Exam 17: Genomics: Genetics From a Whole-Genome Perspective

The accompanying hypothetical pedigree is for a family where some members have symptoms of Leigh syndrome, which is caused by an mtDNA mutation that reduces ATPase activity. Which of the following in the youngest generation might transmit the condition in the future?

Contrast the mechanism that gives rise to tortoise- shell cats (a mosaic coat color) with the mechanism that gives rise to variegated plants.?

The human genome contains DNA that is similar to mtDNA. Some of this DNA shows significant levels of nucleotide divergence from human mtDNA, while other nuclear DNA shows very high levels of nucleotide identity with mtDNA. Which of the following hypotheses best explains these data?

All of the following are evidence in support of the endosymbiotic origin of mitochondria, except?

Transcriptional regulation of mitochondrial genes closely resembles regulation of _ __________ operons.

Mitochondrial mutations in mammals are passed to the offspring by the ___________parent.

In 1718, the tsar of Russia, his wife the tsarina, and their five children were presumably assassinated and buried in an unmarked grave. Later, several women came forward and claimed that they were in fact Anastasia, one of the daughters whose bones had not been found. More recently, forensic scientists have extracted DNA, including mtDNA, from the skeletal remains. Which of the following samples of mtDNA had to be analyzed to discern which, if any, of the claimants was Anastasia?

What name is given to the alteration of an RNA sequence after transcription?

Among the discoveries that Correns and Bauer (1908) made in plants was that, sometimes, reciprocal crosses resulted in what pattern of inheritance?

Chloroplast mRNAs are not 5'- capped or polyadenylated, making them more like RNAs of domain _______.

What makes it possible for human mitochondria, which have only 22 sequences that code for tRNA, to translate mitochondrial polypeptides that require 32 tRNAs?

Giardia is eukaryotic yet is long thought to lack a mitochondira. Recently, researchers have found that each Giardia cell contains double membrane- bound organelles similar to a mitochondria called mitosomes that lack mtDNA. What is the best explanation for mitosomes?

In the 1950s, mitochondrial genomes were discovered by differential staining for________ .

Three of the four modes of inheritance of organelle genes are • maternal inheritance as in mammals, • paternal inheritance as in gymnosperms, and • selective degradation of one source during mating. What is the fourth?

Chlamydomonas, a unicellular green algae, is sensitive to an antibiotic, erythromycin. If mt- mating- type alga that is sensitive is mated with an mt+ cell that is resistant, and if the mt+ strain donates chloroplasts, what results do you expect and why?

There is a hypothetical gene in mice that produces a substance that induces twitchiness in hind leg muscles. A female mouse of a true- breeding twitchy strain is mated with a male of a true- breeding non- twitchy strain. All progeny are twitchy. Twitchiness may simply be a dominant trait caused by a nuclear allele, or it could be due to mtDNA. Which of these procedures would you use to provide evidence for your hypothesis that twitchiness is due to mtDNA?

Random segregation of organelles during cell division in a multicellular species is likely to result in an increased rate of which of the following?

In a cross between a petite yeast mutant and a wild- type strain, results showed half petite and half wild- type progeny. Which of these statements must be true of this petite mutation?

What is the argument that, although human mitochondria all descend from a single ancestral population, this may not be true for nuclear genomes?

Organisms have been created by nuclear transfer cloning, in which a diploid nucleus from a somatic cell of an adult animal is injected into an enucleated egg cell to create an embryo. Among the many species thus cloned, there has been a prevalence of mitochondrial defects. Which of the following is the most likely explanation?