functions.

After assigning you a given gene, your instructor tells you to go to the NCBI Human Genome page. What does she probably want you to do? a. Determine what genes are around 'your' protein's gene on its chromosome b. Identify a DNA sequence and see if it came from a human. c. Look up papers about diseases caused by abnormalities in a certain protein d. Look at colorful, rotating, 3-D pictures of the tertiary structure of a protein.

a. Determine what genes are around 'your' protein's gene on its chromosome

If two distantly related organisms have regions of conserved synteny, what does this mean? a. The genes examined in the two species are present in the same order as in their most recent common ancestor. b. The genes examined in the two species are identical in sequence to each other. c. The genes examined in the two species are on different chromosomes, but in their last common ancestor, the genes were on the same chromosome. d. The genes examined in the two species have each duplicated, creating family members with different functions (like alpha and beta globin genes)

a. The genes examined in the two species are present in the same order as in their most recent common ancestor.

In eukaryotes, individual protein domains are generally encoded by single ____ a. exons b. introns c. genes d. chromosomal bands e. nucleotide pairs

a. exons

All genes with sufficient sequence similarity to have evolved from a common ancestor anywhere in evolutionary time are ________, while ________ are genes in different species that arose from the same gene in a very recent ancestor of the two species and ________ arise by duplication events within the same species. a. homologs; orthologs; paralogs b. homologs; paralogs; orthologs c. orthologs; homologs; paralogs d. orthologs; paralogs; homologs e. paralogs; orthologs; homologs

a. homologs; orthologs; paralogs

In microsatellites, _____________ base sequences are tandemly repeated about _______ times a. one to three; 15-100 b. 20-100; 10-1000s c. one to three; 10-1000s d. 20-100; 15-100

a. one to three; 15-100

A "metagenome" is ... a. the complete genetic complement of an environmental sample b. the complete genomes of all organisms of a species c. the complete genetic complement of an organism d. the complete genomic content of a metazoan e. the study of bacterial contributions to metazoan symbiotes

a. the complete genetic complement of an environmental sample

What do deletions, inversions, and translocations have in common? a. They all contain normal amounts of genetic material in unusual arrangements. b. They all can be caused by DNA breakage and inaccurate repair. c. They all involve loss of genetic material. d. They all involve extra genetic material in a karyotype.

b. They all can be caused by DNA breakage and inaccurate repair.

Polyploidy refers to: a. an individual with an extra copy of a chromosome b. an individual with complete extra sets of chromosomes c. extra copies of a gene adjacent to each other on a chromosome d. a chromosome which has replicated but not divided

b. an individual with complete extra sets of chromosomes

Which structures in eucaryotic genes are thought to have facilitated the ability to duplicate a protein domain of a gene without damaging it in the recombination process? a. exons b. introns c. promoters d. heterochromatin e. regulatory regions

b. introns

In deletion mapping, mutations can be localized to a region of the gene because: a. the mutation fails to complement other mutations in the gene b. the mutation fails to complement a deletion of a known portion of the gene c. the deletion will always be visible in a karyotype d. the gene sequence can be determined

b. the mutation fails to complement a deletion of a known portion of the gene

The molecular basis of microarray analysis is based upon _____. a. base pair complementarity between microRNA and mRNA b. the half-life of mRNAs in the cell undergoing investigation c. hybridization between reverse-transcribed mRNAs and anchored single-stranded oligonucleotides representative of specific genes d. the relative fraction of total RNA that makes up the mRNA pool e. a short (usually 20 to 24-bp) double-stranded RNA (dsRNA) with phosphorylated 5' ends and hydroxylated 3' ends with two overhanging nucleotides that hybridizes to genes of interest when heated.

c. hybridization between reverse-transcribed mRNAs and anchored single-stranded oligonucleotides representative of specific genes

If the normal sequence of a chromosome is A B C D . E F G H, what type of chromosomal abnormality is shown here: A D . E F B C G H ? a. inversion b. transposon c. translocation d. duplication e. deletion

c. translocation

Huntington disease is caused by: a. a closely linked marker allele. b. ferwer than 34 CAG repeats. c. a large deletion. d. 42 or more CAG repeats. e. a recessive allele.

d. 42 or more CAG repeats.

In Barbara McClintock's famous experiments revealing the existence of transposable genes, she primarily used which of the following as her experimental organism: a. Drosophila melanogaster b. Ciona intestinalis c. Escherichia coli d. Zea mays e. Homo sapiens

d. Zea mays

Transposable element insertion into a gene may result in: a. a splicing defect b. frameshift mutations c. nonsense mutations d. all of these choices are possible

d. all of these choices are possible

Which of the following is the main source of variation in microsatellites? a. chemicals in water b. chemicals in the air c. ultraviolet radiation d. faulty DNA replication e. faulty protein folding

d. faulty DNA replication

A cell from a normally diploid organism is examined, and the chromosomal make-up is found to be 2N+2. We could describe that cell as... a. haploid b. trisomic c. diploid d. tetrasomic e. tetraploid

d. tetrasomic

The term 2n-1 would apply to a _______ condition? a. Trisomy b. Autopolyploidy c. Eusomy d. Haploidy e. Monosomy

e. Monosomy

Raphanobrassica was created from a cross between a cabbage and a radish, each of which has 18 chromosomes. Raphanobrassica has 36 chromosomes and is fertile. This is an example of a/an... a. monoploid b. triploid c. autopolyploid d. trisomy e. allopolyploid

e. allopolyploid