Question: Inversions are most likely to affect an organism’s phenotype
Answer Options:
• A) If one or both of the inversion’s breakpoints lies within the transcribed region of a gene.
• B) If the inversion’s breakpoints are on either side of a gene and its regulatory regions and the entire gene is reversed in the genome.
• C) If the inversion is pericentric.
• D) If the inversion is paracentric.
• E) If the inversion is small.
Answer: A) If one or both of the inversion’s breakpoints lies within the transcribed region of a gene.
Question: What mechanism used for mobilization of transposable elements can lead to deletions in genomes?
Answer Options:
• A) Transposase sometimes deletes genomic DNA while removing DNA transposons from the genome.
• B) Alignment of two transposable elements is required for mobilization and misalignment can result in deletions.
• C) RNA polymerase transcribes transposable elements; when it makes mistakes, DNA nucleotides are sometimes deleted.
• D) Piwi RNAs inhibit movement of transposons by deleting DNA that includes and surrounds the inverted repeats.
Answer: A) Transposase sometimes deletes genomic DNA while removing DNA transposons from the genome.
Question: Duplications are most likely to have phenotypic consequences if
Answer Options:
• A) A gene within the duplication is haploinsufficient.
• B) An additional dose of a gene within the duplication does not affect tissue physiology.
• C) The expression of a gene near one duplication breakpoint is altered.
• D) An allele of a gene within the duplication is amorphic.
Answer: C) The expression of a gene near one duplication breakpoint is altered. I will continue completing all remaining questions.
Question: Which of the following features is shared by mobile transposable elements in the human genome?
Answer Options:
• A) RNA intermediates
• B) Functional transposase genes
• C) Mutant LTRs
• D) Mutant pol genes
Answer: A) RNA intermediates
Question: Which is not an example of aneuploidy?
Answer Options:
• A) Monosomy
• B) Tetraploidy
• C) Trisomy
• D) Nullisomy
Answer: B) Tetraploidy
Question: What is a reason that aneuploidy in sex chromosomes is generally better tolerated than aneuploidy in autosomal chromosomes in humans?
Answer Options:
• A) In somatic cells, most of the genes on only one X chromosome are transcriptionally active.
• B) Autosomal aneuploidy leads to heart defects and death in utero.
• C) Y chromosome duplication results in only minor changes in testosterone levels.
• D) Sex chromosome aneuploids may occur as the result of fertilization, but extra sex chromosomes are removed from the developing embryo during subsequent mitosis.
• E) Any change in autosome number results in increased susceptibility to infection.
Answer: A) In somatic cells, most of the genes on only one X chromosome are transcriptionally active.
Question: Which sex chromosome aneuploidy is not usually seen in live births?
Answer Options:
• A) XO
• B) XXY
• C) YO
• D) XXX
Answer: C) YO
Question: Turner syndrome (XO) is a sex chromosome aneuploidy. Of the effects listed below, which one is not usually seen in this syndrome?
Answer Options:
• A) Unusually short stature
• B) Infertility
• C) Skeletal abnormalities
• D) Unusually long limbs
Answer: D) Unusually long limbs
Question: In Drosophila, a gynandromorph, which is composed of equal parts of male and female tissue, results from
Answer Options:
• A) An XX female losing one X chromosome during the first mitotic division after fertilization.
• B) An egg carrying an X chromosome fertilized by a Y-carrying sperm.
• C) A normal egg fertilized by both an X-carrying sperm and a Y-carrying sperm.
• D) The fusion of a female embryo with a male embryo.
Answer: A) An XX female losing one X chromosome during the first mitotic division after fertilization.
Question: Which is not an example of euploidy?
Answer Options:
• A) Seedless watermelons have three copies of each chromosome.
• B) A normal human has two copies of each chromosome.
• C) A human with Down syndrome has three copies of chromosome 21.
• D) Commercially grown strawberry plants have eight copies of each chromosome.
Answer: C) A human with Down syndrome has three copies of chromosome 21.
Question: Triploid organisms usually result from
Answer Options:
• A) The union of monoploid and diploid gametes.
• B) Nondisjunction during mitosis.
• C) Propagation of fused cell lines.
• D) A fertilization event that involves three monoploid gametes.
• E) Normal fertilization of gametes produced by triploid parents.
Answer: A) The union of monoploid and diploid gametes.
Question: During mitosis, if all of the chromosomes in a diploid cell fail to separate and instead segregate into one daughter cell, the result will be what?
Answer Options:
• A) One monoploid daughter cell and one triploid daughter cell
• B) One 2x−1 daughter cell and one 2x+1 daughter cell
• C) Two 2x daughter cells
• D) Only one tetraploid daughter cell
Answer: D) Only one tetraploid daughter cell