Genetics Final Review- Tests

Assuming a typical monohybrid cross in which one allele is completely dominant to the other, what genotypic ratio is expected if the F1s are crossed? A. 1:2:1 B. 2:1 C. 3:1 D. 1:1

A. 1:2:1

If a Drosophila that has a cinnabar eye mutation on one homolog of chromosome 1 and a deletion in a different interval of the other homolog, what would be the phenotypic outcome and why? A. It would hane cinnabar eyes due to the recessive mutant expressing its phenotype. B. It would be wild type due to the dominant allele still expressing itself. C. It would have a mosaic of wild type and cinnabar due to presence of the recessive allele and the deletion. D. It would have cinnabar eye due to the homozygosity of the recessive allele.

A. It would hane cinnabar eyes due to the recessive mutant expressing its phenotype

Mutations in the lacI and lacO genes of the lac regulatory system in E. coli often lead to full transcription of the three structural genes, even when no lactose is available to the organism. Such mutations would be called ________. A. constitutive B. activated C. attentuated D. induced

A. constitutive

If a species has a haploid number of 52, what term would we use to describe an individual with 26 chromosomes? A. eusomic B. haploid C. trisomic D. monosomic

A. eusomic

When X rays penetrate cells, electrons are ejected from atoms of molecules. Stable molecules can be transformed into which two types of hazardous materials? A. free radicals and reactive ions B. heterocyclic amines and acetaldehyde C. 6-ethylguanine and 5-bromouracil D. thymine dimes are superoxides

A. free radicals and reactive ions

Fluorescence in situhybridization (FISH) would most likely be used to study ________. A. tissue specific expression patterns B. the phenotypic effects of a non-functional mutant gene C. DNA sequence variation among individuals D. gene specific mutation rates

A. tissue specific expression patterns

The genes for the recessive traits of mahogany eyes and ebony body are approximately 25 map units apart on chromosome III in Drosophila. Assume that a mahogany-eyed ebony-bodied female was mated to a wild-type male and that the resulting F1 phenotypically wild-type females were then mated to mahogany, ebony males. Of 1000 offspring, what would be the expected phenotypes, and in what numbers would they be expected? A. wild-type = 375; mahogany-ebony = 375; mahogany = 125; ebony = 125 B. wild-type = 250; mahogany-ebony = 250; mahogany = 250; ebony = 250 C. mahogany = 375; ebony = 375; wild-type = 125; mahogany-ebony = 125 D. mahogany = 400; ebony = 400; wild-type = 100; mahogany-ebony = 100

A. wild-type = 375; mahogany-ebony = 375; mahogany = 125; ebony = 125

If 15 percent of the nitrogenous bases in a sample of DNA from a particular organism is thymine, what percentage should be adenine? A. 30 percent B. 15 percent C. 70 percent D. 35 percent

B. 15 percent

Assume that a circular plasmid is 3900 base pairs in length and has restriction sites at the following locations: 600, 1700, 1900, 2600. Give the expected sizes of the restriction fragments following complete digestion. A. 800. 1900, 1200 B. 200, 700, 1100, 1900 C. 300, 1100, 1200, 1300 D. 400, 1200, 1200,1300

B. 200, 700, 1100, 1900

Which protein directly holds the chromatid arms together prior to anaphase of mitosis? A. separase B. cohesin C. histone D. shugoshin

B. cohesin

Which of the following is the side of the replication fork where synthesis is continuous? A. origin of replication B. leading strand C. lagging strand D. template strand

B. leading strand

What is the function of aminoacyl tRNA synthetase? A. It adds an anticodon to tRNA B. It folds tRNA into a clover leaf structure C. It binds an amino acid to its tRNA D. It binds to the mRNA cap during initiation

C. It binds an amino acid to its tRNA

Which one of the following is found in eukaryotic mRNAs upstream of the AUG and increases initiation efficiency? A. shine-delgarno sequence B. initiation sequence C. Kozak sequence D. TATA box

C. Kozak sequence

Which of the following is not a true statement regarding retroviruses? A. RNA serves as genetic material. B. The human immunodeficiency virus (HIV) is an example of a retrovirus. C. RNA is converted to DNA by DNA polymerase. D. DNA generated from retroviruses can potentially integrate into the host's genome.

C. RNA is converted to DNA by DNA polymerase.

Which eukaryotic enzyme is responsible for replication of the ends of chromosomes? A. pol a B. helicase C. telomerase D. topoisomerase

C. telomerase

The pre-initiation complex (PIC) contains several proteins. What would the direct consequence be if PIC failed to form? A. replication would not be initiated B. translation would not be initiated C. transcription would not be initiated D. mRNA splicing would not be initiated

C. transcription would not be initiated

When two genes do not fail to assort independently, the term normally applied is ________. A. discontinuous inheritance B. tetrad analysis C. unlinked D. linkage

C. unlinked

Which E-value represents the highest probability of a BLAST result not being chance? A. 0.1 B. 0.01 C. 1 × 10-3 D. 1 × 10-4

D. 1 × 10-4

A recessive allele in dogs causes white spots. If two solid-colored dogs are mated and produce a spotted offspring, what is the percentage chance their next two puppies would be spotted? A. 1/2=50% B. 1/4=25% C. 3/4=75% D. 1/16=6.25%

D. 1/16=6.25%

Which of the following is true about histone acetyltransferase (HAT)? A. HATs will remove acetyl groups from histone proteins. B. HATs will add acetyl groups to DNA. C. HATs will make the chromatin more compacted and less available to transcription regulatory proteins. D. HATs are usually linked to increasing gene expression.

D. HATs are usually linked to increasing gene expression.

Which of the following middle repetitive sequences are not categorized as tandem repeats? A. STRs B. VNTRs C. rRNA genes D. SINEs

D. SINEs

The condition that exists when an organism has three sets of chromosomes per nucleus is called___________, while the presence of two sets of chromosomes, plus one chromosome is called___________. A. polyploidy, trisomy B. trisomy, triploidy C. trisomy, euploidy D. triploidy, trisomy

D. triploidy, trisomy

The investigative approach of genetics attributed to Gregor Mendel is ________. A. population genetics B. cytogenetics C. transmission genetics D. molecular genetics

c. transmission genetics