Chapters 23, 24, & 25 Conceptual Questions

Assuming complete penetrance, which type of inheritance pattern is consistent with the pedigree shown here? a. Autosomal recessive b. Autosomal dominant c. X-linked recessive d. X-linked dominant

a. Autosomal recessive

The identification of a stop codon for a particular gene is an example of a. sequence recognition. b. pattern recognition. c. both a and b. d. none of the above.

a. sequence recognition.

A gene knockout is a gene a. whose function has been inactivated. b. that has been transferred to a different species. c. that has been moved to a new location in the genome. d. that has been eliminated from a species during evolution.

a. whose function has been inactivated.

Which of the following is not a common explanation for a dominant disorder? a. Haploinsufficiency b. A change in chromosome number c. A gain-of-function mutation d. A dominant-negative mutation

b. A change in chromosome number

Which of the following would not be consistent with the idea that a disorder has a genetic component? a. The disorder is more likely to occur among an affected person's relatives than in the general population. b. The disorder can spread to individuals sharing similar environments. c. The disorder tends to develop at a characteristic age. d. A correlation is observed between the disorder and a mutant gene.

b. The disorder can spread to individuals sharing similar environments.

A mutant gene that promotes cancer when it is overexpressed is called a. a tumor-suppressor gene. b. an oncogene. c. both a and b. d. neither a nor b.

b. an oncogene.

Locus heterogeneity means that a genetic disorder a. has a heterogeneous phenotype. b. is caused by mutations in two or more different genes. c. involves a structural change in multiple chromosomes. d. is inherited from both parents.

b. is caused by mutations in two or more different genes.

The purpose of a ChIP-chip assay is to determine a. the expression levels of particular genes in a genome. b. the sites in a genome where a particular protein binds. c. the amount of a specific protein that is made in a given cell type. d. any of the above.

b. the sites in a genome where a particular protein binds.

For the method of RNA sequencing (RNA-Seq), which of the following is the correct order of steps? a. Isolate RNAs, synthesize cDNAs, fragment RNAs, sequence cDNAs, align cDNA sequences b. Synthesize cDNAs, sequence cDNAs, isolate RNAs, fragment RNAs, align cDNA sequences c. Isolate RNAs, fragment RNAs, synthesize cDNAs, sequence cDNAs, align cDNA sequences d. Synthesize cDNAs, isolate RNAs, fragment RNAs, sequence cDNAs, align cDNA sequences

c. Isolate RNAs, fragment RNAs, synthesize cDNAs, sequence cDNAs, align cDNA sequences

The BLAST program begins with a particular genetic sequence and a. translates it into an amino acid sequence. b. determines if it contains one or more genes. c. identifies homologs within a database. d. does all of the above.

c. identifies homologs within a database.

A DNA microarray is a slide that is dotted with a. mRNAs from a sample of cells. b. fluorescently labeled cDNAs. c. known sequences of DNA. d. known cellular proteins.

c. known sequences of DNA.

Tumor-suppressor genes promote cancer when a. they are overexpressed. b. they are expressed in the wrong cell type. c. their function is inactivated. d. they are expressed at the wrong stage of development.

c. their function is inactivated.

Which of the following is a type of genetic change that could produce an oncogene? a. Missense mutation b. Gene amplification c. Chromosomal translocation d. All of the above can produce an oncogene.

d. All of the above can produce an oncogene.

Which of the following types of epigenetic changes may promote cancer? a. DNA methylation b. Covalent modification of histones c. Chromatin remodeling d. All of the above may promote cancer.

d. All of the above may promote cancer.

Normal (nonmutant) tumor-suppressor genes often function a. as negative regulators of cell division. b. in the maintenance of genome integrity. c. in the stimulation of cell division. d. as both a and b.

d. as both a and b.

Homologous genes a. are derived from the same ancestral gene. b. are likely to carry out the same or similar functions. c. have similar DNA sequences. d. exhibit all of the above features.

d. exhibit all of the above features.

Personalized medicine may be used a. to characterize types of tumors. b. to predict the outcome of certain types of cancers. c. to determine the proper dosage of drugs. d. in all of the above.

d. in all of the above.

Most forms of cancer involve a. the activation of a single oncogene. b. the inactivation of a single tumor-suppressor gene. c. the activation of multiple oncogenes. d. the activation of multiple oncogenes and the inactivation of multiple tumor-suppressor genes.

d. the activation of multiple oncogenes and the inactivation of multiple tumor-suppressor genes.

The underlying cause(s) of epigenetic changes associated with cancer may be a. mutations in genes that encode chromatin-modifying proteins. b. environmental agents that alter the function of chromatin-modifying proteins. c. mutations in genes that encode proteins that directly accelerate cell growth. d. all of the above. e. both a and b.

e. both a and b.